Pisinna kis

All <a href="https://www.earth.com/news/wild-animals-can-evolve-faster-than-previously-thought/">animals</a> need survival skills, and one critical skill for mice is finding the quickest route to safety. Researchers at the <a href="https://www.sainsburywellcome.org/web/">Sainsbury Wellcome Centre</a> at UCL wanted to know how mice decide on the best route to safety when they are in a new environment.



Study co-author Tiago Branco explained why this experiment differs from previous studies. “In many neuroscience studies, mice are trained to solve complex mazes and are given lots of time to learn how to do so. But in nature, mice do not have that luxury – when faced with threat, they must escape to shelter as quickly as possible. The question is how do mice learn this very quickly, without the opportunity of trial and error.”&nbsp;



To answer this question, the neuroscientists presented two or three routes back to a shelter and exposed mice to simulated threats. Then they blocked the most direct route and watched to see which path the animals would choose. The experts found that the mice preferred the shortest way to shelter.



Next, the team analyzed the inexperienced mice encountering a threat for the first time. Surprisingly, the researchers discovered that these individuals preferred the shortest route after exploring their surroundings for only 10 minutes.&nbsp;&nbsp;



“Mice are predated on by many species and so for a mouse it’s very important to know how to escape to safety," explained Branco. "If you put a mouse in a new environment, its priority is to map out space and figure out how to get to a safe place. This is in the natural repertoire of the mouse’s behavior and does not have to be explicitly instructed.”



The experts ascertained that mice can discover the shortest route by exploring their environment and assuming the best path to safety. This Is known as an innate heuristic, meaning that mice have evolved neural circuits that facilitate making intrinsic choices after exploring their environment.



“Animals are very good at learning about the things that matter to them," explained Branco. "To understand the mouse brain and the algorithms and neural circuits that support learning, it is important to look at the behaviours that the mouse has evolved to do and the constraints that they are under to learn fast and efficiently.”



The researchers look forward to exploring other questions about how animals make choices based on expectations. They also believe their findings will prove useful in the area of rapid learning research.&nbsp;



The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.



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By <a href="mailto:nire518@gmail.com">Erin Moody </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Mice make it a priority to find the best escape route

All animals need survival skills, and one critical skill for...

Coral reefs have complex soundscapes – created by fish and other creatures living there - which can be used by scientists to measure <a href="https://www.earth.com/news/diversity-abundance-coral-reef-health/">coral health</a>. However, traditional acoustic surveys of reefs rely on labor-intensive methods which face significant difficulties in assessing reef health through the use of individual recordings.&nbsp;



Now, a research team led by the <a href="https://www.exeter.ac.uk/">University of Exeter</a> has trained a computer algorithm using multiple recordings of both healthy and degraded reefs, allowing the machine to learn the difference. When fed new data, this algorithm was able to successfully identify reef health 92 percent of the time. &nbsp;&nbsp;&nbsp;



“Coral reefs are facing multiple threats including climate change, so monitoring their health and the success of conservation projects is vital,” said study lead author Ben Williams, a doctoral student in Soundscape Ecology at the University of Exeter. “One major difficulty is that visual and acoustic surveys of reefs usually rely on labor-intensive methods. Visual surveys are also limited by the fact that many reef creatures conceal themselves, or are active at night, while the complexity of reef sounds has made it difficult to identify reef health using individual recordings.”



The scientists’ approach to this problem was to use machine learning in order to train computers to learn “the song of the reef.” Their findings suggest that computers can pick up patterns that are undetectable to the human ear, which they can use to faster and more accurately assess reef health. While the meaning of many individual calls of reef inhabitants remains unknown, this new method can nevertheless distinguish between the overall sounds of healthy and unhealthy reefs.



“This is a really exciting development,” said study co-author Timothy Lamont, a marine biologist at <a href="https://www.lancaster.ac.uk/">Lancaster University</a>. “Sound recorders and AI could be used around the world to monitor the health of reefs, and discover whether attempts to protect and restore them are working.”



“In many cases it’s easier and cheaper to deploy an underwater hydrophone on a reef and leave it there than to have expert divers visiting the reef repeatedly to survey it – especially in remote locations,” he concluded.



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S1470160X22004575?via%3Dihub">Ecological Indicators</a>.&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

Coral reef health can be measured through sound

Coral reefs have complex soundscapes – created by fish and...

A new study led by the <a href="https://en.uniss.it/">University of Sassari</a> (UNISS) in Italy has found that <a href="https://www.earth.com/news/bottlenose-dolphins-struggle-with-weight-in-their-40s/">bottlenose dolphins</a>’ signature whistles, which they use to identify one another, are strongly influenced by where they live, and by the size of their local population. 



Although these whistles are unique to each individual animal, the experts discovered that their acoustic features are structured to a certain degree by dolphins’ local habitats and communities – a phenomenon similar to the development of regional accents in humans.



&nbsp;“Even if the bottlenose dolphin is among the most studied species of Cetacean, many aspects of their ecology and behavior are still unknown,” said study lead author Gabriella La Manna, a marine biologist at UNISS.&nbsp;



“Given how quickly human activities are changing the oceans, it is important to understand the environmental and socio-behavioral factors that allow animals to adapt to their environment.”&nbsp;



The scientists investigated the whistling habits of common bottlenose dolphins (Tursiops truncatus) in six geographically distinct populations in the Mediterranean Sea. By analyzing 188 hours of recorded sounds, they mapped variations in acoustic features such as duration and changes in pitch, and identified 168 signature whistles. The analysis revealed that the local ocean environment and population size had a significant effect on the whistles’ acoustic features.



For instance, signature whistles in areas with sea grass, such as Port Cros or Lampedusa, were higher pitched and shorter in length compared to those of dolphins living in areas with muddy sea floors. Moreover, among small dolphin populations like those from the Gulf of Corinth, the whistles had more changes in pitch than among larger populations. These findings suggest that bottlenose dolphins develop signature whistles that are best suited to their local habitats (the so-called “acoustic adaptation hypothesis”).



“I would like people to reflect on the importance of the acoustic environment in which dolphins live for the development and maintenance of their communication,” said Dr. La Manna.&nbsp;“Human activities, such as commercial shipping and nautical traffic, can severely affect this fundamental aspect of dolphins’ life.”



Further research is needed to clarify why certain environmental features influence in specific ways dolphins’ signature whistles, and to assess what impact anthropogenic factors have on these animals’ behavior and social communication.



The study is published in the journal <a href="https://www.nature.com/articles/s41598-022-10920-7#Sec2">Nature Scientific Reports</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

Dolphins have "accents" that vary by region

A new study led by the University of Sassari (UNISS)...

Social power among animal species has usually been characterized as being either male or female dominated. However, a new study published in the journal <a href="http://dx.doi.org/10.1016/j.tree.2022.04.004">Trends in Ecology &amp; Evolution</a> argues that such a binary understanding of <a href="https://www.earth.com/news/inequality-among-animals-can-shed-light-on-social-evolution/">inequality</a> in the degree of control or power that members of one sex exert over members of the other sex is too simplistic, failing to properly characterize the complex distribution of power between sexes.&nbsp;



The experts propose a new framework for assessing dominance, which places each species on a continuum, ranging from strict male to strict female dominance.&nbsp;



“Progress in this area has long been hampered by a binary vision of power asymmetries between the sexes, where most species were dominated by males and female dominance was anecdotal. This simplistic view has been reinforced by stereotypes that researchers carry because of the society in which they live and then unconsciously project onto the animals they're studying," explained study senior author Elise Huchard, a behavioral ecologist at the <a href="https://isem-evolution.fr/en/">Institute of Evolutionary Science of Montpellier</a> (ISEM).



According to Dr. Huchard, the distribution of power between the sexes has not been properly quantified in previous studies. By providing a comprehensive definition of intersexual power, together with a framework to measure it across various animal species, the researchers argued that each species could be placed on a continuum from strict male dominance to strict female dominance, so that hypotheses regarding how females or males can empower themselves can be better assessed.



While for males, the path to power seems rather simple and straightforward, involving physical dominance and coercion, for females the methods of establishing social power are more diverse, involving physiological, morphological, behavioral, and socio-ecological routes.&nbsp;



In the case of species where females are dominant, such as bonobos, hyenas, or lemurs, reproductive control (control over when and with which partners to mate) appears to be the main strategy for securing power. This comes in the form of resistance to mating, promiscuity, or even, in the case of hyenas, the evolution of genitals designed specifically for females to control fertilization.



“We hope that this framework will be used to quantify intersexual power in reproductive and social contexts and to facilitate the study and comparison of intersexual power relationships across mammalian societies, perhaps even including humans,” the authors 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

Power between the sexes has not been properly quantified

Social power among animal species has usually been characterized as...

Strong friendships between males aren’t very common in the animal kingdom. Instead, males typically compete among themselves for access to females. In some special circumstances though, male friendships can help with <a href="https://www.earth.com/news/gut-molecule-makes-animals-switch-from-eating-to-mating/">mating</a> success. In fact, some manakins depend on males working together to attract females with elaborate cooperative mating displays.&nbsp;



Among other animals, such as baboons, male friends can help each other rise in social status or defend females from another male, which promotes mating success.&nbsp;



Now, researchers from the <a href="https://www.dpz.eu/en/home.html">German Primate Center (DPZ) Leibniz Institute for Primate Research</a> looked into the benefits of male friendships among wild Guinea baboons in Senegal. These baboons are known for strong male social bonds but lack of a clear male hierarchy.



Among these baboons, the core social groups are made of one male with one to six females and their offspring, with the male typically fathering all of the offspring. The females choose a male freely and stay with him for a few weeks to several years. There are also bachelor males who are not usually sexually active. Several of these core groups along with bachelor males make up a “gang” of baboons.&nbsp;&nbsp;



The scientists wanted to know if male baboons with more friends attracted more females due to the possibility of greater levels of protection for the females and their offspring. Contrary to the hypothesis, males with more friends were not more attractive.&nbsp;



The study revealed that males also spent less time with their male friends once they started spending time with a female and especially when they fathered offspring. Males still maintained some friendships, but just adjusted the amount of time they spent with those friends.&nbsp;



To carry out the research, Federica Dal Pesco and her colleagues collected four years of field data. The experts observed the behavior of 30 males and determined paternity of 50 young.&nbsp;



"Contrary to our predictions, we found no evidence that male-male sociality was linked to higher reproductive success. Instead, we observed a strong negative relationship between bond strength and male reproductive success (i.e. number of associated females and paternities)," explained the study authors. "Guinea baboon males that were associated with a higher number of females spent less time affiliating with other males.&nbsp;



"While a number of now classic studies reported a positive relationship between sociality and reproductive success in both males and females across several mammalian and bird species, our results indicate that male-male sociality need not directly translate into increased short-term reproductive success. Instead, males that invest time and energy in relationships with females, at the expense of relationships with males, have the highest reproductive success."



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



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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

Male baboons invest more time in relationships with females

Strong friendships between males aren’t very common in the animal...

<a href="https://www.earth.com/news/hummingbirds-cannot-maintain-an-energetic-lifestyle-at-high-altitudes/">Birds</a> that hunt their prey during the night need special adaptations in order to allow them to see in low light conditions and to judge the distance to obstacles in their flight path as well as the distance to their prey. Although these adaptations have been relatively well studied in nocturnal birds such as owls and nightjars, they have not been investigated in the world’s only nocturnal hawk, the letter-winged kite (Elanus scriptus).



Although some species of hawks (Accipitriformes) and falcons (Falconiformes) can hunt at dusk, the letter-winged kite is the only species that is primarily active at dusk and at night. It inhabits the arid central regions of Australia, avoiding settled areas and towns. This habitat preference, along with the species’ nocturnal activity pattern and nomadic movements, makes&nbsp;E. scriptus&nbsp;rather difficult to observe in the wild.



In the past, there has been speculation that the species is more like an owl than a hawk because it appears to have unusually large eyes that face forwards. Some have suggested that the soft tissues of the eyes resemble those of nocturnal birds more than diurnal species, including the other Australian Elanus species, the black-shouldered kite (Elanus axillaris).&nbsp;



Birds that hunt their prey during the night often show specialized adaptations to their visual systems and skeletons. These anatomical changes include large orbits to accommodate eyes with large retinas that contain many photoreceptors. The eye of a nocturnal raptor also usually has a relatively small optic foramen, the hole in the skull through which the optic nerve travels to the brain. Certain areas of the brain of a nocturnal raptor may also be enlarged to facilitate detailed processing and interpretation of the images received by the eyes.



An international study led by <a href="https://www.flinders.edu.au/">Flinders University</a> has now tested the speculation about the letter-winged kite’s adaptations using computed tomography (CT) scanning techniques to obtain high-resolution images from three specimens, along with 27 other raptor skulls. The skulls, all of which were sourced from museums within Australia, came from 16 raptor species in total, 12 of which belong to the Accipitriformes (hawks, eagles and kites) and the remaining three to the Falconiformes (falcons). The images were used to measure and compare eye socket characteristics, such as the orbit diameter and the optic foramen diameter.&nbsp;



“Letter-winged kites hunt at night and must be able to navigate obstacles in the dark while tracking down their favorite prey, the long-tailed rat,” said Professor Vera Weisbecker. “It has therefore long been speculated that their visual system shows adaptations for seeing in the dark, and particularly that they are similar to owls in having larger eyes than other hawks, and larger image processing centers in the brain.”



Dr. Karine Mardon is an experts in The National Imaging Facility at the University of Queensland Centre for Advanced Imaging. Dr. Mardon scanned the skulls of the birds of prey included in the study, and the researchers then compared 3D reconstructions of the letter-winged kite skulls and brains with those of the other birds of prey.



The results of the analysis revealed that things are not as clear as night and day. There was no difference in the relationship between the orbit and optic foramen diameters for the nocturnal&nbsp;letter-winged kite and its diurnal congeners, the black-winged kite (Elanus caeruleus) and the black-shouldered kite (Elanus axillaris). Elanine kites, as a whole, seem to have relatively large orbit diameters, but relatively small optic foramina compared to other species.



“Contrary to many anecdotal reports, the dimensions of the eye of letter-winged kites were no different to two closely related kites from the same genus – the black-shouldered and the black-winged kites,” said study lead author Aubrey Keirnan, a PhD student in Dr. Weisbecker's lab.



“But there was a twist in the story: we realized that all three kite species had larger orbits relative to their optic foramen, the hole in the back of orbit that the optic nerve passes through. This is often seen in nocturnal birds, where a small number of nerves relay a lot of input from the eye into a high-contrast, low-resolution image.”



“This suggests all&nbsp;Elanus&nbsp;kites may be pretty good at seeing in the dark and not too good at seeing in daylight – but for some reason, only the letter-winged kite has made the move into a nocturnal lifestyle."



According to Dr Weisbecker, this might also explain many reports that the letter-winged kite is particularly active during moonlit nights: “It might not actually be very good at flying in the total dark, unlike many owls.”



The study was co-led by Dr. Andrew Iwaniuk from the University of Lethbridge in Canada. He noted that the use of anatomical observations to infer the species’ behavior was an innovative approach to understanding a bird that is notoriously difficult to observe in the wild.



“The species lives in remote, arid Australia, avoids human settlements and is highly elusive. Population estimates vary between 670 and 6,700 individuals according to the IUCN, and it is currently listed as near-threatened. To conserve the species, it is critical that we understand its behavioral needs and capabilities, but they are extremely difficult to observe," said Dr. Iwaniuk.



“We are extremely lucky to have Australia’s amazing museum collections at our disposal to help us understand this bird without the need to find and disturb the species. For example, the letter-winged kite, and its relatives, might be impacted differently by artificial light sources than other hawks."



Dr. Jeroen Smaers of Stony Brook University said the research perfectly exemplifies how studying variation across many species enlightens our understanding of individual species - an approach that is starting to show its contributions to animal conservation.



“Our work on the letter-winged kite is really just the beginning," said Keirnan. "Our measurements showed that many other birds of prey are quite unique in one aspect or other of their visual system. I am excited to spend my PhD on delving further into how measurement of the visual system can help in the understanding and management of other birds.”



The study is published in the journal <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.220135">Royal Society Open Science</a>.



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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

The world’s only nocturnal hawk may not see well in the dark

Birds that hunt their prey during the night need special...

Tree hyraxes are non-descript, mid-sized <a href="https://www.earth.com/news/mammals-change-their-schedules-to-adapt-to-city-life/">mammals</a> that wake after dark in the canopies of Tropical African forests. Because they’re a shy nocturnal mammal living high in trees, little has been discovered about their behavior.&nbsp;



Now, experts at the <a href="https://www.helsinki.fi/en">University of Helsinki</a> are using new techniques to try and understand tree hyrax behavior in the Taita Hills of Kenya.&nbsp;



"Many aspects of tree hyrax ecology remain very poorly known. They are known to mainly feed on leaves of woody plants," wrote the study authors.&nbsp; "Tree hyraxes thus depend on trees for food, but they also utilize den trees for shelter, and dense canopy also allows easy movement between trees."&nbsp;



"Tree hyraxes are thought to be mainly solitary animals that maintain social relationships by calling and scent-marking signals. They are highly vocal and calling seems to be their primary means of communication."



Using thermal imaging cameras, the researchers were able to observe hyrax social behavior - something never before seen. The study also revealed what plants they especially enjoyed eating and where they hid for shelter.



In addition to thermal imaging cameras, automated acoustic recorders captured hyrax vocalizations. Besides being able to record data on interactions between the animals, these recordings allowed scientists to estimate a population for the first time.&nbsp;&nbsp;&nbsp;



“In small forest patches, the calls of tree hyraxes were rarely heard, and only in the early hours of the morning. These few surviving animals are making every effort to avoid detection and the attention of potential poachers,” said Hanna Rosti, who has long studied tree hyraxes.



Armed with their new data, the scientists estimate that there are only 2,000 to 4,000 hyraxes in the Taita Hills area where they conducted their research. This information is important for conservation of the hyrax. The scientists hope that the study will also have positive implications for tree hyraxes throughout Africa.&nbsp;&nbsp;&nbsp;



“The results acquired through this research will move tree hyrax conservation significantly forward, not only in Taita Hills but also in other parts of Africa," said Professor Jouko Rikkinen.



"The methods used can also be applied to other nocturnal animals that are difficult to get close to."



The study is published in the journal <a href="https://www.nature.com/srep/">Scientific Reports</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 clues about the secretive lives of tree hyraxes

Tree hyraxes are non-descript, mid-sized mammals that wake after dark...

Pisinna kis

Taxonomic tree: