<a href="https://www.earth.com/news/sex-impacts-gene-expression/" target="_blank" rel="noreferrer noopener">Sexual dimorphism</a>, which is the observable difference in appearance between male and female members of a species, occurs widely across the animal kingdom, including in humans. An interesting variation of this is sex-limited polymorphism, where one sex exhibits more variation in a certain trait compared to the other. 



An international team of scientists has explored this concept by examining the genetic basis for color polymorphism in adult female <a href="https://www.earth.com/news/cuckoos-are-unable-to-change-their-migrations-in-response-to-climate-change/" target="_blank" rel="noreferrer noopener">cuckoos</a> of the genus Cuculus, which are known for their brood parasitic behavior. The research provides insights into the evolutionary development and practical implications of this trait variation.



<h2 class="wp-block-heading" id="h-genetic-basis-of-female-cuckoo-colors">Genetic basis of female cuckoo colors</h2>



The scientists examined why adult female cuckoos, unlike their uniformly gray male counterparts, may exhibit either gray or rufous (reddish-brown) plumage. This variability is not only evident across different cuckoo species but also within populations of the same species.



Using genome-wide association analysis on nuclear DNA from both Common and Oriental cuckoos, the researchers aimed to pinpoint the genetic factors behind the females' diverse plumage in an attempt to understand the underlying pigmentation mechanisms and the evolutionary history of these <a href="https://www.earth.com/news/scientists-wonder-evolutionary-success/" target="_blank" rel="noreferrer noopener">traits</a>.



In <a href="https://www.earth.com/news/untold-story-of-bird-evolution-revealed-through-genetics/" target="_blank" rel="noreferrer noopener">birds</a>, unlike in mammals, it is the females that are heterogametic (ZW), differing from the homogametic males (ZZ). This led researchers to speculate that the observed color variation in female cuckoos might be linked to genes on the W chromosome. 



“We found that, instead of a single gene or set of genes, nearly all variations in the gray or rufous coloration were associated with the full length of the female-limited W chromosome,” said co-author Mark Haber, the executive director of the <a href="https://asrc.gc.cuny.edu/" target="_blank" rel="noreferrer noopener">CUNY Advanced Science Research Center</a> (CUNY ASRC) and a psychology professor at the <a href="https://www.gc.cuny.edu/" target="_blank" rel="noreferrer noopener">CUNY Graduate Center</a>.



<h2 class="wp-block-heading" id="h-biochemical-processes-of-cuckoo-colors">Biochemical processes of cuckoo colors</h2>



The scientists also examined the biochemical processes of coloration, revealing that both the Common and Oriental cuckoos use two forms of melanin-based pigmentation - similar to that in human skin - to produce their <a href="https://www.earth.com/news/for-songbirds-bright-colors-are-a-blessing-and-a-curse/" target="_blank" rel="noreferrer noopener">color</a> variations. 



Further genomic analysis of these species traced the origin of the color polymorphism in female cuckoos to a mutation that occurred over one million years ago, long before these species diverged around 140,000 years ago.



<h2 class="wp-block-heading" id="h-potential-advantages-of-female-cuckoo-coloration-nbsp">Potential advantages of female cuckoo coloration&nbsp;</h2>



The implications of these color variations are profound. For instance, female cuckoos with the rarer rufous plumage might benefit from mimicking juvenile cuckoos to avoid male harassment during mating seasons.&nbsp;



Moreover, as brood parasites who lay their eggs in the nests of other bird species, rufous females could potentially escape detection by host species better than their gray counterparts, which might reduce the risk of being attacked by host parents.



“The fascinating idea that many other sex-specific traits, which are harder to study, might also be genetically determined in the matrilinear genome, similar to the color polymorphism in female cuckoos,” concluded senior author Jochen Wolf, an expert in evolutionary biology at LMU Munich.



<h2 class="wp-block-heading" id="h-more-about-cuckoo-birds">More about cuckoo birds</h2>



Cuckoo birds are known for their distinctive calls and unique breeding behavior, particularly their practice of brood parasitism. This involves laying their eggs in the nests of other bird species, leaving the unsuspecting host birds to raise the cuckoo's offspring.&nbsp;



As a result, the host species may inadvertently neglect their own young due to the demanding nature of the cuckoo chick, which often grows larger than its foster siblings.



Cuckoos are found across the world and are highly adaptable to various environments. The family Cuculidae, to which they belong, includes both brood-parasitic cuckoos as well as species that raise their own young. Their diet varies from insects to caterpillars, and some species also consume fruits and seeds.



The cuckoo's call, which gives them their name, is emblematic in culture and often signals the arrival of spring. The most commonly recognized call is that of the common cuckoo in Europe, famously captured in the phrase "cuck-oo." 



This sound has not only embedded them in folklore but also inspired the creation of the cuckoo clock, where the bird's call marks the passing hours.



The study is published in the journal <a href="http://dx.doi.org/10.1126/sciadv.adl5255" target="_blank" rel="noreferrer noopener">Science Advances</a>.



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Female cuckoo colors provide evolutionary advantages

Sexual dimorphism, which is the observable difference in appearance between male and female members of a species, occurs widely across the animal kingdom, including in humans. An interesting variation of this is sex-limited polymorphism, where one sex exhibits more variation in a certain trait compared to the other.  An international team of scientists has explored this concept by examining the genetic basis for color polymorphism in adult female cuckoos of the genus Cuculus, which are known for their brood parasitic behavior. The research provides insights into the...

An international research team led by the <a href="https://www.umass.edu/">University of Massachusetts Amherst</a> has conducted the first global assessment of the impacts to native species by <a href="http://www.earth.com/news/invasive-rusty-crayfish-demise/">invasive species</a>. The experts wanted to measure the extent of the damage as invaders become more widespread and abundant. 

“What surprised me most was the magnitude of some of these effects,” said study lead author and invasion ecologist Professor Bethany Bradley. “Invasive animal pests, like Emerald Ash Borer or lionfish, cause nearly a 50 percent decline in native populations. That's the average case - on average, invasive pests will cut the populations of native species in half if we don't prevent or control those invasions.”

According to Professor Bradley, as alien garlic mustard invades forest understory in New England, the number of native sugar maple seedlings declines. Across the region’s wetlands, invasive purple loosestrife is linked to declines in native red-winged blackbirds and song sparrows.

“Our principal finding is that if the invasive species is at a higher trophic level, that is, they are likely eating the native species, then just a few invasive individuals can cause a sharp decline in native populations,” said Professor Bradley. “Once those invaders reach higher abundance, the damage has long ago been done. This has big implications for management. Early detection becomes critical.”

The investigation was based on the analysis of 1,258 case studies from 201 published research papers. Professor Bradley said that one of the primary goals was to understand how impacts accumulate during an invasion in order to support evidence-based management.

“We know that invasive species have negative impacts, but past meta-analyses have only looked at studies where invaders were absent vs. present.”

Professor Bradley explained that for native species faced with an invader at the same trophic level, where the two are likely competing for resources, there is a “strong negative linear response," but no sharp initial decline. “As you increase invasive species' abundance, the native species decline in abundance and in community diversity. The management implications are that if you control the invasion at any point, it's a win for ecosystems.”

On the other hand, when an invader enters at a lower trophic level than the native species, the results were not as clear.

“It could be creating new resources or it could compete against resources that the natives need. It's not clear whether the effects will be positive or negative, unless you're talking about terrestrial plants. Invasive plants are likely to have negative effects on native insects.”


Ultimately, the study authors concluded that “increasing the abundance of invasive alien species has pronounced negative impacts on native species populations and communities.” They said the fact that rapid declines in native populations have been found to occur at initial stages of the invasion process “highlights the increasing need for early detection and rapid response (EDRR) to new invasive alien species.”

“Avoiding the ecological impacts of invasive species will require a much stronger commitment to proactive policies designed to prevent novel introductions as well as increased management targeting the early stages of invasion.”

The study is published in the <a href="https://www.pnas.org/">Proceedings of the National Academy of Sciences</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

Image Credit: CJB Sorte/UC Irvine

Early detection is key to preventing damage from invasive species

An international research team led by the University of Massachusetts...

A new study led by <a href="https://www.rutgers.edu/">Rutgers University</a> has revealed that <a href="http://www.earth.com/news/global-warming-antarctica-green/">global warming</a> has caused twice as many ocean-dwelling species to disappear from their habitats compared to terrestrial species. According to the researchers, the greater vulnerability of marine animals may significantly impact coastal communities that rely on fish for food and economic security. 

The research is the first of its kind to compare the susceptibility of cold-blooded marine and land animals to global warming. The team also investigated the ability of various species to remain in their natural habitats while finding refuge from the heat.

The researchers reviewed studies on nearly 400 species such as fish, lizards, and spiders. They estimated safe conditions for 88 marine and 294 land species and examined the coolest temperatures available to them during the hottest parts of the year.

“We find that, globally, marine species are being eliminated from their habitats by warming temperatures twice as often as land species,” said lead author Professor Malin Pinsky. “The findings suggest that new conservation efforts will be needed if the ocean is going to continue supporting human well-being, nutrition and economic activity.”

The experts determined that marine species are more likely to experience dangerously high temperatures. Furthermore, many land animals can hide from the heat in forests or underground, which is not an option for most sea creatures. 

The study authors noted that past extinctions have often been concentrated at specific latitudes when the climate changed rapidly. As global warming continues, more  species will vanish from their local ocean habitats, which will have cascading impacts across other marine ecosystems. 

“Understanding which species and ecosystems will be most severely affected by warming as climate change advances is important for guiding conservation and management,” wrote the researchers.

The study is published in the journal <a href="https://www.nature.com/">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

Paid for by <a href="http://earth.com">Earth.com</a>

Image Credit: Malin Pinsky/Rutgers University-New Brunswick

Marine species are vanishing twice as fast as land species

A new study led by Rutgers University has revealed that...

Deep ocean animals are eating radioactive carbon from nuclear bomb tests. A new study has revealed that even the most remote and deep regions on Earth are not isolated from <a href="http://www.earth.com/news/mariana-trench-plastic-trash/">human activities</a>. According to the research, radioactive carbon leftover from nuclear bomb tests in the 1950s and 1960s has made its way to the bottom of the ocean. 

Researchers have discovered that crustaceans that live at the bottom of the ocean are eating radioactive carbon that has passed through the food web. 

A study detailing the findings was published in the <a href="https://sites.agu.org/">American Geophysical Union’s</a> journal Geophysical Research Letters. 

“Although the oceanic circulation takes hundreds of years to bring water containing bomb [carbon] to the deepest trench, the food chain achieves this much faster,” said Ning Wang, the lead author of the new study.

Nuclear bomb tests in the 50s and 60s released radioactive carbon-14 into the atmosphere. Once nuclear tests ended, the amount of carbon-14 or “bomb carbon” in the atmosphere dropped, and the carbon left the atmosphere to settle on the ocean’s surface.

Over time, marine organisms incorporated this carbon into their cells and researchers observed elevated levels of carbon-14 in marine animals after nuclear bomb testing started. 

Because carbon-14 is also created naturally when cosmic rays interact with nitrogen in the atmosphere, nearly all living things on Earth have some amounts of radioactive material in their systems. 

Carbon-14 is also a useful measure of dating geological and archeological samples. 

In a new study, researchers used bomb carbon to study and analyze organisms that thrive in the deepest parts of the ocean. 

Samples were collected from as deep as seven miles below the surface where temperatures are freezing and pressures high. 

Amphipod specimens, which are crustaceans that scavenge along the deep ocean floor and eat waste and dead organisms, collected in 2017 from the Mariana, Mussau, and New Britain Trenches in the tropical West Pacific Ocean were analyzed for the study. 

The amphipods had unusually high levels of carbon-14 in their stomachs and muscles, and the levels were similar to those found in surface marine organisms, suggesting that deep ocean organisms are eating carbon-14 contaminated waste and dead organisms that sink from the surface. 

The study sheds insight on the eating habits and lifespan of organisms that thrive in extreme and nutrient-poor environments, and the results show how human activities impact the environment. 

“There’s a very strong interaction between the surface and the bottom, in terms of biologic systems, and human activities can affect the biosystems even down to 11,000 meters, so we need to be careful about our future behaviors,” said Weidong Sun, a co-author of the study. “It’s not expected, but it’s understandable, because it’s controlled by the food chain.”

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By<a href="mailto:kayvandette@gmail.com"> Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Deep ocean animals are eating radioactive carbon from nuclear bomb tests

Deep ocean animals are eating radioactive carbon from nuclear bomb...

Even <a href="https://www.earth.com/news/great-white-sharks-mercury-arsenic/">great white sharks</a>, an apex predator of the ocean, would rather not face off against orca whales, according to a new study.

Researchers from the <a href="https://www.montereybayaquarium.org/">Monterey Bay Aquarium</a> observed interactions between great white sharks and orcas off the coast of San Francisco in the <a href="https://farallones.noaa.gov/">Greater Farallones National Marine Sanctuary</a> and found that great whites surrender their territory as soon as orcas are spotted in the area. 

“When confronted by orcas, white sharks will immediately vacate their preferred hunting ground and will not return for up to a year, even though the orcas are only passing through,” said Dr. Salvador Jorgensen, lead author of a study documenting the new findings published in the journal Nature Scientific Reports. 

Altercations between top predators on land are a well-documented occurrence, but little research has extended to top marine predators. 

At the Farallones, great white sharks prey on vulnerable elephant seals between September and December each year. 

For the study, the researchers were lucky enough to document four encounters between sharks and orcas in the region. 

Data from 165 tagged white sharks from 2006 through 2013 as well as 27 years of seal, shark and orca surveys from the Farallones were reviewed and analyzed for the study. 

“The research in this paper combines two really robust data sources,” said Jim Tietz, co-author of the study. “By supplementing the Aquarium's new shark tagging data with Point Blue's long-term monitoring of wildlife at the Farallon Islands National Wildlife Refuge, we were able to conclusively show how white sharks clear out of the area when the orcas show up.”

As soon as orcas arrived, the researchers found that white sharks fled and only returned the next season. In some cases, the sharks left minutes after the arrival of orcas in the area and moved to elephant seal colonies farther along the coast. 

It’s hard to believe that a predator as massive and ferocious as the great white would swim away from orcas rather than risk an altercation, but that’s precisely what happens. 

“These are huge white sharks. Some are over 18 feet long (5.5 meters), and they usually rule the roost here,” said Anderson. “We've been observing some of these sharks for the past 15 to 20 years -- and a few of them even longer than that.”

Interestingly, despite being hunted by orcas, elephant seals benefit from having orcas in the area, and the researchers found that there were fewer elephant seal deaths when great whites vacated their hunting grounds. 

The study adds an important new element to consider when studying predator-prey relationships. 

“We don't typically think about how fear and risk aversion might play a role in shaping where large predators hunt and how that influences ocean ecosystems,” said Jorgensen. “It turns out these risk effects are very strong even for large predators like white sharks -- strong enough to redirect their hunting activity to less preferred but safer areas.”

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By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Even great white sharks flee from orcas

Even great white sharks, an apex predator of the ocean,...

Why do some animals eat their young?. Many mammals, insects, fowl, and reptiles have been documented <a href="https://www.earth.com/news/cannibalistic-frogs-endangered-species/">eating or abandoning some of their young</a>, but the reason for this cannibalistic behavior has puzzled the scientific community until now. 

Researchers from the <a href="https://www.utk.edu/">University of Tennessee</a> and the <a href="http://www.ox.ac.uk/">University of Oxford</a> used a mathematical model to help provide context to filial cannibalism and offspring abandonment and found that overall, animal parents who engage in these behaviors do so to benefit their other offspring. 

The researchers detailed their findings in a new study published in the journal Frontiers in Ecology and Evolution.

Quality control, disease risk, short supply of resources and overcrowding are all potential threats to newly born offspring, and for animals that birth large litters or clutches, these threats are intensified. 

“For example, in the beaugregory damselfish, fathers were more likely to eat eggs under low oxygen conditions,” said Hope Klug, a senior author of the study. “Such cases have led to the hypothesis that eating or abandoning offspring may be an adaptation to improve overall survival of offspring by reducing their density.”

In this context, filial cannibalism or abandonment may be an extreme form of parental care. 

To explore this idea further, the researchers turned to mathematical modeling to better understand the benefits of eating offspring. The researchers focused on egg-laying animals like reptiles and chickens. 

“The model introduced an imaginary individual with a mutation for filial cannibalism or offspring abandonment, into a population of generic egg-laying animals,” said Dr. Mackenzie Davenport, a lead author of the study. 

The gene for cannibalism spread through the population if filial cannibalism benefitted the parents and provided extra calories. 

The researchers also found that egg-laying density increased offspring mortality which helps confirm the idea that filial cannibalism or abandonment is a choice that ensures more offspring survive in the long run. 

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By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Why do some animals eat their young?

Why do some animals eat their young?. Many mammals, insects,...

According to the global news agency <a href="https://www.afp.com/en">AFP</a>, a UN report that has not yet been released is set to reveal that as many as one million species are facing extinction as a result of human activities. The 44-page Summary for Policymakers, which is an abridged version of a massive 1,800-page UN assessment, details an irrefutable connection between biodiversity loss and human-induced global warming.

The experts describe how humans have undermined the resources that we need the most for our survival. They warn that dwindling resources, including the loss of drinkable water, clean air, pollinating insects, and forests, pose no less of a <a href="http://www.earth.com/news/humans-hunted-6th-extinction/">threat to the future</a> of our planet than climate change. 

Robert Watson is the chair of the <a href="https://www.ipbes.net/">Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services</a> (IPBES), which is the independent body that was mandated by the UN to prepare the upcoming report. 

“We need to recognize that climate change and loss of Nature are equally important, not just for the environment, but as development and economic issues as well,” Watson told AFP. “The way we produce our food and energy is undermining the regulating services that we get from Nature.” He also noted that only “transformative change” can limit the damage.

The IPBES assessment ranks the direct causes of species loss in order of importance: shrinking habitats and land-use changes, overhunting or illicit trade in body parts, climate change, pollution, and invasive species. 

The authors of the investigation explain that a rapid acceleration in the global rate of species extinction is inevitable, stating that the rate of species loss “is already tens to hundreds of times higher than it has been, on average, over the last 10 million years.”

There are an estimated eight million distinct species living on Earth today, and the IPBES has confirmed that an astounding number of them may vanish within our lifetime. “Half-a-million to a million species are projected to be threatened with extinction, many within decades,” the report states.

Delegates from 130 nations will meet in Paris on April 29 to meticulously review the executive summary, just ahead of its release on May 6.

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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
Paid for by <a href="http://earth.com">Earth.com</a>

One million species may vanish as a result of human activities

According to the global news agency AFP, a UN report...

These fish can see colors even in the darkest depths of the ocean. An international research team led by scientists at the <a href="https://www.uq.edu.au/">University of Queensland</a> has discovered that fish living up to 1,500 meters deep in the ocean may have the remarkable ability to see color in dark waters. This extraordinary vision likely developed as a survival mechanism to help the <a href="http://www.earth.com/news/shipwrecks-artificial-reefs-fish/">fish</a> distinguish predators from prey. 

According to the experts, the research sheds new light on the evolution of vision in vertebrates, including humans. 

Dr. Fabio Cortesi of the UQ Queensland Brain Institute explained that vertebrates use rods and cones, which are two types of photoreceptor cells, in order to see. “Cones are used in bright-light conditions, while rods are generally used in dim-light.”

Proteins called opsins are present in both rods and cones to absorb light at specific wavelengths. Dr. Cortesi said that color vision among vertebrates is made possible by four different opsins used in cones.

“This variety allows sensitivity to a broad range of colors,” said Dr. Cortesi. “Ninety-nine percent of all vertebrates have just one opsin protein in their rods, so most are color-blind in dim-light conditions because they rely only on that single rod opsin.”

Dr. Fanny de Busserolles is a UQ deep-sea visual ecology specialist. She explained that most of the light is filtered out at depths of 200 to 1,500 meters below the surface of the ocean. “Down there it's very monochromatic, and most fish just perceive blue light. But we have discovered some spectacular exceptions.”

The investigation was focused on an analysis of the genomes of 101 species of fish. “We found 13 species had more than one rod opsin gene, and one - the silver spiny fin fish - had a remarkable 38 of these opsins,” said Dr. Cortesi.

Experiments and testing of how these rod opsins function indicated that silver spiny fins are able to pick up a wide range of wavelengths of light, which means they can probably see many colors.

“There are many colors of bioluminescence - light produced and emitted by living organisms - down there, and it mainly appears in flashes coming from other fish,” said Dr. Cortesi. “If you want to survive down there you need to quickly decide if you are seeing a potential predator or potential prey.”

The study is published in the journal <a href="https://www.sciencemag.org/">Science</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

Image Credit: Dr. Wen-Sung Chung, University of Queensland, Australia

These fish can see colors even in the darkest depths of the ocean

These fish can see colors even in the darkest depths...

Snakebites are a major health crisis and a long neglected one. According to the <a href="https://www.who.int/news-room/fact-sheets/detail/snakebite-envenoming">World Health Organization</a>, around 5.4 million people are bitten by snakes each year worldwide, resulting in 81,000 to 138,000 deaths and three times as many amputations. 

While treatable, antivenoms rely on archaic 19th-century methods to create treatments that are not always effective or even accessible to tropical and subtropical communities where the <a href="https://www.earth.com/news/risk-death-snake-bites/">burden of snakebite injury and death is highest</a>. 

A new initiative will hopefully create some much-needed progress in snakebite treatment research as well as funding. 

Britain's <a href="https://wellcome.ac.uk/">Wellcome Trust</a>, a global health charity, has announced plans to donate $102 million to snakebite treatments in the hopes of improving antivenoms, making treatments widely and easily accessible, and creating more effective snakebite drugs. 

Snakebites have been declared a “hidden health crisis” prompting the Wellcome Trust to action. 

Rural communities in Africa, Asia and South America are most at risk of amputation or death due to snakebites, but very little progress has been made in treating these very treatable injuries. 

To create an antivenom, horses are injected with a small dose of snake venom. The horse is unaffected by the toxin but blood taken from the horse is used to create antivenoms for humans, a hardly scientific process with few safety standards. 

“Snakebite treatment is essentially reliant on a 100-year-old process,” David Lalloo, a professor and director of Britain’s Liverpool School of Tropical Medicine, told <a href="https://www.reuters.com/article/us-health-snakes/hidden-health-crisis-of-snakebites-gets-100-million-funding-injection-idUSKCN1SL2Y9">Reuters</a>. 

While there will always be poisonous snakes that pose a risk to people worldwide, the lack of safe and accessible treatment highlights a lack of progress in antivenoms. 

“Snakebite is – or should be – a treatable condition. With access to the right antivenom there is a high chance of survival,” said Professor Mike Turner, director of science at Wellcome. “It’s an incredibly challenging issue – there has been almost no investment in snakebite research over the last decade – but it’s also one that is solvable with support from WHO, national governments, industry and other funders.”

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By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Snakebites declared a ‘hidden health crisis’ around the globe

Snakebites are a major health crisis and a long neglected...

Hunting has caused a decline in mammals in half of intact tropical forests. Researchers from <a href="https://www.ru.nl/english/">Radbound University</a> have determined that hunting is responsible for a 40% average decline of large mammals in the remaining small percentage of intact tropical forests. 

An estimated 20% of tropical forests in the world remain undisturbed by logging or deforestation. However, increased human accessibility to these areas has made <a href="http://www.earth.com/news/wildlife-losses-climate-consequences/">hunting</a> the biggest threat to mammals in these environments.

Unlike deforestation, overhunting goes undetected by remote-sensing techniques, and hunting impacts (specifically, “defaunation” — the loss of species or decline in animal populations) in remote areas have only recently been discussed because of this prior lack of data.

The research team from Radbound have, for the first time, documented the spatial patterns of mammal defaunation caused by hunting, and have located specific areas where impacts of hunting are the highest. They did so by using a newly developed hunting regression model, which takes 40 years worth of socio-economic data, like human population density and hunters' access points, as well as species traits of over 300 mammal species, into account.

These hunting hotspots include West and Central Africa (specifically Cameroon), Central America, northwestern regions of South America, and areas in Southeast Asia (specifically Thailand, Malaysia and southwest regions of China).

Their data is published in <a href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3000247">PLOS Biology.</a>

These new defaunation maps will become an important part of future global biodiversity assessments, and could help species that are currently in danger of being over hunted come back from the brink of endangerment or extinction.

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By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Image Credit: Ruth Archer/Pixabay

Hunting has caused a decline in mammals in half of intact tropical forests

Hunting has caused a decline in mammals in half of...

After a recent global assessment of biodiversity found that <a href="https://www.earth.com/news/one-million-species-vanish/">one million species are now threatened with extinction</a> due to human activities, a new study suggests that urban environments could serve as a potential conservation lifeline in the coming years. 

Urban areas, densely populated with people and lacking in green space, are considered “low-quality habits.” These habitats may offer some sources of food for pollinators but are not suitable for population growth. 

Researchers from <a href="https://www.tufts.edu/">Tufts University</a>, the <a href="https://www.liverpool.ac.uk/">University of Liverpool</a>, <a href="https://wsu.edu/">Washington State University</a> and the <a href="https://uiowa.edu/">University of Iowa</a> conducted a study to assess the viability of low-quality habitats in aiding conservation efforts.  

The study, published in the journal Ecology, shows that urban areas are much more useful for pollinators than previously realized and that many species take advantage of low-quality habitats in order to reach high-quality habitats quickly. 

It’s in high-quality environments that species that thrive and reproduce. 

The researchers reviewed data from 70 studies involving 78 species in total and found that 73 percent of the time, the animals moved quickly and efficiently through low-quality habitats to get to a high-quality area. 

This allowed for rapid range expansion evidenced by the Baltimore checkerspot butterfly, which was able to reach suitable habitats quickest in landscapes made up of 85 percent unstable habitat and 15 percent high-quality habits. 

“At landscape scales, 15% high-quality habitat is still more than currently exists in most ecosystems,” said Elizabeth Crone, the lead author of the study. “Nonetheless, our findings point to the potential of using suburban and even urban greenspace as underappreciated areas that could facilitate range shifts, if green spaces such as lawns were converted to native plant gardens, which have high conservation potential for insects and other wildlife species.” 

The results of the study show that urban landscapes are useful to population growth and biodiversity. 

“This could offer a new perspective of flexibility for landscape planners: they needn’t worry if they can’t create unbroken tracts of high-quality wildlife habitat, instead they can create strategic ‘stepping stones’ in urban and agricultural areas,” said Jenny Hodgson, a co-author of the study. 

“However, the stepping stones need to provide resources for breeding, not just temporary food resources.”

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By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>,<a href="https://www.earth.com/"> Earth.com</a> Staff Writer 

Paid for by <a href="http://earth.com">Earth.com</a>

Image Credit: Leone Brown, Tufts University

Urban areas offer surprisingly useful ‘stepping stones’ for at-risk species

After a recent global assessment of biodiversity found that one...

Wind turbines kill tens to hundreds of thousands of bats each year, according to the <a href="https://www.usgs.gov/faqs/how-are-bats-affected-wind-turbines?qt-news_science_products=0#qt-news_science_products">US Geological Survey,</a> and there are more than 52,000 wind turbines in operation in the US today. 

As renewable energy becomes more of a priority and wind and solar farms expand across the country, it’s crucial to consider how technology like wind turbines and solar panels <a href="https://www.earth.com/news/wind-turbines-hurt-robins/">impact wildlife.</a>

Researchers from <a href="https://www.tamu.edu/">Texas A&amp;M University</a> have developed a whistle that mimics that sound a bat makes and can be mounted on wind turbines to warn bats if they’re in danger of coming too close.

Not only do the propeller-like blades of the turbines pose a risk to bats who can collide with the turbines, but the pressure difference created by the rotating turbine can cause the lungs of bats to explode. 

The researchers were able to develop a whistle that emits sounds at a frequency that bats can easily register and recognize. 

“Our approach focuses on producing a sound bats could easily recognize and locate, thereby making it easier for them to avoid the moving turbine blades,” said Michael Smotherman, a researcher who worked on the whistle project. “I’m hopeful that using this neuroethological approach to the design and implementation gives us a better chance for success.”

The researchers used biomimetics to mimic the natural sounds produced by a bat’s larynx and created a whistle modeled after the anatomical structures in the larynx.  Bats can naturally produce multi-harmonic tones that can be heard up to 100 meters away. 

After testing the whistle in a lab setting and discovering that bats responded to the sounds, the researchers moved their work to the field and hope to test the whistle on real-world wind turbines soon. 

The whistles can be 3D printed but installing them on wind turbines will be costly unless the researchers find ways to cut costs. 

Smotherman will present his team’s work on the new whistle at the 177th Meeting of the <a href="https://acousticalsociety.org/">Acoustical Society of America</a>.

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By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>,<a href="https://www.earth.com/"> Earth.com </a>Staff Writer

Whistle alerts help bats stay away from deadly wind turbines

Wind turbines kill tens to hundreds of thousands of bats...

<a href="https://www.earth.com/news/antimicrobial-resistance-worldwide/">Antimicrobial resistance </a>(AMR) is a growing global public health crisis, particularly in developing nations where unregulated antibiotic use and poor waste management practices are common. 

Health officials estimate that this year alone, 700,000 people will die globally from antimicrobial resistance, and in the next 30 years the annual death toll could reach 10 million. 

There are concerns that AMR increases the risk for the spread of untreatable diseases passed from wildlife to humans. 

While this hasn’t happened yet, it’s a threat that researchers are not taking lightly. 

In a new study, a team of researchers from the <a href="https://www.liverpool.ac.uk/">University of Liverpool</a> and the <a href="https://www.ilri.org/">International Livestock Research Institute</a> surveyed 99 households in Nairobi. Households were picked at random and the researchers collected samples to measure AMR prevalence across different neighborhoods. 

The team found that urban wildlife in Nairobi carry high levels of AMR bacteria resistant to drugs that the <a href="https://www.who.int/">World Health Organization</a> has said are critically important for medicine. 

There was a greater variety of AMR in livestock and the environment. Both rodents and birds were more likely to carry multiple AMR bacteria when exposed to human and livestock waste. 

The findings are troubling as it points to urban wildlife as a vector for AMR, and if that happens, the resistant bacteria would be able to spread quickly and efficiently through waterways, sewage lines, and carried by migratory birds. 

“This is not just specific to Nairobi, but findings can be extrapolated to other cities in Africa,” said Eric Fèvre, a member of the research team. “We tend to think of AMR in primarily medical terms, of developing new drugs and better using old ones. But we need to take an ecological approach to addressing this threat. Urban cities can address this by better urban planning, better waste disposal, better livestock husbandry practices.”

The study was published in the <a href="http://www.thelancet.com/journals/lanplh/article/PIIS2542-5196(19)30083-X/fullte">Lancet Planetary Health</a>.  

“As many scientists and policymakers are now realizing, we cannot address the rise of anti-microbial resistance without focusing on the environmental, ecological and social settings in which humans exist,” said James Hassell, the lead author of the study.

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By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer 

Image Credit: <a href="http://www.zoonotic-diseases.org">Zoonotic and Emerging Diseases (ZED)</a>

Antimicrobial bacteria could soon spread across cities through urban wildlife

Antimicrobial resistance (AMR) is a growing global public health crisis,...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



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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

Nushagak Bay in southwest Alaska

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Flu viruses are more flexible than expected

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



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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

Lake Trasimeno in Central Italy

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> describes a new self-powered nanosensor that can instantly detect mercury contamination with the tap of a finger.&nbsp;



The oxidized form of mercury can be harmful when it is ingested through contaminated water or food. This makes it necessary for experts to develop sensors that can quickly and accurately detect the presence of mercury.&nbsp;



Zong-Hong Lin and colleagues have now created a triboelectric nanosensor (TENS) that can detect mercury by simply by touching a sample. According to the researchers, their TENS could serve as the basis for similar devices to safely and remotely monitor other pollutants.



Video Credit: American Chemical Society&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Detecting mercury contamination with the tap of a finger

[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> explores the ability of salt to transform the way that foods and beverages taste. Salt is known to cover up undesirable flavors, such as bitterness in coffee or beer, but how exactly does sodium chloride change the taste of other compounds?



One previous study showed that, not only does salt suppress bitterness, but also enhances sweetness and sourness. Another study revealed that bitterness reduction by salt seems to be happening at the tongue receptor level as well as in the brain.&nbsp;



While it is known that salt taste is mediated by the presence of sodium channels in the form of taste buds, experts believe that there is also an unknown receptor responsible for how we taste salt that has not yet been identified.&nbsp;



Video Credit: ACS Reactions



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

How does salt makes things taste better?

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Santiago, the capital city of Chile. The city is located in the center of the Santiago Metropolitan Region, which has a population of about eight million people.&nbsp;



'The weather of Santiago resembles the Mediterranean climate with dry and warm summers with temperatures reaching up to 35°C (from October to March) and cool and humid winters that can drop to 0°C (from April to September)."



"The city lies in the centre of the country’s central valley around 80 km from the Pacific Ocean to the west and borders Argentina to the east. A tiny part of Argentina is visible in the top-right corner of the image where the mountain crest of the Andes Mountains acts as a divider between the two countries," says ESA.



Video/ Image Credit: ESA



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Santiago, Chile in South America

[sendtonews key="JRaP49ISmm-2357509-12187" type="single"] Today’s Video of the Day from the...

Spiral,Galaxy,,Illustration,Of,Milky,Way

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Astronomers at <a href="https://www.jhu.edu/">Johns Hopkins University</a> have created an interactive map of the universe, including the actual position and real colors of 200,000 galaxies. The map allows the public to access data that was previously only available to scientists.



The map was developed using data collected by the Sloan Digital Sky Survey. For over two decades, a telescope in New Mexico was aimed at slightly different locations to capture the night sky.&nbsp;



"Growing up I was very inspired by astronomy pictures, stars, nebulae and galaxies, and now it's our time to create a new type of picture to inspire people," said map creator Brice Ménard, a professor at Johns Hopkins. "Astrophysicists around the world have been analyzing this data for years, leading to thousands of scientific papers and discoveries. But nobody took the time to create a map that is beautiful, scientifically accurate, and accessible to people who are not scientists. Our goal here is to show everybody what the universe really looks like."



"In this map, we are just a speck at the very bottom, just one pixel. And when I say we, I mean our galaxy, the Milky Way which has billions of stars and planets. We are used to seeing astronomical pictures showing one galaxy here, one galaxy there or perhaps a group of galaxies. But what this map shows is a very, very different scale."



"From this speck at the bottom, we are able to map out galaxies across the entire universe, and that says something about the power of science."



The <a href="https://mapoftheuniverse.net/">interactive map</a> is available online, where it can be downloaded for free.



Video Credit: Johns Hopkins&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Interactive map of the universe includes 200,000 galaxies

[sendtonews key="e4ZG0Jawp3-2374785-12187" type="single"] Astronomers at Johns Hopkins University have created...

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Lesotho: Africa's "Kingdom in the Sky" Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features northwest Lesotho in South Africa.



According to ESA, Lesotho is the only nation in the world that lies completely above 1,000 m in elevation. The country is famous for its tall mountains and narrow valleys, and is known as Africa's "Kingdom in the Sky."



Out of a population of around two million people, about 80 percent live in rural areas. More than 75 percent of these people are engaged in <a href="https://www.earth.com/news/climate-change-will-have-a-global-impact-on-agriculture/">agriculture</a>, including rainfed cereal production and animal grazing.&nbsp;



ESA reports that the country’s agricultural system faces a growing number of issues, with climate-related vulnerabilities such as drought, floods and extreme temperatures occurring more frequently. 



Diamonds are amongst the minerals found in the mountains. Indeed, Lesotho can truly be called the Kingdom in the Sky. Beautiful, culturally rich, safe, affordable, and easily accessible from Durban and Johannesburg, mountainous Lesotho is a vastly underrated travel destination. the Kingdom of Lesotho (Sotho: 'Muso oa Lesotho) is an enclaved country in southern Africa. It is just over 30,000 km2 (11,583 sq mi) in size and has a population of around 2 million.



Video Credit: ESA&nbsp;&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Lesotho: Africa's "Kingdom in the Sky"

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Dublin, the capital and largest city of Ireland. Beyond its pub culture, Dublin is known as a modern culinary destination and a UNESCO City of Literature.



"Dublin is located near the midpoint of Ireland’s east coast in the province of Leinster. The city, which covers an area of around 115 square kilometers, is bordered by the Dublin Mountains, a low mountain range to the south, and is surrounded by flat farmland to the north and west," says ESA.



"The city straddles the River Liffey, which rises in the Wicklow Mountains and flows around 80 kilometers eastwards through the city of Dublin, in which it is canalised and bordered with quays. It then empties into Dublin Bay, an arm of the Irish Sea."



Dublin has an abundance of green spaces, including one of the largest enclosed public parks in any European capital city. Phoenix Park, which was originally formed as a royal hunting park in the 1660s, includes 707 hectares of green space.



Video Credit: ESA&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The city of Dublin on Ireland's east coast

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the province of Zaragoza in northeast Spain. The image was captured by the Copernicus Sentinel-2 mission.



"Together with the provinces of Huesca and Teruel, Zaragoza formed the old kingdom of Aragon. Its capital, also called Zaragoza (not visible in this image) is home to around half of Aragon’s population," says ESA.



"The Ebro River can be seen winding its way through the province from west to east in this image. Between its source in the Cantabrian Mountains in the northwest and its delta on the Mediterranean coast, the Ebro River is fed by more than 200 tributaries as it flows 910 km across much of northern Spain."



Since rainfall is very scarce in this region, irrigation in the Ebro basin is critically important. In the valleys surrounding the Ebro River, many fields are used for growing crops such as corn, wheat, and barley.



Video/ Image Credit: ESA



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The province of Zaragoza in northeast Spain

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> reveals the evolution of the Columbia Glacier in southeastern Alaska. Columbia is among the fastest shrinking glaciers in the world, and the video documents its rapid retreat over the years.&nbsp;



Columbia Glacier is a large, multi-branched calving glacier that flows out of the Chugach Mountains to the Prince William Sound.&nbsp;



According to USGS, Columbia had a long history of stability prior to 1980, with a length 41 miles, and small, short-lived advances or retreats.



In the years since 1980, however, satellite images have captured Columbia’s alarming retreat. By using false-color images, scientists can distinguish between snow and ice, open water, vegetation, and rocky debris on the glacier’s surface.



The series of false-color images featured in today's video were acquired over the span of 35 years. You can see that by 2021, the glacier’s main branch had retreated about 15 miles from its initial position.



The Columbia Glacier has also lost more than 50 percent of its volume, mostly due to calving. <a href="https://www.earth.com/video/nasa-reveals-3d-visual-of-an-atmospheric-river/">NASA</a> reports that while climate change likely started the retreat, mechanical processes kept the disintegration going.



The NASA images are provided by Jesse Allen, Robert Simmon, Joshua Stevens, and Lauren Dauphin using data from Landsat satellites, from the U.S. Geological Survey, and data from MODIS on NASA’s Terra satellite. The structure of Columbia’s moraine played a large role in the stability of the glacier before 1980. 



Like other tidewater glaciers, the Columbia built up a moraine over time, and the mixture of ice and rock functioned like a dam keeping out the sea. It was supported on one end by the shoreline and by the underwater terminal moraine at the other.



Video Credit: NASA Earth Observatory/&nbsp; NASA’s Scientific Visualization Studio



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



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The rapid retreat of the Columbia Glacier

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Pyrenees Mountains, which form a natural boundary between France and Spain in southwest Europe.



The mountain range is 430 kilometers in length. It stretches from the Mediterranean Sea on the east to the Atlantic Ocean on the west.



At an elevation of 3404 meters, Pico de Aneto is the highest mountain peak in the Pyrenees, and the third-highest peak in Spain. Pico de Aneto is located in the Posets-Maladeta Natural Park, which spans more than 82,000 acres.&nbsp;



"Geological studies have revealed that the Pyrenees Mountains have been around for longer than the Alps, with their sediments first deposited in coastal basins during the Paleozoic and Mesozoic eras," reports ESA.



"The entire mountain range formed due to the upwelling of large sedimentary rocks by the collision of the Iberian and the Eurasian plate around 100 to 150 million years ago, followed by intense erosion from ice and water."



The western Pyrenees receive more precipitation due to moisture blowing in from the Atlantic Ocean. The mountain range contains many lakes, several small glaciers, and some of the highest waterfalls in Europe.



Video &amp; Image Credit: ESA



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The Pyrenees Mountains in southwest Europe

[sendtonews key="6HyfrAJTBI-1831843-12187" type="single"] Today’s Video of the Day from the...

Earth,Like,Exoplanet,3d,Render

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes two exoplanets that are orbiting a star 218 light-years away. A team of researchers led by the University of Montreal has found evidence that these planets are "water worlds."



The experts used data from NASA’s Hubble and Spitzer Space Telescopes. They discovered that exoplanets Kepler-138 c and Kepler-138 could be composed largely of water.



"We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that's why we called them super-Earths," explained study co-author Björn Benneke.&nbsp;



"However, we have now shown that these two planets, Kepler-138 c and d, are quite different in nature and that a big fraction of their entire volume is likely composed of water. It is the best evidence yet for water worlds, a type of planet that was theorized by astronomers to exist for a long time."



Video Credit: NASA Goddard



Image Credit: NASA, ESA, and Leah Hustak (STScI)



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Two distant planets may be "water worlds"

[sendtonews key="QIoVYJqRBi-2434608-12187" type="single"] Today's Video of the Day from NASA...

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Satellites reveal how Earth's systems are interconnected Today’s Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes Earth’s interconnected systems, and how this network is affected by rising temperatures.&nbsp;



During 2020, average global temperatures matched the hottest year on record. The hurricane season was also record-breaking, with many of the storms intensifying at extraordinary speeds. Hot water in the ocean is fuel for hurricanes. The satellite data shows that it's all one interconnected system showing how Satellites reveal how Earth's systems are interconnected.



According to NASA, dust swept up from Northern Africa plays a major role in the formation of hurricanes, and is also a key source of fertilization in the Amazon rainforest. As a result of<a href="https://www.earth.com/news/seagrass-wasting-disease-is-fueled-by-climate-change/"> climate</a> change, dust plumes are expected to decline, which will have an effect on vegetation far away.&nbsp;



Images from Earth-observing satellites show how the world’s plant life is affected by natural disasters, fires, and deforestation. Satellites also reveal how widespread changes in vegetation impact waterways,&nbsp; the climate, air quality. Satellites communicate by using radio waves to send signals to the antennas on the Earth. "Earth From Space" is a groundbreaking two-hour special that reveals a spectacular new space-based vision of our planet. 



Video Credit: NASA Goddard&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Satellites reveal how Earth's systems are interconnected

[sendtonews key="JbW4VsY53O-1632195-12187" type="single"] Satellites reveal how Earth's systems are interconnected...

Today’s Video of the Day from the <a href="https://welcome.miami.edu/">University of Miami</a> Rosenstiel School of Marine and Atmospheric Science explores how changes in water temperatures have affected tiger shark habitats and movements in the North Atlantic Ocean. The study reveals that rising temperatures have caused the sharks to shift toward the poles over the past 40 years.



“Tiger shark annual migrations have expanded poleward, paralleling rising water temperatures,” explained study lead author Neil Hammerschlag. “These results have consequences for tiger shark conservation, since shifts in their movements outside of marine protected areas may leave them more vulnerable to commercial fishing.”



The researchers analyzed nine years of tracking data from satellite-tagged tiger sharks, combined with four decades of conventional tag and recapture data provided by National Oceanic and Atmospheric Administration (NOAA) Cooperative Shark Tagging Program.



The experts found that during the last decade of record heat, for every one-degree Celsius increase in water temperatures, tiger sharks migrated further poleward by over 400 kilometers. They also migrated two weeks earlier than usual to waters off the northeastern coast of the United States.



“Given their role as apex predators, these changes to tiger shark movements may alter predator-prey interactions, leading to ecological imbalances, and more frequent encounters with humans,” concluded Professor Hammerschlag.



Video Credit: University of Miami Rosenstiel School of Marine and Atmospheric Science



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Tiger sharks are shifting poleward as temperatures rise

Today’s Video of the Day from the University of Miami...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> is focused on the melt ponds that emerge during the spring and summer on the Greenland Ice Sheet, which is the largest ice mass in the northern hemisphere.



"Melt ponds are vast pools of open water that form on both sea ice and ice sheets and are visible as turquoise-blue pools of water in this Copernicus Sentinel-2 image," says ESA.



"When snow and ice melts atop glaciers, water flows in channels and streams and collects in depressions on the surface. These melt ponds can speed up the melting of the surrounding ice since they greatly reduce the ice’s ability to reflect sunlight."



"This can create a positive feedback where an increasing number of melt ponds absorb more heat which causes ice cover to melt even faster."



According to ESA, Greenland has been hit with a late-season heatwave that began in early September. This caused the type of melt event that usually occurs in the middle of summer.



"In a recent paper published in Nature Climate Change, scientists found that major sea-level rise from the melting of the Greenland ice cap is now ‘inevitable’ even if the burning of fossil fuels were to halt overnight," says ESA. "Using satellite observations of Greenland ice loss and ice cap from 2000 to 2019, the team found the losses will lead to a minimum rise of 27 cm regardless of climate change."



Video Credit: ESA&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Melt ponds on the Greenland Ice Sheet

[sendtonews key="qARzJPSabQ-2270617-12187" type="single"] Today’s Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> describes a new map of Mars that is providing insight into the planet’s watery past. The map also reveals where future missions could safely land on Mars.&nbsp;



The map has been created over the last decade using observations of water-rich rocks and mineral deposits. The images were captured by ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter.



"A big surprise is the prevalence of these minerals, with the map revealing hundreds of thousands of water-affected locations in the oldest parts of the planet," says ESA. "The new data will help answer exciting questions about Mars’ climate history, whether water was globally persistent or confined to short, intense episodes, and whether the conditions were ever suitable for life."



"Specifically, the map shows the locations and abundances of aqueous minerals. These are from rocks that have been chemically altered by the action of water in the past, and have typically been transformed into clays and salts."



According to John Carter of the Institut d’Astrophysique Spatiale (IAS), our collective understanding of Mars has been oversimplified. He explained that planetary scientists have tended to think that only a few types of clay minerals on Mars were created during its wet period, then as the water gradually dried up, salts were produced across the planet.



The new map shows that the composition of Mars is much more complicated than what we thought. For example, while many salts formed after Martian clays, there are some salts that are presumed to be older than some of the clays.&nbsp;



“The evolution from lots of water to no water is not as clear cut as we thought, the water didn’t just stop overnight. We see a huge diversity of geological contexts, so that no one process or simple timeline can explain the evolution of the mineralogy of Mars. That’s the first result of our study. The second is that if you exclude life processes on Earth, Mars exhibits a diversity of mineralogy in geological settings just as Earth does,” said Carter.



Video Credit: ESA



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The history of Mars is much more complex than we thought

[sendtonews key="qas3EhyI0Y-2220951-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.stowers.org/">Stowers Institute for Medical Research</a> describes how cavefish adapted to a sedentary lifestyle over tens of thousands of years. 



The experts found that the muscle metabolism of cavefish has been genetically reprogrammed over time. As a result, the animals have experienced major changes in their morphology and behavior. Despite these changes, however, the cavefish remain healthy and fit.



The research may provide new clues about the evolutionary consequences of prolonged physical inactivity in humans.&nbsp;



“It’s no surprise that people are moving less and less as technology has advanced,” said Rohner. “With cavefish, we have a unique system where we can study what might happen if people remained couch potatoes over very, very long periods of time.”



Video Credit: Stowers Institute for Medical Research



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Cavefish are healthy despite their sedentary lifestyle

[sendtonews key="vpljfR2VBX-2560867-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> some of the most incredible waves in the world, as seen by Landsat satellites.



"With more than 370,000 miles of coastline on Earth, there are plenty of places where epic waves build up, curl over, and hurtle toward the shore.- much to the thrill of surfers," says NASA. "There are some places where these waves are so magnificent that they can be seen from space."



"With the broad perspective of satellites, we can see how these iconic waves develop into the world’s tallest, longest, fastest, and heaviest."



Video Credit: NASA Earth Observatory&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Satellites capture the world's biggest and fastest waves

[sendtonews key="MHyhtebibJ-2200368-12187" type="single"] Today’s Video of the Day from NASA...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> describes why satellite images and measurements of our planet have become "essential to our survival, offering a new outlook of our world."&nbsp;



Rising sea levels pose one of the biggest societal threats associated with climate change. According to ESA, satellite altimeter missions such as Copernicus Sentinel-6 are essential in monitoring global and regional changes in sea level.



"Unbeknown to many, the island of Crete, Greece, plays an important role in the Copernicus satellite altimetry constellation and on an international stage," reports ESA.



"Satellite altimetry data have to be continuously monitored at the ESA’s Permanent Facility for Altimetry Calibration where different techniques have pioneered the use of transponders to provide the best measurements to validate satellite altimeters in space soon after launch."



Dr. Craig Donlon explains that, by understanding planet Earth through satellite measurements, we are able to find evidence of change.&nbsp;



Video Credit: European Space Agency&nbsp;



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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

Satellites have become essential to our survival

[sendtonews key="761m2QQvR1-2035772-12187" type="single"] Today’s Video of the Day from the...