A new study from <a href="https://www.osu.edu/">Ohio State University</a> reveals what is going on inside of your <a href="https://www.earth.com/news/gut-brain-interactions-have-an-influence-on-diseases/">brain</a> when you get lost in a fictional fantasy. The experts discovered that the more immersed we become in the lives of our favorite characters of fiction, the more our brain activity reflects how much we identify with them.
&#8220;When they think about a favorite fictional character, it appears similar in one part of the brain as when they are thinking about themselves,&#8221; said study lead author Timothy Broom.
The research was focused on self-described fans of the HBO series &#8220;Game of Thrones.&#8221; The individuals were instructed to think about themselves, nine of their friends, and nine characters from the drama series. The participants also reported on which character they felt closest to and liked the most.
According to Broom, Game of Thrones was ideal for this study because it attracted a devoted fan base and the large cast presented a variety of characters that people could become attached to.
One of the key findings involved participants who scored highest on &#8220;trait identification.&#8221; These individuals agreed most strongly with statements like &#8220;I really get involved in the feelings of the characters in a novel.&#8221;
&#8220;People who are high in trait identification not only get absorbed into a story, they also are really absorbed into a particular character,&#8221; said Broom. &#8220;They report matching the thoughts of the character, they are thinking what the character is thinking, they are feeling what the character is feeling. They are inhabiting the role of that character.&#8221;
The researchers used an fMRI machine to measure activity in various parts of the brain through small changes in blood flow. As the participants&#8217; brains were scanned, they were evaluating themselves, their friends, and Game of Thrones characters. 
A part of the brain called the ventral medial prefrontal cortex (vMPFC) is known to show increased activity when people think about themselves and, to a lesser extent, when they think about close friends.
While in the fMRI, the individuals were shown a series of names &#8211; including themselves, friends, or characters &#8211; along with a trait, such as lonely, sad, trustworthy, or smart. The participants simply said &#8220;yes&#8221; or &#8220;no&#8221; to imply whether the trait fit the person.
As expected, the vMPFC was most active when people were evaluating themselves, less active when they evaluated friends, and least active when they evaluated characters from Game of Thrones.
However, among those who were high in trait identification, the vMPFC was more active when they thought about the fictional characters than it was for participants who identified less with the characters. This region of the brain was particularly active when the individuals evaluated the character they identified with the most.
Study co-author Dylan Wanger said the findings help explain how fiction can have such a big impact on some people.
&#8220;For some people, fiction is a chance to take on new identities, to see worlds though others&#8217; eyes and return from those experiences changed,&#8221; said Wagner.
&#8220;What previous studies have found is that when people experience stories as if they were one of the characters, a connection is made with that character, and the character becomes intwined with the self. In our study, we see evidence of that in their brains.&#8221;
The study is published in the journal <a href="https://academic.oup.com/scan">Social Cognitive and Affective Neuroscience</a>.
&#8211;&#8212;
By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

What happens in your brain while you're lost in fiction

Healthy,Food,,Plate,With,Greek,Salad,Of,Mediterranean,Diet,,Tomatoes

A new study shows that adults 65 and older who follow the Mediterranean diet live longer. Interestingly, adherence to the Mediterranean diet was assessed by analyzing biomarkers in plasma and urine, which is a unique approach.



Professor Cristina Andrés-Lacueva is head of the Research Group on Biomarkers and Nutritional &amp; Food Metabolomics of the Faculty of Pharmacy and Food Sciences of the <a href="https://www.ub.edu/web/portal/en/">University of Barcelona</a> (UB) and the CIBER on Fragility and Healthy Ageing (CIBERFES).



According to Professor Andrés-Lacueva, her team developed an index of dietary biomarkers based on <a href="https://www.earth.com/news/air-pollutants-confuse-pollinators-and-reduce-food-production/">food</a> groups that are part of the Mediterranean diet, and then assessed their association with mortality. Professor Andrés-Lacueva is also head of the research group in Ciber on Fragility and Healthy Aging (CIBERFES).



The research was carried out over 20 years, using data from 642 participants who were 65 years and older and resided in the Tuscany region of Italy.&nbsp;



The scientists looked at the following biomarkers: polyphenols and resveratrol metabolites (from grape consumption), plasma carotenoids, selenium, vitamin B12, fatty acids and the proportion of monounsaturated and saturated fatty acids.&nbsp;



Using a model and a food questionnaire, the scientists were able to ascertain how closely each participant followed a Mediterranean diet. During the course of the twenty-year study, 425 participants died - 139 from cardiovascular disease and 89 from cancer related causes.&nbsp;



When analyzed, the biomarkers associated with a Mediterranean diet were inversely related to all causes of death. This means that the health benefits of a Mediterranean diet can boost longevity.



Tomás Meroño, co-first signatory of the study, said the study confirms that adherence to the Mediterranean diet (assessed by a panel of dietary biomarkers) is inversely associated with the long-term mortality in older adults, which supports the use of these biomarkers in monitoring evaluations to study the health benefits associated with the Mediterranean diet.



"A healthy diet is considered one of the fundamental factors to achieve healthy aging," wrote the study authors. "Indeed, a growing body of epidemiological evidence shows that the Mediterranean diet (MD) may delay or prevent frailty, cognitive decline, and the onset of many chronic diseases in older subjects."&nbsp;



"Furthermore, several observational studies, including the European Prospective study into Cancer and Nutrition (EPIC)-elderly study, a cohort of 74,607 men and women aged ≥60 years, have shown inverse associations between a greater adherence to different MD scores (MDS), in both the Mediterranean and non-Mediterranean countries, and total mortality."



The study is published in the journal <a href="https://bmcmedicine.biomedcentral.com/">BCM Medicine</a>.



---By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Mediterranean diet can lead to longer life

A new study shows that adults 65 and older who...

The power of positive thinking came to the forefront in recent research conducted by scientists at <a href="https://www.osu.edu/">The Ohio State University</a>. The study revealed that people who were in a sad <a href="https://www.earth.com/news/dark-chocolate-triggers-mood-boosting-changes-in-the-gut/">mood</a> improved more quickly when they used a therapeutic method that they believed to be aligned with their strongest skill. These participants improved more quickly than people asked to use a skill that they believed to be a relative weakness.



“We found that it helps people to think they’re working with their strengths rather than with something they see as a weakness,” said study lead author&nbsp;<a href="https://scholar.google.com/citations?user=WD5esBUAAAAJ&amp;hl=en">Samuel Murphy</a>.



The unusual thing about this study was that the participants were randomly told what their strong skill was, regardless of whether this was true or not. What was important was not if the participants actually had their assigned skill in abundance, but if they believed they had it.



“Our results suggest that whether participants were good at the skill was not relevant. It was the belief that they were good at that skill that made it effective,” explained study co-author Professor&nbsp;<a href="https://psychology.osu.edu/people/strunk.20">Daniel Strunk</a>.



For the investigation, 616 undergraduate participants were introduced to two different therapy skills, one using a cognitive approach and the other using mindfulness. The participants were told that these therapy skills could be useful in their daily lives.&nbsp;



Cognitive skills were defined as identifying and re-evaluating negative thoughts and beliefs.&nbsp;Mindfulness skills were defined as awareness and acceptance of one’s thoughts and feelings without trying to change them.



Participants were then given a hypothetical situation in which they could use these skills – feeling hurt by not being invited to a social event by a friend – and directed to practice both skills and complete some questionnaires on how they used them. Following this exercise, the researchers told each participant which one, cognitive or mindfulness, was his or her stronger skill. In reality, however, the participants were simply assigned to each skill group randomly.



The participants then underwent a “sad mood induction,” during which they were told to imagine vividly that someone they cared about was dying, while at the same time they listened to the sad song “Russia under the Mongolian Yoke,” played at half speed to make it sound even sadder. They then had to use the therapy skills to help themselves recover from the sad mood and they completed five mood assessments in the minutes following the completion of the sad mood induction.



In one last requirement, half of those who were told that mindfulness was their stronger skill had to use cognitive skills (their weaker strategy) to recover from the sad mood, while the other half had to use mindfulness (their stronger strategy). Similarly, those participants who were told that a cognitive approach was their stronger skill had to use mindfulness when dealing with a sad mood, while the other half had to use cognitive strategies.



The results showed that all of the participants saw their sad mood gradually improve after the induction was over. Whether they were asked to use cognitive or mindfulness skills had no significant effect on mood recovery – but the framing of whether they were told it was their strongest or weakest skill did make a difference.



Participants who used the skill they had been told was their strongest - regardless of whether it was cognitive or mindfulness - saw a bigger improvement in mood than participants who worked with a skill they had been told was their weakest.



The study authors could not explain why framing the therapy skill as a strength resulted in a more rapid mood recovery.&nbsp;



“It may be that if there is this initial encouragement early on that they are really good at one particular strategy, that may inspire greater confidence and persistence in using this skill, which leads to better results,” said Murphy.



Or it may be the other way around: “People may be discouraged if they’re told a particular skill is their weakness and then not try as hard or be as confident that it will work,” Strunk said.



The researchers noted that the findings may be helpful to therapists who focus on building clients’ strengths. “It is very easy to let clients know that you’re building on their strengths, so if it enhances the benefit, that will be important to try,” said Murphy.



This approach is particularly relevant currently as psychotherapists focus more on encouraging clients to use their skills to help deal with and solve their own problems, rather than being dependent on the therapist to “fix” the problems. This represents a paradigm shift and psychotherapists are still learning how to maximize their success in this approach.



“How therapists frame the treatment for a client may play an important role in how well it works. Telling clients that you’re going to be working on their strengths may further enhance the effectiveness of their treatment,” Strunk said.



“We only studied mindfulness and cognitive skills here, but there are a variety of approaches to improving mental health,” he said. “The ones that you think would work best for you probably will indeed work best.”



The study is published in the <a href="https://onlinelibrary.wiley.com/journal/10974679">Journal of Clinical Psychology</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Focusing on your strongest skills can improve your outlook

The power of positive thinking came to the forefront in...

A new study has revealed that the equivalent of 61 million olympic-sized pools of fresh <a href="https://www.earth.com/news/the-sun-may-be-the-original-source-of-earths-water/">water</a> were released into the seas near South Georgia when "mega" iceberg A68A melted over three months from 2020 to 2021.&nbsp;



In July 2017, the iceberg broke off the Larsen-C Ice Shelf on the Antarctic Peninsula and began an incredible 4,000 kilometer journey across the Southern Ocean over threw and a half years. The British Antarctic Survey (BAS) monitored the berg’s location, and how it’s area and thickness changed over time via satellite technology.&nbsp;



“A68 was an absolutely fascinating iceberg to track all the way from its creation to its end," said Laura Gerrish, GIS and mapping specialist at BAS. "Frequent measurements allowed us to follow every move and break-up of the berg as it moved slowly northwards through iceberg alley and into the Scotia Sea where it then gained speed and approached the island of South Georgia very closely.“



The amount of water released from the melting iceberg could have far reaching consequences. It’s unknown what impact the release of 152 billion tonnes of fresh water near an island like South Georgia will be.&nbsp;



“This is a huge amount of melt water, and the next thing we want to learn is whether it had a positive or negative impact on the ecosystem around South Georgia," said study lead author Anne Braakmann-Folgmann, a researcher at CPOM and PhD candidate in the School of Earth and Environment at the <a href="https://www.leeds.ac.uk/">University of Leeds</a>.



Because the technological ability to track icebergs via satellite is relatively new, scientists hope to harness this ability to learn even more. A68A took a common route while crossing the Drake Passage, so it could tell us a lot about icebergs and their impact on polar oceans.&nbsp;



“Our ability to study every move of the iceberg in such detail is thanks to advances in satellite techniques and the use of a variety of measurements," said Tommaso Parrinello, CryoSat Mission Manager at the European Space Agency.



Imaging satellites record the location and shape of the iceberg and data from altimetry missions add a third dimension as they measure the height of surfaces underneath the satellites and can therefore observe how an iceberg melts. “



The study is published in the journal <a href="https://www.journals.elsevier.com/remote-sensing-of-environment">Remote Sensing of Environment</a>.



---



By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Mega iceberg released 152 billion tons of fresh water

A new study has revealed that the equivalent of 61...

In a recent study from <a href="https://www.ucr.edu/">UC Riverside</a> researchers investigated whether black-eyed peas had lost any of their ability to attract Bradyrhizobium (nitrogen-fixing bacteria from the soil) and establish them inside nodules in the roots. As black-eyed peas are an important crop in many parts of the world, this ability may have been lost during domestication or selective breeding over centuries.&nbsp;



All plants need nitrogen in order to form the proteins needed for growth. If there is not enough nitrogen present, plants will not grow successfully. Although the atmosphere contains around 80 percent nitrogen gas (N2), plants cannot use it in this form. Instead, it has to be “fixed” into the form of ammonia (NH3), nitrate (NO3-) or nitrite (NO2-). It is most often bacteria in the soil that fix nitrogen into these forms, thereby making essential nutrients available for absorption by plant roots.



Legumes, including crop plants such as peas, beans and lucerne, go a step further than this. They attract nitrogen-fixing bacteria by secreting enticing chemicals through their roots. Once bacteria have attached to the root hairs, the plant secretes different substances that the bacteria to enter root hair cells and travel into the main root. Once inside the root, the bacteria cause root cells to divide and form a tumor-like nodule which is where nitrogen-fixing activity can take place. &nbsp;



In the symbiotic relationship that ensues, the legume plants receive a useful, fixed form of nitrogen to use for growth, and the plants provide a supply of carbohydrates to the bacteria, along with a safe place to live.



“The ability of legumes to do this caused them immense success as the third biggest plant family on the planet,” said Joel Sachs, UCR professor of evolution and ecology.&nbsp;



Unfortunately, plant breeders often select intensely for above-ground characteristics of crop plants, such as their yield, disease resistance and protein content, when trying to improve the quality of the plants. They do not focus on the important ability of roots to attract bacteria and enter into a symbiotic relationship with them – something that is essential for the supply of nitrogen to the growing plants.



Study lead author Gabriel Ortiz wanted to find to find out whether modern farming practices had resulted in a loss of symbiotic ability in black-eyed pea plants. In many cases, plants heavily impacted by humans do not benefit as much from relationships with bacteria as their wild relatives do.&nbsp;



The researchers used genome-wide analyses, along with a greenhouse inoculation study, to investigate genomic diversity, heritability, and symbiosis trait variation among 20 different varieties of wild and early-domesticated black-eyed peas.&nbsp;



They found that, although there was evidence that the peas experienced modest decreases in genome diversity during early domestication, they had kept their natural ability to form beneficial symbiotic relationships with nitrogen-fixing bacteria. The experiments even showed that domesticated populations made more root nodules than wild varieties of black-eyed peas.&nbsp;



“In fact, some of the strains in the experiment appear to have gained more benefit from bacteria than their wild ancestors,” Sachs said.



The authors attribute this unexpected result to the fact that black-eyed pea landraces were developed in Africa where the low nutrient conditions would have favored plant genotypes that use symbiosis with nitrogen-fixing bacteria in an efficient manner. This implies that early breeders inadvertently selected for plants with excellent ability to attract and protect these symbiotic bacteria.&nbsp;



Modern breeders have largely neglected symbiosis traits when selectively breeding black-eyed peas, but future artificial selection for improved plant responses to nitrogen-fixing bacteria could increase plant performance and sustainability.



“We can use this information in the future to design better performing plants,” said Ortiz. He and his team focused on black-eyed peas because they are also drought tolerant, another important trait for Southern California growers.&nbsp;



Furthermore, farmers can use black-eyed pea crops to enrich their soil with nitrogen, rather than having to add inorganic fertilizer. When nitrogen fertilizer is applied it can end up being carried away with rain water and polluting rivers, lakes and oceans, or it can enter the atmosphere as a greenhouse gas.



“When the plant senses it is going to die, it releases the bacteria into the soil, replenishing it,” Ortiz explained. “Growers could alternate seasons of legumes with other crops, leaving the soil full of nitrogen-fixing bacteria that reduce the need for fertilizer.”



“To make agriculture more sustainable, one of the things we need to do is focus on the plant’s ability to get services from microbes already in the soil, rather than trying to get those services by dumping chemicals,” Sachs said.&nbsp;



The study is <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/evo.14424">published</a> in the journal&nbsp;<a href="https://onlinelibrary.wiley.com/journal/15585646">Evolution</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Black-eyed peas could reduce the need for fertilizer

In a recent study from UC Riverside researchers investigated whether...

Since rapid eye movement (REM) <a href="https://www.earth.com/news/deep-sleep-improves-memory-formation-and-recall/">sleep</a> brings about brief, period awakenings, scientists such as Dr. Frederick Snyder in the 1960s have assumed that this type of sleep could have a “sentinel” function, helping animals prepare a fight or flight response at the approach of predators. Until recently though, there has been no experimental evidence for this hypothesis. A new study led by the <a href="http://english.siat.cas.cn/">Shenzhen Institute of Advanced Technology</a> (SIAT) in China could be the first to offer such empirical proof.



By exposing sleeping mice to a trimethylthiazoline (TMT) odor, a stimulus indicating the presence of a predator, the researchers discovered a common brain circuit regulating both REM sleep and innate fear mechanisms.&nbsp;



"TMT triggered rapid arousal from REM sleep but not from non-rapid-eye-movement sleep. This suggests that REM sleep has specific properties that allow rapid arousal in response to predatory stimuli," said study lead author Dr. Liping Wang, a neuroscientist at SIAT.



Dr. Wang and his colleagues discovered that the brain circuits activated during REM sleep consist of the medial subthalamic nucleus (mSTN), a region that contains a high density of corticotropin-releasing hormone (CRH) neurons, which have a crucial role in initiating and structuring stress responses.&nbsp;



By combining in vivo neural activity recording and cell-type specific manipulations, the scientists found that the mSTN-CRH neurons were responsible for a lowered arousal threshold during REM sleep, and increased defensive responses after awakening. Moreover, repeated exposures to predator cues induced an increase in total REM sleep time, but shorter duration of REM sleep episodes and a higher fragmentation of sleep architecture.



These findings show how evolutionary processes can lead to two distinct but related functions for the same group of neurons. "We may hypothesize that natural selection favors optimizing existing neural circuitry for efficiency in signal transduction and energy usage over metabolically more expensive solutions,"&nbsp;explained Dr. Wang.



Since the co-occurrence of increased REM sleep and stress-related mood disorders has already been observed in clinical studies, this new study could be a step forward in designing novel therapeutic frameworks.&nbsp;



“Our study raises the question of whether it is possible to treat mood disorders by targeting the common regulatory circuit of sleep and fear. We will continue working on this question,"&nbsp;concluded Dr. Wang.



The study is published in the journal <a href="https://dx.doi.org/10.1016/j.neuron.2021.12.033">Neuron</a>.&nbsp;&nbsp;



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

REM sleep may help protect against predator attacks

Since rapid eye movement (REM) sleep brings about brief, period...

Walking seems to be one of the most natural of movements. Yet, neuroscientists have struggled for decades to understand how our nervous system coordinates the complex interplay of nerves and <a href="https://www.earth.com/news/cigarette-smoke-damages-muscles/">muscles</a> that structures locomotion.&nbsp;



Until recently, researchers assumed that a large diversity of neuronal circuits in the brain are responsible for handling this process. However, a new study led by <a href="https://www.columbia.edu/">Columbia University</a> has found that a single type of neurons – the ventral spinocerebellar tract neurons - are completely responsible for keeping our legs in lockstep.



“As one might expect, it’s the brain that initiates locomotion. But it doesn’t coordinate it,” said study senior author George Mentis, a neuroscientist at Columbia University who investigates the neural circuits controlling walking in order to find new treatments for patients with health conditions such as spinal cord injuries, amyotrophic lateral sclerosis, or spinal muscular atrophy.



According to Professor Mentis and his colleagues, the coordination of our numerous walking muscles is handled by neurons in the spinal cord. If&nbsp;these ventral spinocerebellar tract neurons were silenced in freely moving adult mice, the animals could not move properly.&nbsp;



Furthermore, if the neurons were activated by light or drugs, they could reliably induce locomotor behavior in juvenile mice. “In other words, these neurons are both necessary and sufficient for locomotor behavior,”&nbsp;said Mentis.



The researchers also discovered that these neurons are highly interconnected, a feature which likely contributes to their capacity to generate the complex rhythmic patterns sustaining locomotion.



These findings could have important applications in medicine, by helping develop novel treatments for patients with motor disorders or spinal cord injuries.



“For example, it may not be enough to reconnect the brain and the spinal cord in people with severed spinal cords,” explained Mentis. 



“Our findings suggest that you would also have to restore proper activity in the ventral spinocerebellar tract neurons to ensure that the central pattern generator is working properly. Everything has to be tightly balanced between exciting certain neurons and inhibiting others. If this balance is compromised, you won’t have coordinated movement.”



The study is published in the journal <a href="https://doi.org/10.1016/j.cell.2021.12.014">Cell</a>.&nbsp;



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Neurons in the spinal cord coordinate walking

Walking seems to be one of the most natural of...

While many animal species, including minks, dogs, cats, hamsters, or lions, can become ill when exposed to <a href="https://www.earth.com/news/cambodian-bats-have-coronaviruses-related-to-sars-cov-2/">SARS-CoV-2</a>, pigs seem to be quasi-immune. Even if they can be infected by the virus when exposed to high doses, the infection is most of the times self-limited and they neither show any clinical symptoms, nor transmit the virus to other animals or to humans. A research team led by <a href="https://www.iastate.edu/">Iowa State University</a> set out to find why are pigs so resistant to infection with the new coronavirus.



By introducing the virus to cultured porcine and human respiratory epithelial cells, the researchers found that pig cells underwent “apoptosis” (or controlled cell death) in response to infection at a much higher rate than human respiratory cells.&nbsp;



“When we looked under the microscope there was an interesting phenomenon going on inside the cells,” said study lead author Rahul Nelli, a research assistant professor of Veterinary Diagnostic and Production Animal Medicine at Iowa State University. “The nuclei of the infected pig cells were starting to shred into fragments, but not those of the uninfected pig cells.”



According to the scientists, this shredding of the nucleus of infected cells (a telltale sign of apoptosis) soon after the coronavirus entered the cells causes minimal tissue damage and confines viral replication, thus significantly limiting severe illness.&nbsp;



While human cells can also undergo apoptosis in response to coronavirus infection, they are roughly 100 times less likely to do this than porcine cells. Instead, human cells more often go through necrosis, another form of cell death that is less controlled than apoptosis and can trigger dangerous hyperimmune reactions.



“We don’t want to over-conclude, but apoptosis is probably something intrinsic to the pig immune system that is innate and not acquired,” explained study co-author Luis Giménez-Lirola, an associate professor of Veterinary Diagnostic at Iowa State University. “The idea is to kill the virus subtly but fast enough so there’s not an excessive immune response triggered.”



Further research could lead to therapies designed to trigger apoptosis in human cells, and thus help patients avoid severe illness. A first step in this direction would be to identify all the genes activated during the infection process and compare them to those of animal species that appear to be more resistant to COVID-19.&nbsp;



The study is published in the journal <a href="https://www.nature.com/articles/s41420-021-00781-w">Cell Death Discovery</a>.



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Pigs are highly resistant to SARS-CoV-2 infection

While many animal species, including minks, dogs, cats, hamsters, or...

Humans have a highly complex culture that enables them to transmit knowledge and learn various types of <a href="https://www.earth.com/news/dogs-exhibit-behaviors-similar-to-human-adhd/" data-type="news" data-id="1897151">behaviors</a> from others. Thus, since skills and technologies tend to accumulate over generations and become increasingly intricate and efficient, human culture can be described as cumulative.&nbsp;



Until recently, scientists thought that non-human primates are very different and need to reinvent cultural behaviors individually. However, new field research led by the <a href="https://www.uzh.ch/en.html">University of Zurich</a> has found that chimpanzees may be more similar to humans than previously thought in terms of their ability of transmitting and learning cultural behaviors.



To explore this problem, a team of primatologists carried out a series of field experiments in the Nimba Mountains of Guinea in order to assess whether chimps can invent by themselves a complex behavior such as nut cracking independently. First, the chimps were shown oil palm nuts and stones. Next, the scientists added a palm fruit to the experimental setup. Afterwards, the nuts were cracked open and placed above the stones. And finally, the chimps were presented with another, easier-to-crack type of nuts (Coula) together with stones.



A total of 35 chimpanzee groups visited the experiments, of which 11 parties investigated closely and attentively the experimental items. However, even after years of exposure to these materials, the chimpanzees were unable to learn how to use the stones in order to crack nuts, no matter how much interest they shown in investigating the experimental items. These results suggest that, without a model to teach them how to open the nuts, the chimps are unable to learn by themselves such behaviors.



“Our findings suggest that chimpanzees acquire cultural behaviors more like humans and do not simply invent a complex tool use behavior like nut cracking on their own,” said study lead author Kathelijne Koops, a professor of Anthropology at the University of Zurich.



“Our findings on wild chimpanzees, our closest living relatives, help to shed light on what it is (and isn’t!) that makes human culture unique. Specifically, they suggest greater continuity between chimpanzee and human cultural evolution than is normally assumed and that the human capacity for cumulative culture may have a shared evolutionary origin with chimpanzees,” she concluded.



The study is published in the journal <a href="https://dx.doi.org/10.1038/s41562-021-01272-9">Nature Human Behavior</a>.&nbsp;



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Chimpanzees may be more similar to humans than expected

Humans have a highly complex culture that enables them to...

Anthropogenic climate change has caused major disturbances to marine ecosystems worldwide. Marine heatwaves have been particularly damaging, leading to mass mortalities of organisms and other deleterious effects. Prolonged rises in ocean temperature (for a few days or weeks) have devastating effects on habitat-forming species, including reef-building corals, sponges, gorgonians, <a href="https://www.earth.com/news/seagrass-wasting-disease-is-fueled-by-climate-change/" data-type="news" data-id="1899672">seagrasses</a> and kelps. These organisms are major contributors to ecosystem structure and functioning, mostly through the provision of habitat, food, and shelter for other, associated reef species.&nbsp;



In the summer of 2003, a severe marine heatwave (MHW) impacted the NW Mediterranean Sea with temperatures up to 3°C above the average. During this event, several populations of&nbsp;red gorgonian&nbsp;(Paramuricea clavate)&nbsp;and the red coral&nbsp;(Corallium rubrum)&nbsp;suffered mass mortality. Scientists in the region initiated research to monitor the recovery of five impacted populations of these coral reef species from Scandola marine protected area in Corsica, France.&nbsp;



The 15-year study, led by researchers from the University of Barcelona, has revealed that populations of P. clavata and C. rubrum - species that are essential for creating complex habitats on coral reefs - have failed to recover after successive marine heatwaves. The biomass of these species declined by between 80 and 90 percent during the study period.&nbsp;



This is the first study to assess the long-term recovery capacity of populations of these two important species of Mediterranean coral. Initially, the research focused on changes in density, biomass and size structure of these species in the highly protected Scandola marine reserve, as the scientists aimed to provide insights into the recovery capacity of these important reef species.&nbsp;



These are long-lived species that can survive for more than a hundred years in some cases. Their population dynamics are characterized by slow growth and recruitment rates, and individuals take a long time (sometimes up to 10 years) to reach sexual maturity. These statistics indicate that populations of the species may take a long time to recover from ecological disturbances, especially when mortality of adult reproductive colonies across populations is high.



Far from recording recovery, the researchers monitoring populations of P. clavata and C. rubrum witnessed the slow collapse of these species. Fifteen years after the 2003 MHW event, these populations are considered to be practically extinct from a functional perspective.



“We observed an average biomass loss regarding the initial biomass of 80% in populations of red gorgonian, and up to a 93% regarding the studied population of red coral,”&nbsp;noted Daniel Gómez, researcher at ICM-CSIC.



“These data are worrying for the conservation of these emblematic species, and it indicates that the effects of the climate crisis are speeding up, with obvious consequences for the submarine landscapes, where the loss of coral equals the loss of trees in forests,”&nbsp;said Joaquim Garrabou, also member of ICM-CSIC.



Unfortunately, the initial heatwave in 2003 was followed by subsequent warm water events in at least four of the years in the study period: 2009, 2016, 2017 and 2018. These marine heatwaves are clearly becoming more frequent and this is not helping the recovery of the long-lived reef species under investigation.



“We believe one of the main reasons why we observed these collapse trajectories is the potential recurrent exposure to heatwaves, incompatible with the slow populational dynamics of these species," said Cristina Linares, a professor at the Department of Evolutionary Biology, Ecology and Environmental Sciences.



“During these heatwaves, the temperature conditions in the studied area reached extreme levels which are incompatible with the life of these corals, which probably caused new mortality events to the decimated populations and made the recovery impossible.”



As the effects of climate change intensify, the frequency and strength of marine heatwaves is set to increase, which could spell disaster for may coral populations, both in the Mediterranean and on reefs worldwide.&nbsp;



“However, there will probably be some areas in the Mediterranean in which, due to several factors, the recurrence of such climate impacts may be lower. This makes it especially relevant to keep – regarding other potential impacts – these climate refuges where the trajectories of coral populations could be more positive than those observed in this study,”&nbsp;noted the study authors.



“Nevertheless, there is an urgent need for stronger measures to be implemented against the climate crisis before the loss of biodiversity becomes irreplaceable."



The research is published in the journal <a href="https://royalsocietypublishing.org/journal/rspb">Proceedings of the Royal Society B Biological Sciences</a>.&nbsp;



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Mediterranean coral populations collapse after repeated heatwaves

Anthropogenic climate change has caused major disturbances to marine ecosystems...

Understanding and navigating social relationships are essential skills for surviving in human societies. From a very young age, <a href="https://www.earth.com/news/young-children-appreciate-humor-in-the-same-brain-region-as-adults/">children</a> need to learn which people they can most count on from the ones surrounding them. According to new research led by the <a href="https://www.mit.edu/">Massachusetts Institute of Technology</a> (MIT), children are able to determine whether people have a strong relationship and a mutual obligation to help each other if they share food, kisses, or other activities which involve sharing saliva.



In human societies, people distinguish between “thin” and “thick” relationships. The latter, usually occurring among family members, are characterized by strong levels of attachment, obligation, and responsiveness. According to anthropologists, people involved in thick relationships are more open to share bodily fluids such as saliva.



“That inspired both the question of whether infants distinguish between those types of relationships, and whether saliva sharing might be a really good cue they could use to recognize them,”&nbsp;said study lead author Ashley Thomas, a postdoctoral fellow in Cognitive Neuroscience at MIT.



“One reason why this distinction between thick and thin might be important for infants in particular, especially human infants, who depend on adults for longer than many other species, is that it might be a good way to figure out who else can provide the support that they depend on to survive.”



Dr. Thomas and her colleagues observed toddlers and babies as they watched interactions between human actors and puppets. In the first set of experiments, an actor shared an orange with a puppet, while another one tossed a ball to the puppet. After the children watched the interactions, the scientists observed their reaction when the puppet showed distress while standing between the two actors. They discovered that the children tended to look first at the actor with whom the puppet shared the orange. According to previous studies on nonhuman primates, this meant that children were expecting help from that person.



In a second set of experiments, focused more specifically on saliva sharing, the actor either placed her finger in her mouth and then in the puppet’s mouth, or placed her finger on her forehead and then on the puppet’s forehead. When the actor showed distress, children expected the puppet with which she shared saliva to be the one to help, as in the previous case.



These findings suggest that saliva sharing is a crucial clue that helps infants learn about social relationships. Since the first set of the experiments was performed before the <a href="https://www.earth.com/news/omicron-is-starting-to-peak-in-the-united-states/">Covid-19 pandemic</a>, and the second one more recently, pandemic-related hygiene concerns did not seem to affect the outcome. Further research is needed though to understand the impact of such concerns on how current and future generations of infants navigate their social spheres.&nbsp;&nbsp;



The study is published in the journal <a href="https://dx.doi.org/10.1126/science.abh1054">Science</a>.



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Children use saliva sharing to infer close relationships

Understanding and navigating social relationships are essential skills for surviving...

A new study led by the <a href="https://www.awi.de/en/">Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research</a> has found that increases or decreases in the volume of the Greenland Ice Sheet (GrIS) significantly lag climate changes. These findings suggest that our current <a href="https://www.earth.com/news/new-rainfrog-named-after-climate-activist-greta-thunberg/">climate</a> could still influence the size of the ice sheet thousands of years later.



Scientists all over the world fear that one of the effects of global warming will be the melting of the GrIS, a phenomenon expected to lead to dangerous <a href="https://www.earth.com/news/sea-levels-are-rising-at-an-alarming-rate/">sea level rises</a>, which may negatively impact a large number of ecosystems. However, since observational studies of the status of GrIS span only a few decades, there are still great uncertainties regarding the speed and amount of its future disintegration.



By using computer models to simulate the evolution of the GrIS from the last interglacial period to the end of the 21st century, scientists have found that the gradual cooling of our planet which started after the extremely hot period called the “<a href="https://www.ncdc.noaa.gov/global-warming/mid-holocene-warm-period">Holocene Thermal Maximum</a>” (dating 10,000 to 6,000 years ago) has influenced for thousands of years the dimensions and dynamics of the GrIS, and still has a strong impact today.



“Given that Greenland’s climate was getting colder from the Holocene Thermal Maximum to the Pre-Industrial era, our simulation implies that the GrIS experienced a background growth from the mid-Holocene to the industrial era. Due to this background trend, the GrIS still gains mass until the second half of the 20th century, even though anthropogenic warming begins around 1850 AD,” explained the study authors.



“Our results highlight that the present evolution of the GrIS is not only controlled by the current climate change, but also affected by paleoclimate, especially the relatively warm Holocene climate. We propose that the GrIS was not in equilibrium throughout the entire Holocene and that the slow response to Holocene climate needs to be represented in ice sheet simulations in order to predict ice mass loss, and therefore sea level rise, accurately.”



These findings imply that the current climate changes that we experience will have a much longer and less predictable impact on the state of the GrIS. Further research is needed to better understand the long-term impacts of climate, and thus to properly predict future changes in our planet’s geography and ecosystems.



The study is published in the journal <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0259816">PLoS One</a>.



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Greenland has a delayed response to climate change

A new study led by the Alfred Wegener Institute Helmholtz...

Thecodontosaurus was one of the first <a href="https://www.earth.com/news/jaws-of-predatory-dinosaurs-grew-stronger-as-they-evolved/">dinosaurs</a> to evolve (around 205 million years ago) and one of the first to be discovered and formally described by scientists. Despite this long history, the small, bipedal dinosaur is still subject to exciting new research.&nbsp;



Part of the mystery of Thecodontosaurus is that this diminutive, bipedal dinosaur is the ancestor of the massive, quadrupedal sauropods. In a new paper published in <a href="https://royalsocietypublishing.org/journal/rsos">Royal Society Open Science</a>, researchers reconstructed Thecodontosaurus’ limb muscles. In reconstructing the muscle structure, the scientists were able to unlock the mystery of how small dinosaurs evolved into massive behemoths.&nbsp;



"The <a href="https://www.bristol.ac.uk/">University of Bristol</a> houses a huge collection of beautifully preserved Thecodontosaurus fossils that were discovered around Bristol," said study lead author Antonio Ballell, a PhD student in the School of Earth Sciences. "The amazing thing about these fossilized bones is that many preserve the scars and rugosities that the limb musculature left on them with its attachment."



Not only is especially good fossil preservation needed for musculature reconstruction, a close study on the muscle structure of living relatives is needed as well.&nbsp;



"In the case of dinosaurs, we have to look at modern crocodilians and birds, that form a group that we call archosaurs, meaning 'ruling reptiles,' said Ballell. "Dinosaurs are extinct members of this lineage, and due to evolutionary resemblance, we can compare the muscle anatomy in crocodiles and birds and study the scars that they leave on bones to identify and reconstruct the position of those muscles in dinosaurs."



"These kinds of muscular reconstructions are fundamental to understand functional aspects of the life of extinct organisms," said study co-author Professor Emily Rayfield. "We can use this information to simulate how these animals walked and ran with computational tools."



The reconstruction of Thecodontosaurus paints the image of an agile dinosaur that used its forelimbs for grasping rather than walking. There are also hints of the musculature necessary for the massive sauropods that evolved later, even in this early dinosaur.&nbsp;



"From an evolutionary perspective, our study adds more pieces to the puzzle of how the locomotion and posture changed during the evolution of dinosaurs and in the line to the giant sauropods," said study co-author Professor Mike Benton.



"How were limb muscles modified in the evolution of multi-ton quadrupeds from tiny bipeds? Reconstructing the limb muscles of Thecodontosaurus gives us new information of the early stages of that important evolutionary transition."



---



By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Muscular reconstruction shows how dinosaurs moved

Thecodontosaurus was one of the first dinosaurs to evolve (around...

When a breeder of tarantulas noticed, in 2018, that several of his spiders were becoming sick and dying, he approached parasitologist Adler Dillman from the <a href="https://www.ucr.edu/">University of California, Riverside</a>. The ailing tarantulas were characterized by what appeared to be a white discharge in and around the oral cavity. On closer inspection, however, it became clear that the white mass was a large infestation of nematode <a href="https://www.earth.com/news/worms-without-ears-can-hear-through-their-skin/">worms</a> intertwined together inside and around the spider’s mouth.&nbsp;



Dillman and his colleagues examined the worms and, based on a combination of morphological and morphometrical data, and unique DNA sequences, they identified a new species of nematodes. There are more than 25,000 different species of nematode worms and they are among the most abundant animals on Earth. They parasitize a wide range of living organisms, but this is only the second time that a species has been found to infect tarantulas.



The scientists named the new species Tarantobelus jeffdanielsi, after Jeff Daniels, the American actor, musician and producer. They named it in Daniels’ honor because his character in the 1990 film ‘Arachnophobia’ saves a town from a deadly infestation of spiders.&nbsp;



“His character in the film is a spider killer, which is exactly what these nematodes are,” said Dillman, who led the team that discovered the nematode.



“When I first heard a new species of nematode had been named after me, I thought, ‘Why? Is there a resemblance?’” joked Daniels. “Honestly, I was honored by their homage to me and 'Arachnophobia.' Made me smile. And of course, in Hollywood, you haven’t really made it until you’ve been recognized by those in the field of parasitology.”



The scientists investigated the lifecycle of the worms, and where exactly they resided in the infected spiders. They found that infestations of worms occurred in the mouth area and on the pedipalps, special appendages near the mouth that the spiders use to sense and manipulate food. No worms were found in the stomachs of infected spiders.&nbsp;



Once infected, spiders lost the ability to use their jaws and feed themselves, and began to show strange behavior, such as walking on the very tips of their legs. The infection would ultimately prove fatal for a tarantula, as it would starve to death.&nbsp;



“It may take months because tarantulas don’t have to eat particularly often. However, if they get this infection, they will die of starvation,” Dillman said.&nbsp;



When culturing the nematode worms in the laboratory, the researchers noted that they ate bacteria such as E. coli and did not appear to feed off the parasitized spiders themselves. This led the researchers to conclude that the worms may be feeding on the bacteria found around the oral cavity of the spider.&nbsp;



However, there is not yet an understanding of how the worms change tarantula behavior or render the pedipalps and jaws non-functional. Dillman is planning additional studies to investigate this, as well as how breeders can treat or even prevent infections in their captive-bred tarantulas.



The researchers found that the average lifespan of jeffdanielsi nematodes in the laboratory was 11 days. These worms are mostly hermaphrodites – each individual produces sperm as well as eggs. Furthermore, they fertilize themselves and each produces approximately 160 offspring within its 11-day lifespan.



Although this is only the second time that nematode parasites have been found infecting tarantulas, Dillman feels this reflects the fact that little research is done on these spiders. Nematode worms are very common parasites and it would be unusual if there were no species that parasitized tarantulas.



“Nematodes have been around for hundreds of millions of years. They’ve evolved to infect every kind of host on the planet including humans,” he said. “Any animal you know of on planet Earth, there’s a nematode that can infect it.”



The team’s work describing jeffdanielsi has recently been&nbsp;<a href="https://meridian.allenpress.com/journal-of-parasitology/article-abstract/108/1/30/476785/TARANTOBELUS-JEFFDANIELSI-N-SP-PANAGROLAIMOMORPHA?redirectedFrom=fulltext">published</a>&nbsp;in the&nbsp;<a href="https://meridian.allenpress.com/journal-of-parasitology">Journal of Parasitology</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Scientists have discovered worms that kill tarantulas

When a breeder of tarantulas noticed, in 2018, that several...

Protecting 30 percent of land and <a href="https://www.earth.com/news/ocean-heat-reached-a-record-high-for-the-sixth-straight-year/">sea</a> by 2030 is an important benchmark, but it will not be enough to halt and reverse biodiversity loss, according to a team of more than 50 scientists from 23 countries. 



The experts delivered a synthesis of the science supporting 21 targets in a draft of the <a href="https://www.cbd.int/article/draft-1-global-biodiversity-framework">Post-2020 Biodiversity Framework</a>, a plan being negotiated by the United Nations.



The scientists are calling for systematic changes, including substantial reductions in damaging fisheries and farming subsidies, great reductions in overconsumption, and limiting global warming to 1.5°C.&nbsp;



Paul Leadley, a professor at Paris-Saclay University, is also an assessment leader and past chair of <a href="http://www.biodiscovery.com/">BioDISCOVERY</a>.



“The target of protecting 30% of all land and seas is important and attracting a lot of attention. And expanding protected areas is a good start if done well, but far short of what's needed to halt and reverse biodiversity loss - called ‘bending the curve’ for biodiversity."



"There’s very good evidence that we will fail again to meet ambitious international biodiversity objectives if there’s too much focus on protected areas at the expense of other urgent actions addressing the threats to biodiversity.”&nbsp;



“Governments are clearly struggling with the breadth and depth of the ‘transformative changes’ needed to bend the curve for biodiversity, and sometimes seem unwilling to face up to it.&nbsp; But deep changes are necessary and will greatly benefit people in the long run.”



The key points highlighted in the study were that reversing biodiversity loss requires transformative change, coordinated at every level. Along with these changes, assessments must be carried out and greater monitoring efforts funded. Perhaps most importantly, action must be taken immediately to be impactful.&nbsp;



“The sooner we act the better. Time lags between action and positive outcomes for biodiversity can take decades so we must act immediately and sustain our efforts if we are to reach the global goals by 2050," said study co-author Maria Cecilia Londoño Murcia of the Humboldt Institute.



"The time needed for safeguarding and restoring ecosystem structure, function and resilience is particularly critical for people and communities whose livelihoods and well-being directly depend on these systems and the benefits they provide.”&nbsp;



---By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Sweeping changes needed to reverse biodiversity loss

Protecting 30 percent of land and sea by 2030 is...

Insects don’t have noses and are not able to “smell” the roses in the familiar sense of the word. Instead, most odor molecules are detected by chemoreceptors that occur on an insect’s antennae. Using these chemical receptors, insects are capable of perceiving and differentiating between thousands of&nbsp;airborne compounds. They use these chemical signals to locate forage <a href="https://www.earth.com/news/some-plants-wont-survive-the-loss-of-seed-dispersing-animals/">plants</a> and mates, as well as to avoid predators.



But now, new research indicates that common air pollutants present in rural and urban environments may be hampering the ability of insects to detect the chemical signals so crucial to their activity as pollinators.&nbsp;



A team of scientists from the <a href="http://www.reading.ac.uk/">University of Reading</a> has conducted the first study to observe that common air pollutants, including diesel exhaust fumes and ozone, have a negative impact on the success of pollination by insects.&nbsp;



“We knew from our previous lab studies that diesel exhaust can have negative effects on insect pollinators, but the impacts we found in the field were much more dramatic than we had expected," said Dr. Robbie Girling, who led the project.



These previous laboratory studies by members of the Reading team showed that&nbsp;chemicals in <a href="https://www.reading.ac.uk/news-archive/press-releases/pr649662.html">diesel fumes react with and can change the scents of flowers such that the insects cannot locate the flowers. </a>The research suggested that pollution could contribute to the ongoing declines in pollinating insects, by making it harder for them to locate the pollen and nectar that form their food.



In the new study, the researchers aimed to gather evidence showing how air pollution affects different species of pollinating insects, some of which rely on scent more heavily than others.



The study, funded by the Natural Environment Research Council, used a purpose-built fumigation facility to regulate levels of nitrogen oxides (NOx) – present in diesel exhaust fumes – and ozone in an open field environment. They then observed the effects these pollutants had on the pollination of black mustard plants by free-flying, locally-occurring pollinating insects over the course of two summer field seasons.



Although the experiments made use of pollution levels that were way below the maximum acceptable levels considered as safe in the US, the results of the field experiments were dramatic. The researchers observed 62 to 70 percent fewer pollinator visits to the plants located in polluted air. This reduction was seen in seven different groups of pollinators, including bees, moths, hoverflies and butterflies.&nbsp;



There were also 83 to 90 percent fewer visits to flowers by these insects, and ultimately a 14 to 31 percent reduction in pollination success, based on the measurement of seed yield and other factors.



“The findings are worrying because these pollutants are commonly found in the air many of us breathe every day," said Dr. James Ryalls. "We know that these pollutants are bad for our health, and the significant reductions we saw in pollinator numbers and activity shows that there are also clear implications for the natural ecosystems we depend on.”



Insects are important pollinators of crops upon which we depend for food and so a reduction in pollinating activity could have far-reaching economic and social consequences. Around 70 percent of crop species rely on insects for pollination; these include apples, strawberries and cocoa.&nbsp;



In addition, pollination supports around eight percent of the total value of agricultural food production, worldwide. The pollinating activity of insects thus generates hundreds of billions of pounds worth of economic value each year.&nbsp;



Furthermore, far higher levels of air pollutants are found in many areas around the world where people and businesses breach the regulations. For example, a&nbsp;<a href="https://www.independent.co.uk/climate-change/news/air-pollution-england-defra-labour-who-nitrogen-dioxide-luke-pollard-b404484.html?r=55147">2019 analysis</a> recorded illegal levels of nitrogen dioxide present in local authorities, in large areas of northern England (including Cheshire and Gateshead), and in southern England (including Wiltshire, Chichester and rural areas such as the New Forest).



“This truly cross-disciplinary work demonstrated very clearly how atmospheric pollutants negatively impact on pollination with direct consequences for food production as well as the resilience of our natural environment," concluded study co-author Dr. Christian Pfrang.



Their results are published today in the <a href="https://doi.org/10.1016/j.envpol.2022.118847">&nbsp;journal&nbsp;</a><a href="https://www.journals.elsevier.com/environmental-pollution">Environmental Pollution</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Air pollutants confuse pollinators and reduce food production

Insects don’t have noses and are not able to “smell”...

In a new study from <a href="https://wsu.edu/">Washington State University</a> (WSU), experts have found that a high protein diet increases the risk of kidney <a href="https://www.earth.com/news/coffee-stimulates-digestion-and-protects-against-disease/">disease</a> and premature death among captive polar bears. 



Previous studies have suggested that there is a similar link between kidney disease and excessive protein consumption among humans. The Mayo Clinic reports that a high-protein diet may worsen kidney function in humans, particularly in the long term, because the body may struggle to eliminate all the waste products.



A research team led by WSU wildlife biologist Charlie Robbins investigated what zoos have typically been feeding polar bears. The study revealed that their diet usually consists of a food ratio intended for big cats, containing about two to three parts protein to one part fat. This diet is the opposite of what polar bears would be eating in the wild.&nbsp;



“Zoos made some assumptions in the past about the nutritional requirements of polar bears because their diet is almost exclusively animals,” said Professor Robbins. “But, unlike cats, they do not need and cannot tolerate high protein.”



Even though polar bears are carnivores that feed mainly on seals, researchers have found that they have physiology that is more closely aligned with humans and other omnivores.



Looking at death records of captive polar bears, the researchers discovered that the most common cause of death was kidney disease. Bears with fatal kidney disease died 10 years earlier than bears without the condition. The second most common causes of death were liver disease and cancer, according to the analysis.&nbsp;&nbsp;



Out of more than 600 bears examined in the wild, the team found no evidence kidney disease.



“A slate of early deaths across sexes that is limited to two major organs raised several red flags for us,” said Professor Robbins, who has researched both grizzly and polar bear nutrition for more than 35 years.



Former WSU graduate student Karyn Rode conducted field studies which showed that wild polar bears prefer a diet that is two parts fat to one part protein.



“Although we knew that polar bears selected for the blubber of their prey, this was the first time we were able to quantify how much fat they were actually consuming,” said Professor Robbins. “When it comes to feeding polar bears, the general mindset has been that they are carnivores. No one has really been paying attention to the amount of protein they might need, much less limitations on how much they might tolerate.”



In the current paper, the researchers propose that - like humans - both polar and grizzly bears require relatively low levels of protein. When captive bears were offered their choice of blocks made up of pure lard and blocks made up of high protein meat, they ultimately consumed the same ratio of fat to protein as their relatives in the wild.



The study authors recommend that zoos should adopt alternative foods for captive polar bears that mimic the fat-protein ratio found naturally in the wild. Once these alternatives are introduced, monitoring the animals could help experts determine whether the new diets may improve their health and longevity.



The study is published in the journal <a href="https://onlinelibrary.wiley.com/journal/10982361">Zoo Biology</a>.



---



By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

High protein diet causes kidney disease in polar bears

In a new study from Washington State University (WSU), experts...

There are a few species of beetles that can jump, but beetle larvae tend to squirm across the substratum and have never been seen doing acrobatic jumps -- until now.



A team of researchers has published a scientific article documenting the jumping behavior of larval lined flat bark beetles (Laemophloeus biguttatus). This type of <a href="https://www.earth.com/news/animal-locomotion-natural-energy/">locomotion</a> has not been recorded for beetle larvae before. 



The larvae are able to spring into the air with a speed of around 0.5 meters per second, and to travel forwards a distance approximately equivalent to four times their own body length. While flying through the air, the larva curls itself into a loop and as it lands, it bounces and rolls along until it becomes stationary.&nbsp;



“Jumping at all is exceedingly rare in the larvae of beetle species, and the mechanism they use to execute their leaps is – as far as we can tell – previously unrecorded in any insect larvae,” said study co-author Matt Bertone, director of <a href="https://www.ncsu.edu/">North Carolina State University</a>’s Plant Disease and Insect Clinic.&nbsp;



“The way these larvae were jumping was impressive at first, but we didn’t immediately understand how unique it was,” said Bertone. “We then shared it with a number of beetle experts around the country, and none of them had seen the jumping behavior before. That’s when we realized we needed to take a closer look at just how the larvae was doing what it was doing.”



Usually when insects make impressive jumps, they rely on a “latch-mediated spring actuation mechanism.” This means that two parts of the body latch onto each other while the insect exerts force using its muscles. When this builds up a significant amount of potential energy, the insect unlatches the two parts and all the stored energy is released at once. This results in an action-packed spring off the ground.



The researchers looked for a two-part latch mechanism on the surface of the lined flat bark beetle larvae and found nothing. Then, they used microCT scans to measure how much muscle the beetle larvae had and calculated whether this would provide enough power to launch the larvae into the air at a speed of 0.5 meters per second. The larvae did not have enough muscle to achieve this by muscle action alone.&nbsp;



The conclusion was that the larvae must be using some form of spring-loaded system to achieve their acrobatic jumps. This is when Bertone and study co-author Adrian Smith decided to film the behavior in order to get a better understanding of what was taking place. Smith is a research assistant professor of biological sciences at NC State and head of the Evolutionary Biology &amp; Behavior Research Lab at the North Carolina Museum of Natural Sciences.



The team filmed some jumps at 60,000 frames per second and were able to see that the beetle larvae actually hook their feet into the ground as they arch their bodies and prepare to jump. As soon as one foot loses its grip on the ground, the spring is released and the larva is propelled into the air under the power of its body’s own potential energy store.



“What makes the&nbsp;L. biguttatus&nbsp;so remarkable is that it makes these leaps without latching two parts of its body together,” said Bertone. “Instead, it uses claws on its legs to grip the ground while it builds up that potential energy – and once those claws release their hold on the ground, that potential energy is converted into kinetic energy, launching it skyward.”



Meanwhile, in&nbsp;<a href="https://www.youtube.com/watch?v=SEst5RERHJ4">an unrelated video about jumping maggots</a>, Smith had included a short clip of the jumping behavior in&nbsp;L. biguttatus. That video was seen by Takahiro Yoshida, a researcher from Tokyo Metropolitan University in Japan, who had witnessed similar jumps in the larvae of another beetle species called&nbsp;Placonotus testaceus, but had not published anything related to the behavior. Yoshida is a co-author on the publication about this unusual form of locomotion.



“We don’t have high-speed footage of&nbsp;P. testaceus, but the video evidence we do have from Yoshida’s lab suggests that this previously unknown behavior is found in two different genera which are not even closely related,” said Bertone.



“This raises a lot of questions. Has this behavior evolved separately? Is it found in other beetle species? Are these genera more closely related than we previously suspected? There’s a lot of interesting work to be done here.”



Details of this unusual method of locomotion in lined flat bark beetle larvae are published today in the journal <a href="https://journals.plos.org/plosone/">PLOS ONE</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Unusual jumping behavior recorded in beetle larvae

There are a few species of beetles that can jump,...

A new study from the <a href="https://www.ubc.ca/">University of British Columbia</a> has revealed that 45 percent of the fish that cross through two or more exclusive economic zones (EEZs) will shift their movement patterns by 2100. This is expected to possibly bring international conflict.&nbsp;



By 2030, 23 percent of these fish are predicted to change their historic ranges. By 2100, this increases to 45 percent of the transnational fish, along with 81 percent of EEZs seeing at least one species shift. The culprit for these changes is, of course, human-caused climate change.&nbsp;&nbsp;&nbsp;&nbsp;



“This is not only an issue of stocks leaving or arriving to new EEZs, but of stocks that are shared between countries, completely changing their dynamics,” said study lead author Dr. Juliano Palacios-Abrantes, who conducted the study while at UBC’s Institute for the Oceans and Fisheries (IOF).&nbsp;



“We will see even more dramatic changes by 2030 and onwards, given current emissions rates. Many of the fisheries management agreements made to regulate shared stocks were established in past decades, with rules that apply to a world situation that is not the same as today.”



The researchers tracked the changing ranges of 9,132 transnational fish populations, which account for 80 percent of the catch from the world's exclusive economic zones. The research started in 2006 and continued forward with projections predicted up to 2100.&nbsp;&nbsp;



“By providing estimates of the size and timing of projected shifts, our study offers tangible reference points around which to consider climate change impacts and negotiate fair policies for sustainable management” said study co-author Dr. Colette Wabnitz, lead scientist at Stanford’s Center for Ocean Solutions.



“We must accept that climate change is happening, and then move fast enough to adapt fisheries management regulations to account for it,” said co-author Dr. Gabriel Reygondeau, a research associate at IOF.



The scientists hope their study can create a framework for international negotiations and planning to create a well designed fisheries management plan for the future. Without this, conflict, even violent conflict could arise over dwindling fish populations supporting a hungry human populace.&nbsp;



The study is published in the journal <a href="https://onlinelibrary.wiley.com/journal/13652486">Global Change Biology</a>.&nbsp;



---



By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Nearly half of the world’s shared fish are on the move

A new study from the University of British Columbia has...

A new study published in the journal <a href="https://www.pnas.org/content/119/2/e2023340118">Proceedings of the National Academy of Sciences</a> has found that the mechanisms behind the sense of <a href="https://www.earth.com/news/how-can-a-smell-transport-us-to-another-place/">smell</a> may be far simpler than previously thought. By studying the olfactory sense of locusts, a research team led by the <a href="https://wustl.edu/">Washington University in St. Louis</a> mapped the neuronal underpinnings behind invariant odor recognition.



“The smell of coffee is the same whether it is smelled in a coffee shop or grocery shop (different backgrounds), on a hot day or a cold day (different ambient conditions), after lunch or dinner (different temporal contexts), or using a deep inhalation or normal inhalation (different stimulus dynamics),” explained the study authors.



“This feat of pattern recognition that is still difficult to achieve in artificial chemical sensing systems is performed by most sensory systems for their survival. How is this capability achieved?”



In order to answer this question, the scientists first trained locusts to associate a specific odor with some of their favorite foods, such as blades of grass. After staying without food for a day, the locusts were exposed to a puff of odor (hexanol or isoamyl acetate), then given a blade of grass. After only six such presentations, the locusts learned to open their palps (the sensory appendages close to its mouth) in expectation of food immediately after smelling the “training odorant.”



The researchers then mapped which neurons were activated when the locusts were exposed to the odorant under different environmental conditions, such as in conjunction to other smells, in humid or dry conditions, or when the locusts were fully fed or starving. Even though the locusts opened their palps every time, different patterns of neurons were activated, depending upon each specific context.



"The neural responses were highly variable," said study senior author Baranidharan Raman, a professor of Biomedical Engineering at Washington University. "That seemed to be at odds with what the locusts were doing, behaviorally."



To understand how variable neural responses produced stable behavior, Professor Raman and his colleagues used a machine-learning algorithm that exploited two functional types of neurons: “ON neurons,” which were activated when an odorant was present, and “OFF neurons,” which fired only after the odor presentation had ended.&nbsp;



"You can think of the ON neurons as conveying 'evidence for' an odor being present, and OFF neurons as 'evidence against' that odor being present," explained Professor Raman.&nbsp;



To recognize the presence of an odorant, the scientists simply needed to add evidence for the odorant being present (add the spikes across all ON neurons), and subtract evidence against the odorant being present (add the spikes across all OFF neurons). If the result was above a certain threshold, the machine learning algorithm would reliably predict that the locust smelled the odor and opened its palps.



“We were surprised to find that this simple approach is all that was needed to robustly recognize an odorant,” Professor Raman concluded.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Locusts have a surprisingly simple way of sensing smells

A new study published in the journal Proceedings of the...

Observing animal <a href="https://www.earth.com/news/ocean-acidification-disrupts-the-behavior-of-fish-shoals/">behavior</a> and ecology in the wild is the basis of conservation planning. However, the cost, time commitment, and danger involved in basic observational work can make it extremely challenging.&nbsp;



Scientists often substitute observations with data collected through biologging devices. These high-tech devices can monitor heart rate, breathing, animal movement, and more. To accurately interpret data from logging devices, statistical analysis is needed. Like other scientific technologies, statistical tools are always evolving. A new study from the <a href="https://www.ubc.ca/">University of British Columbia</a> improves on statistical tools used for interpreting data from biologgers.&nbsp;&nbsp;



“The thing we really tackled with this paper was trying to get at some of those fine-scale behaviors that aren’t that easy to model,” said study lead author Evan Sidrow, a doctoral student in the UBC Department of Statistics.&nbsp;



“It’s a matter of finding behaviors on the order of seconds - maybe 10 to 15 seconds. Usually, it’s a matter of a whale looking around, and then actively swimming for a second to get over to a new location. We are trying to observe fleeting behaviors, like a whale catching a fish.”



The researchers improved a statistical tool based on a hidden Markov model, which is used to interpret animal movement datasets.



“Traditional hidden Markov models break down at very fine scales,” said Sidrow. “That’s because there’s structure in the data you can’t capture using the basic type of hidden Markov model. We’re trying to capture it with this model - we’re trying to account for this ‘wigglyness' that a traditional hidden Markov model wouldn’t be able to account for.”



Because modern data logging devices collect data almost continuously, an enormous amount of data points are collected in a relatively short period of time. The Markov model has a hard time interpreting such a large amount of data. The new statistical modeling method allows a finer scale look into the data, which produces greater information for conservation planning by decision makers, including those working on orca conservation.&nbsp;&nbsp;



"As a case study, we use this framework to model the fine-scale kinematic movements of a northern resident killer whale ( Orcinus orca) off the western coast of Canada," wrote the study authors.&nbsp; "Through simulations, we show that our model produces more interpretable state estimation and more accurate parameter estimates compared to existing methods."



According to study senior author Dr. Marie Auger-Méthé, the study is one of the first steps on the road to fully understanding why southern resident killer whales are not faring as well as their northern counterparts.



“Using our methods to detect when the animals are catching prey and to model their energy expenditure will be key to understanding the differences between these neighbouring whale populations,” said Dr. Auger-Méthé.



She explained that the next goal is to understand when the whales are capturing prey and applying the models to both northern and southern resident killer whale populations to see how they are behaving differently.



“The paper offers many ‘building block’ solutions that can be used together or independently,” said Dr. Auger-Méthé. “In essence, we are providing a toolbox to researchers using high-frequency movement data, and other similar high-frequency time series.”



The study is published in <a href="https://onlinelibrary.wiley.com/journal/1708945x">The Canadian Journal of Statistics</a>.



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By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

New statistical tool could improve killer whale conservation

Observing animal behavior and ecology in the wild is the...

Mammals in general are not able to digest cellulose, the carbohydrate that is found in the cell walls of plant cells. Even <a href="https://www.earth.com/news/large-herbivores-must-be-restored-to-balance-ecosystems/">herbivores</a>, such as cows, horses and elephants do not produce the enzyme that breaks down cellulose. Instead, mammals (including humans) need gut microbes to carry out this function and enable them to access the nutrients found inside plant cells.&nbsp;



Giant pandas (Ailuropoda melanoleuca) are unusual because they are bears, in the order Carnivora, but their diet consists entirely of bamboo leaves and shoots. Carnivores have short gastrointestinal tracts, geared for digesting animal flesh, and this makes the herbivorous diet of giant pandas even harder to process efficiently. Pandas are thus heavily dependent on the microbes in their guts for breaking down cells in leaves and shoots to make the contents available.



In the wild, pandas feed on fibrous old bamboo leaves for eight months of the year. This diet is poor in nutrients and contains almost no fat. However, during late spring and early summer the bears feed on new shoots that have a higher nutritional value that enables them to gain weight.&nbsp;



Previous research has shown that the gut microbiome of giant pandas changes between the leaf-eating season and the shoot-eating season. However, there has been no research on the effects of these seasonal changes on the body characteristics or physiology of the pandas.&nbsp;



A study published today in the journal&nbsp;<a href="https://www.cell.com/cell-reports/home">Cell Reports</a> addresses this gap in current understanding and finds that shifts in the gut microbes enable pandas to gain weight and store fat when bamboo shoots are available to eat.&nbsp;



“This is the first time we established a causal relationship between a panda’s gut microbiota and its phenotype,” said study first author Guangping Huang from the <a href="https://english.cas.cn/">Chinese Academy of Sciences</a>. “We’ve known these pandas have a different set of gut microbiota during the shoot-eating season for a long time, and it’s very obvious that they are chubbier during this time of the year.”



The team of scientists, led by Fuwen Wei at the CAS Institute of Zoology, has been studying wild giant pandas living in the Qinling Mountains in central China for decades. The team collected fecal samples from eight adult pandas during the leaf-eating season (14 samples) and the shoot-eating season (15 samples). These were assessed for the presence and numbers of different types of gut microbes.&nbsp;



Wei says that these wild pandas have distinctly different populations of gut bacteria in the two seasons. In particular, a significantly higher abundance of a bacterium called&nbsp;Clostridium butyricum&nbsp;is present in the gut during the shoot-eating season compared with during the leaf-eating season. Gas chromatography-mass spectrometry of the short-chain fatty acids in the feces also revealed that the fatty acids butyrate and acetate were present in greater amounts during shoot-eating season.



Although bamboo leaves and shoots contain almost no fat, pandas were able to gain weight and store fat when they preferentially ate shoots. The bacterium C. butyricum produces the fatty acid butyrate as a product of its metabolism in the gut of the pandas, and the scientists were interested in the effects of this fatty acid on panda metabolism.



To investigate whether the change in gut microbiota could affect a panda’s metabolism, the researchers performed a fecal transplant of panda feces, collected in the wild, to the intestinal tracts of germ-free mice. They introduced fecal matter from panda donors during the leaf-eating season into some mice, while other mice received feces collected from pandas during the shoot-eating season. A third group of mice – the control group – received no panda fecal matter.&nbsp; Then they fed the mice for 3 weeks with a bamboo-based diet that simulated what pandas eat. &nbsp;



The experts found that mice transplanted with panda feces collected during shoot-eating season gained significantly more weight and had more fat after 21 days than mice transplanted with feces from leaf-eating season, despite consuming the same amount of food. Further analysis revealed that the fatty acid butyrate, a metabolic product of&nbsp;C. butyricum, could upregulate (enhance) the expression of a gene called&nbsp;Per2, which increases lipid synthesis and storage. Thus, the mice showed the same patterns of seasonal weight gain as the pandas do, indicating the critical role of the gut microbiome in panda metabolism.



Fat storage is important in many animals that eat a nutrient-poor diet. The bamboo eaten by pandas in the wild is deficient in fat but the shoots, eaten in late spring and early summer, contain higher levels of protein and carbohydrate. The gut bacteria in these mammals enables them to use the protein and additional carbohydrates in the shoots, to synthesize lipids that are then available for storage.&nbsp;



Many animals experience a seasonal shift in gut bacteria as a result of changes in food availability. For example, certain species of monkeys have different gut microbiota in summer, when they eat fresh leaves and fruits, compared with that in winter, when they feed on leaves and tree bark. A similar shift has also been observed in the digestive systems of Hadza people, modern hunter-gatherers living in Tanzania, as the type of available food changes through the year.



The researchers plan to investigate and map out more microorganisms in the panda’s gut in future, and to find out how they affect the animals’ health. “Causal research of host phenotype and gut microbiota in wild animals is just beginning. Identifying what bacteria are beneficial for animals is very important, because one day we may be able to treat some diseases with probiotics,” said Huang.



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Giant pandas’ gut bacteria turn nutrient-poor food into fat

Mammals in general are not able to digest cellulose, the...

The turning blades on wind turbines and drones make a <a href="https://www.earth.com/news/traffic-noise-linked-to-higher-risk-of-dementia/">noise</a>, as do the airfoils used on planes and helicopters. Most of the nose that arises as an object moves through air originates at the trailing edge as air flowing over and under the object meet. The same is true for the noise that a bird’s wings make as it flies overhead – except, of course, in the case of owls. They are renowned for being able to fly silently.



In&nbsp;a quest to design airfoils that produce less noise pollution, researchers from <a href="http://en.xjtu.edu.cn/">Xi'an Jiaotong University</a> mimicked the characteristics of owl wings to inform a new design of airfoil that significantly reduces the trailing-edge noise. Details of the study are published today in the journal <a href="https://aip.scitation.org/journal/phf">Physics of Fluids</a>.



“Nocturnal owls produce about 18 decibels less noise than other birds at similar flight speeds due to their unique wing configuration,” said study co-author Xiaomin Liu. “Moreover, when the owl catches prey, the shape of the wings is also constantly changing, so the study of the wing edge configuration during owl flight is of great significance.”



When air flows over the top of an airfoil-shaped surface, it forms a layer of turbulence. Similarly, air flowing underneath also forms a layer of turbulence, and these two layers meet at the trailing edge of the structure. When they meet and air flows back through the trailing edge, it scatters and radiates noise.&nbsp;



The wing feathers of owls form a serrated edge at the trailing end of the wing, and this is thought to minimize turbulence and the associated noise. Previous studies have explored the use of serrated trailing edges and found that the serrations effectively reduce the noise of rotating airfoils. However, the noise reduction was not universal, depending heavily on the way in which the airfoil was used.



“At present, the blade design of rotating turbomachinery has gradually matured, but the noise reduction technology is still at a bottleneck,” said Liu. “The noise reduction capabilities of conventional sawtooth structures are limited, and some new non-smooth trailing-edge structures need to be proposed and developed to further tap the potential of bionic noise reduction."



The researchers used noise calculation and analysis software to conduct a series of detailed theoretical studies of simplified airfoils that had characteristics reminiscent of owl wings. They applied their findings to suppress the noise of rotating machinery.



The study showed that improving flow conditions around the trailing edge of the airfoil and optimizing the shape of the edge did suppress the noise. The experts also found that asymmetrical serrations reduced the noise more than symmetrical serrations.&nbsp;



However, the extent of noise reduction varied with different operating conditions, so the scientists emphasized that the airfoil designs should be further evaluated based on the specific application for which they would be used.



For example, wind turbines have complex incoming flow environments that require a more general noise reduction technology. Examining noise reduction techniques under the influence of different incoming flows would make their conclusions more universal.



The researchers believe their work will serve as an important guide for airfoil design and noise control in the future.



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Owl wings inspire noise reduction in wind turbines and aircraft

The turning blades on wind turbines and drones make a...

Many birds learn their songs in the same way that humans learn a language or dialect –from their parents and neighbors, through mimicry. According to most biologists, this is an uncertain and error-prone method, often resulting in slow but unmistakable changes in the nature of <a href="https://www.earth.com/news/humpback-whale-songs-are-used-to-locate-not-attract-other-whales/">songs</a> over the years.



However, new research led by the <a href="https://www.berkeley.edu/">University of California, Berkeley</a> has found that some isolated populations of double-collared East African sunbirds have been singing the same songs - passed down to each new generation - for up to a million years.&nbsp;



The amazingly static nature of their songs may be due to the birds’ unchanging environment. The birds have inhabited so-called sky islands on East African mountaintops since ancient times.



"If you isolate humans, their dialects quite often change; you can tell after a while where somebody comes from. And song has been interpreted in that same way," said study senior author Rauri Bowie, a professor of Integrative Biology at UC Berkeley. "What our paper shows is that it's not necessarily the case for birds. Even in traits that should be very labile, such as song or plumage, you can have long periods of stasis."



According to Professor Bowie and his colleagues, the idea that birdsong changes very often likely arose from studies of Northern Hemisphere birds, which have repeatedly encountered environmental changes, such as glaciers coming and going over the last thousands of years. These changing environmental conditions can cause significant modifications in plumage, song, and mating strategies.



However, since mountaintop environments in the tropics, particularly in East Africa (such as Mount Kenya or Kilimanjaro) have witnessed very little geological change over the millennia, the birds living there faced no evolutionary pressure to change their plumage or songs.



"We are showing, using a really nice setup where we could look at song evolution using naturally isolated populations, that [in East African sunbirds] you don't see this gradual change through cultural or genetic drift at all," Bowie said. "You see these sharp bursts of change in a trait such a birdsong and lots and lots of evidence for stasis, even when that trait should be very plastic. To me, that was a really fascinating result."



The study is published in the journal <a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2021.2062">Proceedings of the Royal Society B</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The song of the East African sunbird may be a million years old

Many birds learn their songs in the same way that...

The Atlantic Forest of Brazil, Argentina and Paraguay is quite threatened, so it’s no surprise that lowland tapirs in this <a href="https://www.earth.com/news/deforestation-exposes-coastal-cities-to-more-deadly-storms/">forest</a> are severely endangered as well. Although tapirs are adaptable and found in a wide variety of habitats across South America, they are still declining in numbers across their range. Lowland tapirs are now found in only 1.78 percent of their original range in the Atlantic Forest.&nbsp;



A new study published in the journal <a href="https://neotropical.pensoft.net/">Neotropical Biology and Conservation</a> warns of the dire need for conservation actions to protect lowland tapirs of the Atlantic Forest. The research was headed up by Dr. Kevin Flesher of Biodiversity Study Center, Michelin Ecological Reserve and Dr. Patrícia Medici of the <a href="https://tapirconservation.org.br/">Lowland Tapir Conservation Initiative</a>.



"Of the 48 tapir populations identified during the study, between 31.3% and 68.8% are demographically unviable (low number of individuals), and between 70.8% and 93.8% of the populations are genetically unviable (low gene flow). Only 3-14 populations are still viable in the long run when both criteria are considered. The evidence suggests that with the appropriate conservation actions, the lowland tapir could be broadly distributed throughout the Atlantic Forest," explained Dr. Flesher.&nbsp;



"Tapirs have low reproductive potential, including a long reproductive cycle with the birth of just one young after a gestation period of 13-14 months and intervals of up to three years between births. Our populational simulations clearly show how, in the case of small populations, even the loss of a single individual per year can result in rapid extinction of an entire local population," added Dr. Medici.&nbsp;



Dr. Flesher spent 15 years visiting 93 reserves in the Atlantic Forest, conducting interviews and analyzing 217 data sets to create a conservation plan for tapirs in the area. Unfortunately, tapirs in the states of São Paulo and Paraná in Brazil - where the largest number of populations remain - are isolated from each other.



"As far as our knowledge goes, there is no evidence of movement of tapirs between these populations," said Dr. Medici.&nbsp;



The fragmented populations aren’t connecting with each other, not because of great distances but the threat from cars involved. "The central problem is the multiple threats they face while crossing the habitat," said Dr. Flesher.&nbsp;



Highways and attendant motor traffic are a huge obstacle and threat to disbursing tapirs. "For example, the heavy traffic on highway BR-101 (which cuts the Brazilian Atlantic Forest from North to South) is a death trap to wildlife. Tapirs often die when attempting to cross it," explained Dr. Medici.&nbsp;



Highway traffic is a significant cause of death for tapirs in six out of eight reservations where highways cross tapir populations. However, the situation seems to call for a small amount of optimism. "Despite these continuing challenges for tapir conservation, most populations appear to be stable or increasing and the conservation outlook for the species is better than several decades ago, when the first efforts to protect the species began," said Dr. Flesher.



---By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Lowland tapirs in the Atlantic Forest are at risk of extinction

The Atlantic Forest of Brazil, Argentina and Paraguay is quite...

Accidentally trapping marine animals such as sharks, seabirds, turtles, or sea mammals in fishing gear is one of the biggest barriers for making fisheries more sustainable. While <a href="https://marineprotectedareas.noaa.gov/">marine protected areas</a> are aiming to minimize accidental catch, they often prove to be quite inefficient in protecting marine biodiversity, particularly in the case of marine species that are very mobile and constantly travel between these static areas.&nbsp;



According to new research from the <a href="http://www.washington.edu/">University of Washington</a> (UW), “dynamic ocean management,” or the shifting of ocean closures, can be much more effective against accidental catch.



“We hope this study will add to the growing movement away from permanently closed areas to encourage more dynamic ocean management,” said study senior author&nbsp;Ray Hilborn, a professor at the UW <a href="https://fish.uw.edu/">School of Aquatic and Fishery Sciences</a>. “Also, by showing the relative ineffectiveness of static areas, we hope it will make conservation advocates aware that permanent closed areas are much less effective in reducing accidental catch than changes in fishing methods.”



Professor Hilborn and his colleagues investigated 15 fisheries around the world, and modelled what would happen both to targeted fish and accidental catches (or “bycatch”) if 30 percent of the fishing grounds were permanently closed, compared with dynamic management. They found that restricting fishing by 30 percent would only diminish bycatch by 16 percent, in contrast to using dynamic closures, which could reduce accidental catch by a staggering 57 percent.



“We found we can significantly reduce bycatch without decreasing the catch of target species by closing small fishing areas that can move year to year,” said study lead author&nbsp;Maite Pons, who completed this article as a UW postdoctoral fellow. “This dynamic approach is increasingly valuable as climate change drives species and fisheries into new habitats, altering these interactions.”



However, the authors acknowledge that, in some cases, static protected areas may remain the best choice. If the main purpose is to protect a critical habitat, a biodiversity hotspot, or a critical feature, static closures might remain most effective and easier to implement. Thus, all conservation goals should be broadly considered before determining which types of ocean protections are best in a specific situation.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Dynamic ocean closures offer protection from accidental catch

Accidentally trapping marine animals such as sharks, seabirds, turtles, or...

Go to any natural history museum, watch any dinosaur movie, and undoubtedly the big bad will be a <a href="https://www.earth.com/news/flesh-eating-theropods-were-extremely-fast/">theropod</a>. This terrifying, exceptionally toothy group includes Tyrannosaurus, Velociraptor, Allosaurus, and many others. Paleontologists are finally unraveling how the murderous jaws of these predatory dinosaurs evolved.



A new study, published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a> looked at the lower jaws of over 40 theropod dinosaur species. While the most well-known theropods are big and toothy, they also came in many shapes and sizes. Some were small, and some were, in fact, toothless.&nbsp;



By running the different jaws through computer modeling to test their strength, the researchers found that over the course of their evolution, theropod jaws grew progressively stronger. The predatory dinosaurs expanded the rear, or posterior, portion of their jaws (sideways or laterally), and the mechanical strength increased over the course of their over 100-million year history.&nbsp;



“Although theropod dinosaurs are always depicted as fearsome predators in popular culture, they are in fact very diverse in terms of diets. It is interesting to observe the jaws becoming structurally stronger over time, in both carnivores and herbivores. This gives them the capacity to exploit a wider range of food items," explained study lead author Dr. Fion Waisum Ma of the <a href="https://www.birmingham.ac.uk/index.aspx">University of Birmingham</a>.



"Theropod dinosaurs underwent extreme dietary changes during their evolutionary history of 165 million years. They started off as carnivores, later on evolved into more specialized carnivores, omnivores and herbivores. Studying how their feeding mechanics changed is key to understanding the dietary transitions in other vertebrate animals too.”



While it makes sense that the hypercarnivorous meat-eaters would increase their lower-jaw strength, the herbivorous lineages also developed stronger jaws.&nbsp;



“It is fascinating to see how theropod dinosaurs had evolved different strategies to increase jaw stability depending on their diet," said study co-author Dr. Stephan Lautenschlager. "This was achieved through bone remodeling – a mechanism where bone is deposited in regions of the jaw that experience high stresses during feeding.”&nbsp;



This evolutionary pattern is reflected in the ontogeny, or growth, of the individual animals. For example, juvenile tyrannosaurs possessed proportionally slimmer and downturned jaws compared to adult individuals.&nbsp;



“The similarity between jaw strengthening through growth and through time suggests that developmental patterns in juvenile dinosaurs ultimately affected the evolution of the whole group," concluded Dr. Lautenschlager&nbsp; "This likely facilitated the jaw evolution of theropod dinosaurs and their overall success for over 150 million years.”



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By <a href="http://mailto:rugerpaleo@gmail.com">Alex Ruger</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Jaws of predatory dinosaurs grew stronger as they evolved

Go to any natural history museum, watch any dinosaur movie,...

We live in a diverse world with different ecosystems and <a href="https://www.earth.com/news/shrinking-habitats-alien-species-threaten-native-trout/">habitats</a>. For centuries, scientists have been studying how flora and fauna interact within these natural communities. Some animals are creatures of habit who frequently eat in the same spots, travel on the same roads, and raise their young in the same places. The term "site fidelity" is used by ecologists to characterize the behavior of animals who are fixed in their routines and tend to return to a previously occupied location. 



The habit of many animals, from fish to birds to mammals and insects, to return to regularly frequented areas. Site fidelity is everywhere in nature, whether it's salmon returning to their native streams to breed or birds returning year after year to the same nest site.



According to a new study, while this "consistent" behavior may be beneficial when environmental conditions aren't changing rapidly, the benefits may not be realized in the ever-changing world dominated by humans. The research was focused on a literature review led by the <a href="http://www.uwyo.edu/">University of Wyoming</a>.



When animals get familiar with a location, site fidelity can help them figure out where to obtain good food or safe havens from predators, as well as how to get to and from these resources quickly. On the other hand, the research team discovered a new trend in the scientific literature.



“Animals that have strong site fidelity are having a tough time adjusting to the novel landscapes that are showing up around them as a result of humans,” said study co-lead author Professor Jerod Merkle.



The researchers pointed out that animals with strong site fidelity may not survive or reproduce as well as animals with more flexible behaviors when faced with human disturbances or climate change. When a population consists of a large number of site loyalists, a population decrease might occur due to the changes in the environment.



For instance, there are numerous mule deer winter ranges in Wyoming. With the addition of large natural gas fields, mule deer can make slight range adjustments to avoid infrastructure, but they stick to the same general area rather than abandoning it completely. The continued use of those damaged places may have detrimental implications. In one long-term study, researchers discovered a 40% drop in the mule deer population following large-scale energy development in their winter area.



Climate change also plays a major role in the adverse impacts on site-fidel animals. Under normal climate circumstances, site fidelity is a winning strategy for female northern elephant seals in the Pacific Ocean. In average years, site-faithful seals are better able to acquire food and gain fat compared to their more flexible cousins. But when aberrant climate events - such as extreme El Nios - induce major changes in the ocean ecology, behaviorally flexible seals win out. Female seals with strong site fidelity are unable to gain as much vital fat as they require to reproduce.



“Despite each of us working on very different species from one another, our group came together because we all recognized that there was a clear connection between strong site fidelity and species declines," said study co-lead author Briana Abrahms, an assistant professor at the University of Washington.



"We all thought it was important to call attention to this connection for other researchers and wildlife managers. Recognizing the types of species or behaviors that may suffer most from human-induced environmental change can help develop conservation priorities and actions."



While the analysis paints a bleak picture of the future for animals with high site fidelity, they also offer hope. The experts noted that occasionally, an animal will try something new and succeed. While such instances are uncommon, those "innovators" can be critical to a company's long-term survival in a changing environment.



"While these species appear to be stuck in their ways, many of them also have some unique but subtle ways of dealing with change,” said study co-author Jonathan Armstrong, an assistant professor at Oregon State University. “We just have to be patient and make sure populations don’t crash before such innovators come along,” Armstrong added.



The researchers offer a number of recommendations for researchers and practitioners towards the end of their paper. To begin, long-term monitoring is essential for determining how individuals and populations react to change. Second, they argue that biologists should not always expect animals to use and discover the optimal habitats. This is especially crucial when it comes to restoring new habitat regions, which may not work well for species with high site fidelity because they may not be able to "discover" these regenerated habitats.



As a result, the study authors propose that, rather than off-site mitigation, the conservation of species with high site fidelity should focus on the protection and restoration of highly frequented locations.



The study is published in the journal <a href="https://www.esa.org/frontiers-in-ecology-and-the-environment/">Frontiers in Ecology and the Environment</a>.



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By <a href="http://mailto:ashikha92@gmail.com">Ashikha Raoof</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Animals with strong site fidelity face an uncertain future

We live in a diverse world with different ecosystems and...

Osteoarthritis (OA) affects 45 percent of all cats, and over 90 percent of those older than 12. The condition is caused by the breakdown of cartilage cushion surrounding the joints, which makes the bones rub against each other, leading to chronic <a href="https://www.earth.com/news/why-does-our-breathing-rate-increase-when-we-feel-pain/">pain</a> and decreased joint movement.&nbsp;&nbsp;



The traditional medical treatments for cat arthritis consist of animal-specific nonsteroidal anti-inflammatory drugs (NSAID), similar to ibuprofen. These drugs can only be used safely for a short period of time, and cannot be given to cats suffering from kidney disease (which is another very common cat affliction).



However, a new drug manufactured by the company <a href="https://www.zoetis.com/index.aspx">Zoetis</a> has now been approved by the <a href="https://www.fda.gov/">U.S. Food and Drug Administration</a> (FDA). Solensia is a cat-specific monoclonal antibody that is injected by the veterinary under the skin once a month, and appears to be highly effective in diminishing the pains caused by OA and thus improving the animals’ mobility and overall quality of life. In two clinical trials, 77 percent of cat owners saw significant improvements in their pets after treatment with Solensia, compared to 67 percent in the placebo groups.



“Feline (arthritis) pain is typically undertreated because of a lack of effective solutions that are safe to use long-term, along with how difficult it can be for cat owners to administer oral medicines,” said Mike McFarland, chief medical officer at Zoetis. “The approval of Solensia is a significant step forward.”



“This is absolutely groundbreaking,” added Dr. Duncan Lascelles, a professor of Translational Pain Research and Surgery at the North Carolina State College of Veterinary Medicine. “I have been in pain research for 30 years and this is the most exciting development that has happened.”



“To be able to be mobile is so desperately important to the quality of life. Cats are described as needing 3D spaces. They need to move on the ground but they also need to be able to get to elevation.”&nbsp;



“Finally, for the first time ever in the U.S., there’s a highly efficacious treatment to manage joint pain in cats. And therefore extend their life, extend their happiness, and extend that beautiful relationship between cats and their owners,” Dr. Lascelles concluded. &nbsp;



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Revolutionary treatment greatly extends the lives and happiness of cats

Osteoarthritis (OA) affects 45 percent of all cats, and over...

New research led by a team of biologists from the <a href="https://www.utah.edu/">University of Utah</a> has found that California mice eat <a href="https://www.earth.com/news/how-predators-have-outsmarted-monarch-butterflies/">monarch butterflies</a> that fall to the ground. This is despite the fact that these butterflies possess a potent “chemical armor” from eating milkweed with toxic cardenolides. The milkweed toxins build up in their bodies and make monarchs unpalatable to most (but not all) predators.



Scientists have long observed that in Central Mexico, the place with the largest winter aggregations of monarchs, the black-eared mouse (Peromyscus melanotis) eats up to 40 of these butterflies each night. More recently, researchers found that the western harvest mouse (Reithrodontomys megalotis) also consume grounded monarchs at the Pismo State Beach Monarch Butterfly Grove in California.



To study mice-monarch interactions, the researchers first trapped rodents in the grove in February 2020 and screened their feces for monarch DNA, which they found in one sample. The scientists intended to return the next year, but unfortunately, after years of gradual decline, the monarch population finally crashed.



"At a site where 100,000 butterflies used to roost, in 2020 there where were fewer than 200 monarchs. So, we had to change tactics," said study lead author Sara Weinstein, a postdoctoral researcher at the University of Utah. "We tested whether rodents would feed on the butterflies using captive-reared monarchs."



Weinstein and her colleagues found that rodents that were offered monarchs ate them, usually favoring high-calorie parts with fewer toxins such as the abdomen or thorax. "Many rodent species are likely to have some resistance to cardenolides in monarchs, due to genetic changes at the site where these toxins bind," explained Dr. Weinstein.&nbsp;



"The Pismo Grove is one of hundreds of western monarch aggregation sites, and it seems likely that, at least in the past, rodents throughout the western monarch range may have supplemented their winter diets with monarchs. If you can handle the cardenolides in a monarch, their bodies are full of fat and offer a pretty good meal."



The massive decline of monarch populations is only one example of an ongoing “insect <a href="https://www.earth.com/news/the-sixth-mass-extinction-is-currently-in-progress/">apocalypse</a>.” According to Dr. Weinstein, about 40 percent of invertebrate species are currently threatened and over 70 percent of flying insect biomass may already be gone. “This is devastating on its own and is also going to have enormous impacts on the other organisms that feed on insects," Dr. Weinstein said.



"Western monarchs and other western butterflies need conservation attention and part of that awareness-raising is illuminating the many ways these animals are interconnected to other insects, birds, mammals, as well as our human communities. This study helps us appreciate more deeply how fewer butterflies means less food for other native animals," added Emma Pelton, a senior conservation biologist at the <a href="https://www.xerces.org/">Xerces Society for Invertebrate Conservation</a>.&nbsp;



The study is published in the journal <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3607">Ecology</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

California mice can feed on poisonous monarch butterflies

New research led by a team of biologists from the...

In a new study from the <a href="https://www.uc.edu/">University of Cincinnati</a>, researchers have discovered that a type of brightly colored jumping spider is <a href="https://www.earth.com/news/dinosaurs-may-have-had-pops-of-color-like-modern-ducks/">color</a> blind. The study was focused on Saitis barbipes, a common jumping spider found in Europe and North Africa. 



The males of this species have a furry red crown and legs. They are known for performing elaborate courtship dances.



“We assumed they were using color for communication. But we didn’t know if their visual system even allowed them to see those colors,” said study co-first author David Outomuro.



Using microspectrophotometry to examine jumping spiders collected in Slovenia, the team found no evidence of a red photoreceptor. The experts also looked for colored filters that might shift green sensitivity to red, but found that there were none.



The researchers ultimately determined that, most likely, bright red colors appear no different than black markings to these jumping spiders.



"To quantify and visualize whether females may nevertheless be capable of discriminating red from black color patches, we take multispectral images of males and calculate photoreceptor excitations and color contrasts between color patches," explained the study authors&nbsp;&nbsp;



"Red patches would be, at best, barely discriminable from black, and not discriminable from a low-luminance green."



“It’s a bit of a head-scratcher, what’s going on here,” said study co-author Professor Nathan Morehouse. “We haven’t solved the mystery of what the red is doing.”&nbsp;



Even though animals use color in all sorts of ways, including camouflage, it’s not always apparent what bright colors might signify, according to Professor Morehouse. “We spent a lot of time talking about it as a group. What else could it be? I feel there’s an interesting story behind the mystery."



Study senior author Cynthia Tedore, a research associate at the University of Hamburg, said the results of the research were surprising.



“Males have bold red and black coloration on their forward-facing body surfaces which they display during their courtship dances; whereas, females lack red coloration altogether. This initially suggested to us that the red color must play some role in mate attraction," said Tedore.



“Instead, we found that red and black are perceived equivalently, or nearly so, by these spiders and that if red is perceived as different from black, it is perceived as a dark ‘spider green’ rather than red."



The researchers believe that the spider’s red and black colors may possibly improve defensive camouflage.



“For predators with red vision, at natural viewing distances, the spider's red and black color patches should blur together to become an intermediate orangish-brownish color, which would help the spider blend in with its leaf litter habitat better than all-black coloration would,” said Tedore.



The experts noted that there are many colorful jumping spiders that see red perfectly well. There are also many dull-colored spiders that have great color vision.



The study is published in the journal <a href="https://www.springer.com/journal/114">The Science of Nature</a>.



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Scientists find a colorful jumping spider that is color blind

In a new study from the University of Cincinnati, researchers...

A new study from <a href="https://www.anu.edu.au/">Australian National University</a> (ANU) creates a stark choice: step up conservation efforts or lose the regent honeyeater, a beautiful <a href="https://www.earth.com/news/songbirds-and-humans-use-similar-speech-patterns/">songbird</a>, within 20 years. The new study reveals that even the current intensive conservation efforts aren’t enough.



“The regent honeyeater population has been decimated by the loss of over 90 per cent of their preferred woodland habitats,” said study lead author Professor Rob Heinsohn.



"Less than 80 years ago, it was one of the most commonly encountered species, ranging from Adelaide to Rockhampton. Now it is on track to follow the dodo into extinction.”



There are currently less than 300 regent honeyeaters left, making it one of Australia’s rarest birds. Habitat destruction forces the remaining honeyeaters to compete with larger birds for less habitat.



In 2015 the ANU researchers began an intensive research project focused on gaining greater understanding of the regent honeyeater’s decline. After years of field work, the scientists discovered that the decline in nest success was due to predation by other bird species and possums.&nbsp;



In the new research, the scientists used their hard won field data to create a population model that predicts the bird’s future population.&nbsp;



“Our models show that current conservation efforts have provided essential life support for the regent honeyeaters, but do not go far enough," said study co-author Dr. Ross Crates. “We were able to isolate the three key conservation priorities necessary to secure the birds’ future."&nbsp;



The first conservation priority the research lays out is a doubling of nest success rates in both wild and zoo bred animals, facilitated by protecting the nests from predators.&nbsp;



Next captive breeding efforts releasing birds into the Blue Mountains must increase and remain steady for twenty years in addition to nest protection.&nbsp;



Lastly, the research emphasizes that the regent honeyeater can only survive into the future if more habitat is preserved and restored.&nbsp;



“Without more habitat, reintroductions and nest protection efforts will be futile, because the flock sizes will never reach the critical mass needed for the birds to breed safely without our protection," said Professor Heinsohn.&nbsp;&nbsp;



"Our study provides both hope and a dire warning - we can save these birds, but it will take a lot of effort and resources over a long time to pull it off.”&nbsp;



The study is published in the journal <a href="https://www.journals.elsevier.com/biological-conservation">Biological Conservation</a>.



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By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

How can we save the regent honeyeater from extinction?

A new study from Australian National University (ANU) creates a...

According to current scientific knowledge, the history of life on Earth was marked until now by five mass <a href="https://www.earth.com/news/volcanic-fertilization-led-to-severe-mass-extinction-event/">extinctions</a>, which were caused by natural phenomena and resulted in great global losses of biodiversity. In a new study, a group of biologists from <a href="https://manoa.hawaii.edu/">University of Hawai‘i at Mānoa</a> and the <a href="https://www.mnhn.fr/en">National Museum of Natural History</a> in Paris, France, argue that we are currently experiencing a Sixth Mass Extinction which, in contrast to the previous ones, is caused entirely by human activities.



By extrapolating from estimates obtained through the analysis of snail and slug populations, the scientists have shown that, since 1500, the Earth could have lost between 7.5 percent and 13 percent of the approximately two million of known species, thus between 150,000 to 260,000 species.



“Drastically increased rates of species extinctions and declining abundances of many animal and plant populations are well documented, yet some deny that these phenomena amount to mass extinction,” said&nbsp;study lead author Robert Cowie, a research professor of Biosciences at the University of Hawai’i.



“This denial is based on a biased view of the crisis which focuses on mammals and birds and ignores invertebrates, which of course constitute the great majority of biodiversity. Including invertebrates was key to confirming that we are indeed witnessing the onset of the Sixth Mass Extinction in Earth’s history.”



According to Professor Cowie and his colleagues, the situation is not the same everywhere on Earth. Although increasingly more marine species are threatened, the crisis affecting the seas and oceans is not so severe as that impacting the land. Moreover, on land, island species are more affected than continental ones, and a much larger number of terrestrial animals are endangered in comparison to plants.



Unfortunately, this ongoing extinction is denied by most of the people, including key political actors and policy-makers, and while conservation initiatives have been successful for certain charismatic animals, they cannot target all endangered species and reverse the overall thread of extinction.



“Despite the rhetoric about the gravity of the crisis, and although remedial solutions exist and are brought to the attention of decision-makers, it is clear that political will is lacking,” said Professor Cowie. “Denying the crisis, accepting it without reacting, or even encouraging it constitutes an abrogation of humanity’s common responsibility and paves the way for Earth to continue on its sad trajectory towards a Sixth Mass Extinction.”



The study is published in the journal <a href="https://onlinelibrary.wiley.com/doi/10.1111/brv.12816">Biological Reviews</a>.&nbsp;&nbsp;&nbsp;



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The Sixth Mass Extinction is currently in progress

According to current scientific knowledge, the history of life on...

Mammals have a pharynx, or throat, that starts at the back of the nose and ends below the back of the mouth. Although the pharynx is a single tube, it leads into two separate tubes - the windpipe, through which air reaches the lungs, and the esophagus, through which food reaches the <a href="https://www.earth.com/news/lizard-preserved-stomach-microraptor/">stomach</a>. The separation of the respiratory and digestive tracts at the base of the pharynx is critical for survival; air must be directed from the pharynx into the lungs, but food must be directed towards the stomach and must not enter the lungs.



This anatomical arrangement presents problems for mammals, who must avoid inhaling their food when they try to swallow it. This is the cause of choking and can be fatal. The situation is even more complicated for baleen whales, which feed while underwater. They open their mouths wide and lunge through a shoal of fish or small invertebrates, taking in numerous small prey items along with thousands of liters of water that must not flow into the windpipe.



Researchers at the <a href="https://www.ubc.ca/">University of British Colombia</a> in Vancouver have recently published a study that shows how baleen whales, also known as rorquals, achieve the separation of respiratory and digestive tracts while their mouths experience these extreme physical forces. They identified an anatomical mechanism that protects the whale’s airway as tons of water gushes into its mouth - they term this bulbous region of the soft palate the “oral plug.”



“We discovered a structure in fin whales, which likely exists in all lunge-feeding whales, or rorquals,” said Kelsey Gil of the UBC Zoology Department. “We’ve termed it the ‘oral plug’ and found that it blocks the channel between mouth and pharynx. It means that when a whale lunges, the entrance to the pharynx and thus the respiratory tract is protected.”



Although the mechanics of lunge feeding by whales was well understood, not much was known about how prey such as krill are manipulated and swallowed after a lunge. In addition, the general anatomy of the larynx was also well known. This is a hollow organ in the upper airway that is also the location of the vocal cords and has been investigated in connection with whale vocalizations. However, not much was known about the structure of the rest of the pharynx, the critical junction between respiratory and digestive tracts.&nbsp;



“It’s impossible to study this in a living whale, so we rely on tissue from deceased whales and use functional morphology to assess the relationship between a structure and its function,” said Gil.&nbsp;



By examining and dissecting adult and fetal fin whales, the researchers found that a musculo-fatty structure, the oral plug, seals the back of the mouth and pharynx when the whales feed. They manipulated the various structures to see how they could move. They also looked at the direction of muscle fibers to understand how they would move when muscles contracted and shortened.



“The oral plug is a part of the soft palate, so simply considering the gross anatomy, there is only one direction it should move,” explained Gil. “When the oral plug moves backward and upward to block the nasal cavities, it means that no other structure can be in that same spot below the nasal cavities. This forced us to then examine the larynx, since that spot is where we would expect to see the larynx during breathing, but it cannot be in that position during swallowing.”



During swallowing, the oral plug is lifted and this allows food to pass from the mouth into the pharynx. At the same time, the lifted plug protects the upper airways from food entry. The larynx is positioned at the floor of the pharynx, where laryngeal cartilages close to protect it. A muscular sac attached to the bottom of the larynx is forced upwards into the laryngeal cavity to completely block the lower respiratory tract.



The findings, published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>, also show that the pharynx in fin whales - and likely all rorquals - can only be used by either the respiratory or the digestive tract at any one time. This protects the animals from choking while feeding.&nbsp;



According to the researchers, no structure like the oral plug has been reported in any other animals. “There are very few animals with lungs that feed by engulfing prey and water, so the oral plug is likely a protective structure specific to rorquals that is necessary to enable lunge feeding,” said Gil.



The study authors conclude that these adaptations to facilitate swallowing in lunge-feeding whales were a critical development in the evolution of large body size. The largest animal species ever to have lived is thought to be the blue whale, which feeds in precisely this way.



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

"Oral plug" prevents whales from drowning while they eat

Mammals have a pharynx, or throat, that starts at the...

species in Callochitonidae