Thirty‑five millennia may sound like a long time, yet for a mammal, it is practically yesterday. A new study uses whole‑genome data to show that the Norwegian lemming, Lemmus lemmus, split from its Siberian cousin only about 35,000 years ago.



“The Norwegian lemming is a key ecological species in the Fennoscandian tundra. Among other things, it serves as primary food for many predator <a href="https://www.earth.com/news/arctic-animals-evolved-in-different-ways-to-beat-the-cold/">species</a>, including some threatened ones such as the Arctic fox,” said David Díez del Molino, a researcher at the Centre for Palaeogenetics, <a href="https://www.su.se/">Stockholm University</a>.



<h2 class="wp-block-heading" id="h-lemmings-shape-arctic-life">Lemmings shape Arctic life</h2>



Ecologists have tracked lemming booms and busts for decades because those <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1046/j.1365-2656.1999.00258.x" target="_blank" rel="noreferrer noopener">cycles</a> ripple through the tundra food web, shaping the breeding success of Arctic foxes, owls, and even geese. 



When rodent numbers crash, fox litters shrink, snowy owls skip nesting, and grasses rebound after seasons of heavy grazing.



Unlike most small <a href="https://www.earth.com/news/world-water-day-2025-preserving-glaciers-protecting-our-future/">mammals</a>, Norwegian lemmings overwinter aboveground by tunneling under snow, a habit that keeps them active when many rodents lie low. Their winter wanderings aerate soil, mix plant nutrients, and feed predators during the hungriest months.



During peak years, the species can reach densities of hundreds per acre. Yet its loud squeaks and bold charge‑and‑bite defense make predators think twice, granting the animal an outsized ecological voice relative to its three‑ounce frame.



<h2 class="wp-block-heading" id="h-lemmings-became-a-separate-species">Lemmings became a separate species</h2>



Researchers compared nine modern and two ancient lemming genomes and found a clean split from the Western Siberian lemming with no evidence of crossbreeding, even in areas where the two meet today. 



That result stands in sharp contrast to polar bears and brown bears, whose DNA still shows <a href="https://pubmed.ncbi.nlm.nih.gov/22517859/" target="_blank" rel="noreferrer noopener">ancient admixture</a> from repeated hybridization events.



“Our findings indicate that the Norwegian lemming is among the most recently evolved <a href="https://www.earth.com/news/world-otter-day-2025-on-the-front-lines-of-a-habitat-crisis/">mammals</a>, diverging from its sister taxon, the Western Siberian lemming, at a remarkably shallow time depth,” said <a href="https://palaeogenetics.com/people/edana-lord/" target="_blank" rel="noreferrer noopener">Edana Lord</a>, a postdoctoral researcher at the Centre for Palaeogenetics.



The team’s high‑resolution sequencing also resolved relationships within the genus Lemmus, confirming that Eastern Siberian lemmings belong to a separate species and helping clean up a century of contested rodent taxonomy.



<h2 class="wp-block-heading" id="h-a-species-born-in-an-ice-age">A species born in an ice age</h2>



The divergence date places the split just before the <a href="https://www.science.org/doi/10.1126/science.1172873" target="_blank" rel="noreferrer noopener">Last Glacial Maximum</a>, when ice sheets peaked between roughly 26,500 and 19,000 years ago. 



Glacial barriers likely trapped an ancestral lemming population in a Scandinavian refuge, cutting gene flow with Siberian relatives and setting the stage for rapid speciation.



Once the ice retreated, the newly minted Norwegian lineage expanded westward, but climatic swings had already written separation into the animals’ DNA. Modern population genetics shows no trace of later contact, suggesting that geography and behavior together kept the young species distinct.



Because the entire living population coalesces to a common ancestor only about 6,400 years ago, every Norwegian lemming alive today shares surprisingly shallow roots, a reminder that dramatic evolutionary change can happen fast.



<h2 class="wp-block-heading" id="h-color-blocks-crossbreeding">Color blocks crossbreeding</h2>



Hybridization often lingers for thousands of years after a split, yet these rodents seem to have slammed the door shut. 



One reason may be their vivid black‑and‑yellow coat, a pattern that functions as an <a href="https://www.amnh.org/explore/news-blogs/aposematism-warning-signals" target="_blank" rel="noreferrer noopener">aposematic warning</a> and an instant badge of identity, reducing mating mistakes with the drab Siberian form.



Aggressive ritual boxing, loud chirps, and high‑speed chases further isolate the species by favoring individuals that court their own kind and bully outsiders away from snow burrows.



<h2 class="wp-block-heading" id="h-genes-that-power-survival">Genes that power survival</h2>



Sequencing uncovered unique changes in the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3093193/" target="_blank" rel="noreferrer noopener">LYST pigment gene</a> that help produce the lemming’s splashy jacket, a mutation class also linked to altered melanosome function in laboratory mice. 



The same region shows signs of a recent selective sweep, hinting at strong predator‑driven pressure for conspicuous colors.



Other <a href="https://pubmed.ncbi.nlm.nih.gov/30006135/" target="_blank" rel="noreferrer noopener">mutations</a> appear in <a href="https://www.ncbi.nlm.nih.gov/gene/53630" target="_blank" rel="noreferrer noopener">BCO1</a>, <a href="https://medlineplus.gov/genetics/gene/apob/" target="_blank" rel="noreferrer noopener">APOB</a>, and <a href="https://www.genecards.org/cgi-bin/carddisp.pl?gene=RELCH" target="_blank" rel="noreferrer noopener">RELCH</a> - genes involved in fat transport and storage; in mice, knocking out BCO1 triggers fatty‑liver disease and shifts cholesterol pathways. Extra‑efficient lipid metabolism may keep lemmings fueled through subzero winters when seeds are scarce.



The researchers also found clusters of rapidly evolving olfactory receptor genes, suggesting that a refined sense of smell guides the rodents through deep snow tunnels to mates, food, and lurking stoats.



<h2 class="wp-block-heading" id="h-lessons-for-arctic-mammals">Lessons for Arctic mammals</h2>



Climate upheaval can spin off new <a href="https://www.earth.com/news/aquatic-robot-inspired-by-flatworms-can-swim-in-harmony-with-nature/">species</a> in a geological blink, and the lemming’s youth underscores how quickly isolation plus selection can rewrite a mammal’s genetic blueprint. 



Similar patterns play out in Arctic whales, foxes, and hares as shrinking ice opens and closes migration corridors.



“This work represents a big step in our understanding of lemming speciation and evolution,” said Love Dalén, a professor in <a href="https://utbildning.su.se/english/education/course-catalogue/bl/bl7082" target="_blank" rel="noreferrer noopener">Evolutionary Genomics at Stockholm University</a>. 



Professor Dalén noted that tracing ancient DNA in more Pleistocene specimens could reveal exactly when each adaptive mutation took hold.



The study is published in <a href="https://www.pnas.org/doi/10.1073/pnas.2424333122" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



 n

How Norwegian lemmings rapidly evolved into a new species

Thirty‑five millennia may sound like a long time, yet for a mammal, it is practically yesterday. A new study uses whole‑genome data to show that the Norwegian lemming, Lemmus lemmus, split from its Siberian cousin only about 35,000 years ago. “The Norwegian lemming is a key ecological species in the Fennoscandian tundra. Among other things, it serves as primary food for many predator species, including some threatened ones such as the Arctic fox,” said David Díez del Molino, a researcher at the Centre for Palaeogenetics, Stockholm University. Lemmings...

A third of marine megafauna, including species of sea turtles and sharks, disappeared about two to three million years ago, according to a new study.

“The marine mega-faunal communities that humans inherited were already altered and functioning at a diminished diversity," said lead author Catalina Pimiento, who conducted the study at the Paleontological Institute and Museum of the <a href="http://www.uzh.ch/en.html">University of Zurich</a>.

The international team investigated fossils of marine megafauna from the Pliocene and the Pleisto-cene epochs (5.3 million to around 9,700 years BC).

The newly discovered extinction event affected marine mammals, which lost 55 percent of their diversity. As many as 43 percent of sea turtle species were lost, along with 35 percent of sea birds and 9 per cent of sharks, the study found.

On the other hand, new forms of life developed during the subsequent Pleistocene epoc. Around a quarter of animal species, including the <a href="https://www.earth.com/news/mercury-levels-polar-bears/">polar bear</a> Ursus, the storm petrel Oceanodroma, and the penguin Megadyptes, had not existed during the Pliocene. Overall, however, earlier levels of diversity could not be reached again, the authors said.

"Our models have demonstrated that warm-blooded animals in particular were more likely to become extinct,” Pimiento said. “For example, species of sea cows and baleen whales, as well as the giant shark Carcharocles megalodon disappeared.”

The study shows that marine megafauna were “far more vulnerable to global environmental changes in the recent geological past than had previously been assumed,”  said Pimiento.

In order to determine the consequences of the extinction, the research team concentrated on shallow coastal shelf zones, investigating the effects the extinction had on coastal ecosystems. Seven functional entities, groups of animals not necessarily related but that share similar characteristics in terms of the function they play on ecosystems, were lost in coastal waters during the Pliocene.

Even though the loss of seven functional entities a third of the species is relatively modest, this led to an important erosion of functional diversity. 17 percent of the total diversity of ecological functions in the ecosystem disappeared and 21 percent changed, the study said.

Previously common predators vanished, while new competitors emerged and marine animals were forced to adjust. In addition, the researchers found that at the time of the extinction, coastal habitats were significantly reduced due to violent sea levels fluctuations.

The study is published in the journal <a href="https://www.nature.com/natecolevol/">Nature Ecology &amp; Evolution</a>

--

By: <a href="mailto:dbeasley@earth.com">David Beasley, </a><a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="http://www.uzh.ch/en.html">University of Zurich</a>

Study uncovers widespread extinction of marine species

A third of marine megafauna, including species of sea turtles...

Survival of young steelhead trout in oceans has been declining “precipitously,” according to a new study.

In Puget Sound, south of <a href="https://www.earth.com/news/group-seattle-kids-advance-climate-change-lawsuit/">Seattle</a>, Washington, ocean survival of juvenile steelhead in the 2000s declined by 77% on average compared to the 1980s, the study found.

There were parallel declines in adult populations, which have dropped 53 percent on average since the 1980s, according to the study published in <a href="http://www.nrcresearchpress.com/journal/cjfas">Canadian Journal of Fisheries and Aquatic Sciences.</a>

Steelhead trout populations in British Columbia included in the study also have all declined since the 1980s.

The data can enhance current tools being used to predict changes in steelhead populations, said Neala Kendall, lead author of the study.

"Stakeholders and concerned citizens want to better understand why these populations have been struggling and how marine survival has contributed," she said. "With this information, policymakers and managers can have different expectations about Puget Sound and Lower Columbia steelhead [compared to] fish on the coast due to their different marine survival patterns.”

Kendall sees this study as providing further support for ongoing efforts by natural resource agencies and nonprofit organizations to improve steelhead survival and protect the habitats  juvenile trout use upon arriving in the ocean. These include reducing construction of seawalls, protecting and promoting forage fish, understanding the impacts of marine mammals, and decreasing exposure to parasites and chemical contaminants.

The research is part of the <a href="http://marinesurvivalproject.com/">Salish Sea Marine Survival Project</a>, a US-Canada collaboration of more than 60 organizations conducting research to understand why salmon and steelhead are dying in the Salish Sea.

--

By: <a href="mailto:dbeasley@earth.com">David Beasley, </a><a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="http://www.cdnsciencepub.com/">Canadian Science Publishing</a>

Young steelhead trout survival dropping quickly

Survival of young steelhead trout in oceans has been declining...

A male pheromone in mice enhances sexual behaviors in females, and may trigger aggression in males, a new study says.

The pheromone works by identifying distinct neural circuits and neurons that generate a particular behavioral response to specific chemical signals, according to the <a href="http://www.u-tokyo.ac.jp/index_e.html">University of Tokyo</a> study.

The findings point to a model for further investigating how sex-specific innate behaviors in living things are controlled, the authors said.

In most animals, the sense of smell and other sensory perception of chemical stimulus play a critical role in controlling instinctive behaviors. For instance, chemical signals from a partner, competitor, or predator elicit specific behavior in mice, namely mating, aggression and defensive behaviors.

Ever since a pheromone secreted by a female moth that attracts the opposite sex was identified in 1959, scientists have pinned down numerous chemicals that affect behavior in a wide variety of animal species, from insects to mammals to humans. Despite their growing database of known pheromones, scientists knew little about how the brain actually converts certain sensory input into appropriate behavioral output, especially in mammals, the authors said.

"It is widely known that some chemicals, especially odors, can impact an animal's instinctive behaviors even on first contact," says Kazushige Touhara, a professor at the University of Tokyo's Graduate School of Agricultural and Life Sciences, who supervised the study. "We assumed there was a neural mechanism in the brain that correctly connects important sensory information to appropriate behavioral centers in the brain."

In its study, the research group used a male pheromone, secreted from the tear gland, called ESP1 that has been shown to enhance sexual behaviors in female <a href="https://www.earth.com/news/extra-virgin-olive-oil-protects-brain/">mice</a>, while promoting aggression in males exposed to ESP1 in conjunction with unfamiliar male urine. Unlike other pheromones, which tend to be composed of a complex web of substances, ESP1 is a single purified chemical that is detected by a sole corresponding receptor, making it comparatively easy to track.

The group employed various viral tracing methods--infecting receptor-expressing neurons with a virus strain and watching them spread as they label infected cells with a fluorescent protein--to visualize the neural circuit downstream of the ESP1 receptor, to map the anatomical foundation that conveys ESP1 signals in the brain. The information of ESP1 was routed differently in males and females by neurons in a region of the brain called the amygdala, the study said.

--

By: <a href="mailto:dbeasley@earth.com">David Beasley, </a><a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="http://www.u-tokyo.ac.jp/index_e.html">University of Tokyo</a>

Male pheromone in mice enhances female sexual behavior

A male pheromone in mice enhances sexual behaviors in females,...

Bats carry a significantly higher proportion of viruses able to infect people than any other group of mammals, according to a new study by the nonprofit group <a href="https://www.ecohealthalliance.org/">EcoHealth Alliance</a>

The study team built a comprehensive database of all known viruses infecting over 750 <a href="https://www.earth.com/news/otter-fossil-mammals-migrated-america/">mammal</a> species and around 600 viruses. It used mathematical models to identify the host species characteristics associated with having a larger number of viruses capable of infecting people (zoonotic viruses).

Zoonotic potential is predicted by a host species evolutionary relatedness to humans, the degree of human-wildlife contact, and other factors including the taxonomic order it belongs to, the study said.

Researchers used this analysis to demonstrate for the first time that, after correcting for uneven research effort and other variables, bats harbor the highest proportion of zoonotic viruses of any mammal group. 

“In 2005, our team showed that SARS originates in bats,” said Peter Daszak, President of <a href="https://www.ecohealthalliance.org/personnel/dr-peter-daszak"> </a>EcoHealth Alliance and senior author of the study. “Ever since that finding, scientists have wondered whether bats are ‘special’ reservoirs for viruses.  We now show definitively that bats carry a higher proportion of yet-to-be-identified viruses of potential risk to people than any other mammal group.”

The research could help prevent pandemics, the study said. Bats are important to ecosystem health, through pollinating tropical fruits, removing insect crop pests and disease vectors, and providing other critical ecosystem services.

While the data show bats carry potentially important viruses, it’s important to remember that the only way these viruses can emerge in people is if we make contact with bats, alter their environment, hunt them or otherwise disturb their ecology, the authors said.  Effective bat conservation can help reduce the risk of zoonotic disease through better understanding and effective management of human-bat interactions.

The study uses the analyses to produce detailed maps showing where we are most likely to find as-yet-undiscovered viruses that could emerge in people, or “‘missing zoonoses.” For example, hot spots of ‘missing zoonoses’ for bats are in South and Central America and parts of Asia, for primates in tropical Central America, Africa, and southeast Asia. 

“The holy grail in pandemic prevention is to understand where the next zoonotic virus is likely to emerge and from what species,” said Kevin Olival, lead author of the study.

The study is published in the journal <a href="http://www.nature.com/nature/">Nature</a>.

--

By: <a href="mailto:dbeasley@earth.com">David Beasley, </a><a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="https://www.ecohealthalliance.org/">EcoHealth Alliance</a>

Bats most likely animal to carry viruses that can infect people

Bats carry a significantly higher proportion of viruses able to...

The arrival of millions of tiny sea pickles off the western coast of the United States has fisherman frustrated and scientists fascinated. 

Pyrosomes are cylinder-shaped colonies that contain thousands of organisms. Also known as sea pickles, pyrosomes are most commonly found in the surface layers of tropical waters.

They were first spotted off the coast of Oregon, and have now reached as far north as Sitca, Alaska. University of Oregon graduate student Olivia Blondheim is part of a new research team set up to study the phenomenon. 

“Right now we are scrambling to learn as much as possible while we have the opportunity,” Blondheim told <a href="https://www.theguardian.com/">The Guardian</a>. “If we continue to see this many, what impact will it have on the ecosystems here, and what economic impact on the fisheries? There are so many unknowns at this point, it really is a remarkable bloom.”

The researchers also want to determine what has caused the sudden appearance of sea pickles far from their tropical habitats. Warmer ocean temperatures as a result of climate change, unusual currents, or shifting animal diets are all potential influences of this unprecedented migration.  

“One of the things we are figuring out is have these guys been off the coast and we haven’t seen them? Are they moving inshore for a different reason?” said Blondheim.

The jellylike tubes can actually become as large as 60 feet, although the zooids that they are made up of are only a few millimeters in size. The zooids are connected by tissue and move as one entity. The colony is bioluminescent and glows in the dark. 

These unique organisms are asexual and clone themselves in a reproductive process known as budding. They reproduce and form new colonies very rapidly.

The pyrosomes first showed up off America’s west coast in the spring, and have become a major àggravation for the fisherman who encounter them. They prevent other fish from reaching the shore, and get caught in <a href="https://www.earth.com/news/fishermen-at-odds-over-new-fishing-laws-and-regulations/">fishing</a> nets and on hooks.

With reports from fisherman that the pyrosomes stretch “as far as the eye can see,” there is no telling when this rare event will end.  

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer 

Source: <a href="https://www.theguardian.com/">The Guardian</a>

Millions of sea pickles mysteriously appear on U.S. west coast

The arrival of millions of tiny sea pickles off the...

Yellowstone grizzly bears are no longer classified as an endangered species after the population dramatically rebounded in recent years, federal officials announced Thursday.

The population has grown from as few as 136 Yellowstone grizzly bears in 1975 to an estimated 700 today, the<a href="https://www.fws.gov/"> U.S. Fish and Wildlife Service</a> said.

"This achievement stands as one of America’s great conservation successes; the culmination of decades of hard work and dedication on the part of the state, tribal, federal and private partners,” said U.S. Secretary of the Interior Ryan Zinke.

The Greater Yellowstone Ecosystem Distinct Population Segment (DPS) consists of portions of northwestern Wyoming, southwestern Montana, and eastern Idaho. Grizzly bear populations outside of the DPS in the lower 48 states will be treated separately under the Endangered Species Act and will continue to be protected.

The federal government will return overall management of the grizzly population in the Yellowstone region to  the states and tribes.

The <a href="https://www.earth.com/news/climate-change-grizzly-bears/">Yellowstone</a> grizzly bear population is one of the best studied bear populations in the world, U.S. Fish and Wildlife said.

Population and habitat monitoring efforts indicate that Yellowstone grizzly bears have more than doubled their range since the mid-1970s. They now occupy more than 22,500 square miles, an area larger than the states of New Hampshire, Massachusetts, and Connecticut combined. 

The Yellowstone area is at or near its capacity to support grizzly bears, the federal government said.

Factors that helped the grizzly population recover include the quantity and quality of the habitat available and the state commitments to manage the population from now on in a manner that maintains its healthy and secure status, according to U.S. Fish and Wildlife.

“As a kid who grew up in Montana, I can tell you that this is a long time coming and very good news for many communities and advocates in the Yellowstone region,"  Zinke said. 

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By: <a href="mailto:dbeasley@earth.com">David Beasley, </a><a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="https://www.fws.gov/">U.S. Fish and Wildlife Service</a>

&nbsp;

Yellowstone grizzly bears are no longer endangered

Yellowstone grizzly bears are no longer classified as an endangered...

In recent years, medical marijuana has become a booming industry that has also paved the way for the legalization of recreational marijuana in a number of states. Legalized medical and recreational marijuana has quickly become a multi-billion dollar industry for humans, but is there a market for animals as well?

Despite cannabis still being illegal on the federal level, there is a legal gray area that allows pet owners to feed medicinal forms of marijuana to their <a href="https://www.earth.com/news/cats-domesticated-10000-years/">pets</a>. In many cases, it’s being used to treat ailments such as anxiety, cancer, ear infections, and arthritis.

“We are seeing about 20 percent growth every single month,' Alison Ettel, the founder of Treat Well, a company in California that makes non-psychoactive medical marijuana products for animals and humans, told <a href="http://www.dailymail.co.uk/sciencetech/article-4620230/Medical-marijuana-woos-four-legged-fans.html">Daily Mail</a>. “We probably get at least one to five cancer patients a day and the results we're seeing are just blowing my mind.”

Medical cannabis is currently legal in 29 states – plus Washington D.C., which has led to a sharp uptick in not only the number of humans using it as medicine, but animals as well. Ettel estimates that Treat Well is now treating thousands of animals.

Veterinarians are not allowed to prescribe marijuana for pets, so many owners will get a marijuana card for themselves in order to access medicine for their pets.

Supporters of medical cannabis for animas say that it provides a distinct advantage over other traditional drugs and painkillers, and it has no known side effects. Furthermore, medical cannabis can often be less expensive than other traditional medications.

However, some veterinarians are wary of the use of cannabis as a drug. “There are no studies on dogs or cats, much less guinea pigs or other species, so I don't know what the potential benefits could be, if any,” Ken Pawlowski, veterinarian and head of the California Veterinary Medical Association, told <a href="http://www.dailymail.co.uk/sciencetech/article-4620230/Medical-marijuana-woos-four-legged-fans.html">Daily Mail</a>.

Nevertheless, while certain loopholes still exist, owners are finding it beneficial to treat their pets with medical marijuana for certain ailments – and if it works, why wouldn’t they?

--

By <a href="mailto:certz@earth.com">Connor Ertz</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="http://www.dailymail.co.uk/sciencetech/article-4620230/Medical-marijuana-woos-four-legged-fans.html">Daily Mail</a>

Pet owners turning to medical marijuana to treat their animals

In recent years, medical marijuana has become a booming industry...

A bird’s egg shape may be related to the way it flies, a new study suggests.

"Perhaps streamlined birds need narrower eggs to negotiate their narrower pelvis, and because the only way to fit a chick into a narrower egg is to make the egg longer, elliptical or asymmetric eggs result," wrote Claire Spottiswoode of the <a href="https://www.cam.ac.uk/">University of Cambridge</a> in an article related to the study.

There are various theories about why the shape of bird eggs varies so widely across species. One theory, for example, holds that cliff-nesting <a href="https://www.earth.com/news/genes-determine-music-songbirds/">birds</a> lay more cone-shaped eggs - which would roll in a tight circle so as to not tumble off the cliff.

However, the new research yields evidence that variable egg shape is driven by unique flight adaptations. 

The study’s lead author, Mary Caswell Stoddard of <a href="https://www.princeton.edu/">Princeton University</a>, and her research team analyzed the shape of 49,175 eggs representing about 1,400 species in 37 orders, two of which are extinct. The eggs were categorized based on their asymmetry and/or ellipticity. 

The scientists also analyzed a wealth of biometric, life history, and environmental environmental parameters for all species.

The team used biometric measurements from museum specimens to calculate the hand-wing index (HWI) a standard proxy for flight efficiency and dispersal ability in birds.

They found that egg shape is not related to clutch size, environmental factors, or nest characteristics. However, there was a correlation between egg shape and HWI.

“Given that HWI is positively related to flight efficiency, these results raise the intriguing possibility that adaptations for flight may be key drivers of egg shape variation in birds,” the authors said.

--

By: <a href="mailto:dbeasley@earth.com">David Beasley, </a><a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="https://www.aaas.org/">American Association for the Advancement of Science</a>

Image Credit: M.C. Stoddard

Bird egg shape related to flight efficiency

A bird’s egg shape may be related to the way...

Zebrafish have a unique repair mechanism in their developing backbones that could provide insights into why human spinal discs degenerate with age, a new study found.

The repair mechanism apparently protects the fluid-filled cells of the notochord, the precursor of the <a href="https://www.earth.com/news/fossil-reveals-human-spine-originated/">spine</a>, from mechanical stress as a young fish begins swimming, the<a href="https://www.duke.edu/"> Duke University</a> study said. Notochord cells go on to form the gelatinous center of intervertebral discs, the flat, round cushions wedged between each vertebrae that act as shock absorbers for the spine.

In humans, the disappearance of these cells over time is associated with degenerative disc disease, a major cause of pain and disability worldwide.

"It is not difficult to speculate that these same mechanisms of repair and regeneration are present in humans at very early stages, but are lost over time," said Michel Bagnat of the Duke University School of Medicine and a senior author of the study. "If we are going to think about techniques that foster intervertebral disc regeneration, this is the basic biology we need to understand."

Bagnat likens the notochord to a garden hose filled with water. The hardy structure consists of a sheath of epithelial cells surrounding a collection of giant fluid-filled or "vacuolated" cells. During development, these vacuolated cells rarely pop, despite being under constant mechanical stress. Recent research has suggested that tiny pouches known as caveolae (Latin for "little caves") that form in the plasma membrane of these cells can provide a buffer against stretching or swelling.

To see whether the caveolae protected vacuoles from bursting, Duke researchers and collaborators from Germany generated mutants of three caveolar genes in their model organism, the zebrafish. Because these small aquarium fish are transparent as embryos, the scientists could easily visualize any spinal defects triggered by the loss of caveolae.

The researchers found that when the mutant embryos hatched and started swimming, exerting pressure on their underdeveloped backbones, their vacuolated cells started to break up.

Lead authors Jamie Garcia and Jennifer Bagwell took a closer look at the notochord of mutant fish. They marked the vacuolated cells green and the surrounding epithelial sheath cells red and then filmed the fish shortly after they hatched and started swimming. First, they could see an occasional vacuolated cell break and spill its contents like a water balloon. Then, over the course of fifteen hours, a nearby epithelial sheath cell would move in, crawl over the detritus of the collapsed cell, and morph into a new vacuolated cell.

The researchers then isolated live epithelial sheath cells and treated them with nucleotide analogs to show that they turned into vacuolated cells.

"These cells, which reside in the discs of both zebrafish and man, seem capable of controlling their own repair and regeneration," said Bagnat. "Perhaps it is a continuous release of nucleotides that is important for keeping the disc in good shape."

The study may offer insight not only into the development of back and neck pain, but also into the origins of cancer, the authors said.. Their data suggests that chordomas, rare and aggressive notochord cell tumors, may begin when epithelial sheath cells leave the notochord and invade the skull and other tissues.

The study is published in the journal <a href="http://www.cell.com/current-biology/home">Current Biology</a>.

--

By: <a href="mailto:dbeasley@earth.com">David Beasley, </a><a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="https://www.duke.edu/">Duke University</a>

Zebrafish spinal discs can repair themselves, could help humans

Zebrafish have a unique repair mechanism in their developing backbones...

In cities across the globe, rats are considered to be major pests that seem to be everywhere you turn. These rodents are known to spoil food, spread disease, and even start fires.

Despite these problems, a new study has found that rats are actually the least studied wildlife in New York City. “The most difficult challenge of urban rat research is finding suitable research sites (e.g. municipal businesses and dwellings) to obtain access to rats long enough to generate robust science,” explain the study’s authors in the <a href="https://academic.oup.com/jue">Journal of Urban Ecology</a>.

In order to conquer this challenge, the researchers have offered rather significant incentives to property owners in order to study the rats on their premises. These perks include free and confidential extermination services – after the rats have been studied, of course – and up to a $1,000 reward for information leading to research sites in Manhattan.

With greater access to private residences or businesses, researchers would be able to set up their expensive equipment and monitor the rats’ activity privately. Because rats are so perfectly adapted to their environment, they’re incredibly difficult to research without the proper set up. They can easily hide and avoid human contact.

The researchers believe that a better understanding of the ecology of city rats could lead to improvements in pathogen and <a href="https://www.earth.com/news/mathematical-fight-plant-diseases/">disease</a> surveillance, as well as a better understanding of their population distribution.

“We neglect to study them at our own peril,” says Michael Parsons, lead author of the study. “No war has ever decimated 1/3 of the human population. Rats have.”

Whether or not another black plague is in the future (let’s hope for “not”), studying these pests that inhabit many of the areas where we live and work can only help us to better understand them. 

--

By <a href="mailto:certz@earth.com">Connor Ertz</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="https://academic.oup.com/jue">Journal of Urban Ecology</a>, The Daily Mail

Why rats in major cities aren’t even being monitored

In cities across the globe, rats are considered to be...

<a href="https://www.earth.com/news/rampant-overfishing-gulf-california/">Overfishing</a> has devastating effects on aquatic species, and some fish stocks never recover. Scientists collected commercial whaling records to evaluate the devastating impact extreme fishing had on whale populations in the 20th century. The analysis will be used to prevent other marine populations from meeting the same fate. 

Decades of over harvesting whales for blubber, oil, and meat in the 20th century led to large collapses in the numbers of whale populations. 

Previous studies indicated that a sharp decline in population numbers can be expected when the group demonstrates a shift in body size or an irregular rise and fall in numbers. However, this research was conducted using experimental systems and had not been established in the wild. 

The research team examined data on the number and size of whales to see if signs of a rapidly declining whale population were present before the collapse was documented. Ecologist Christopher Clements of the <a href="http://www.uzh.ch/en.html">University of Zurich</a> led the team.

"We looked at data on blue, fin, sei and sperm whales and found significant declines in body size, with sperm whales taken in the 1980s four metres shorter on average than those in 1905,” Clements explained. "This means that warning signals were detectable up to 40 years before a population collapse.”

The findings of this study provide further evidence that a shift in the average body size of a marine population is a signal that the population is at risk of collapsing.

"Our technique could be used to help provide other species of conservation concern. Moreover, it could allow interventions to be put in place to stop this happening,” said Clements.

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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 

Source: <a href="http://www.uzh.ch/en.html">University of Zurich</a>

How collapsing whale populations can help save other species

Overfishing has devastating effects on aquatic species, and some fish...

With the ever-present threat of <a href="https://www.earth.com/news/republican-party-denial-climate-change/">climate change</a> having an effect on countless plant and animal species around the globe, it’s often hard to turn your focus to just one species. But what if that species was adorable beyond all belief? Enter: the hazel dormouse (Muscardinus avellanarius). It is a small rodent – but a very cute one – that lives in woodlands, scrub, and hedgerows. It eats flowers, nuts, and insects and sleeps for most of the day, as it’s nocturnal.

Currently, this tiny rodent is a European Protected Species and is being monitored by volunteers at sites in England and Wales. The monitoring effort is part of the <a href="https://surveydata.ptes.org/login">National Dormouse Monitoring Programme</a> – and if you look at a picture of these adorable creatures you may just want to sign up. The dormouse monitors make their counts during the day, when the animals are generally sleeping.

Unfortunately, despite these efforts, a recent analysis of data from 400 UK sites between 1993 and 2014 discovered a 72% decline in dormouse population. This adds up to an annual rate of decline of almost 6%.

Scientists believe the decline is ongoing, and signifies the possibility that dormice are endangered in the UK – however, the species is a top priority for conservation. “Dormice are declining despite strict protection and widespread efforts to conserve one of Britain’s most endearing woodland mammals,” says Cecily Goodwin, lead author of the<a href="http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-2907"> Mammal Review </a>study.

The authors believe that a host of problems are responsible for this decline, including climate change and habitat loss. “We think that appropriate woodland management could make a big difference," says senior author Prof. Robbie McDonald.

As efforts continue to track and monitor these tiny animals, it’s likely that the decline will continue until further efforts are made to prevent habitat loss. For now, let’s enjoy these cute critters while they’re still around.

--

By <a href="mailto:certz@earth.com">Connor Ertz</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Source: <a href="http://onlinelibrary.wiley.com/">Wiley Online Library</a>

Image Credit: Thames Water

This adorable rodent is on the brink of extinction

With the ever-present threat of climate change having an effect...

Scientists are transforming chocolate into a functional food by infusing it with probiotics and prebiotics, aiming to create a treat that satisfies cravings while supporting gut health. 



The challenge lies in maintaining chocolate's beloved texture and flavor while adding health benefits.



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Probiotics - beneficial microbes that balance gut bacteria and aid digestion - are typically fragile and can be destroyed by stomach acid or processing. 



Prebiotics act as food for these microbes, helping them thrive. Together, they form "synbiotics," a powerful health combination.



Researchers Smriti Gaur and Shubhi Singh from India's Jaypee Institute of Information Technology took an innovative approach, using natural prebiotics like corn and honey instead of complex processing methods. 



They created five chocolate varieties: a control and four synbiotic versions containing different combinations of prebiotics, probiotics (Lactobacillus strains), and flavor enhancers (cinnamon or orange).



Laboratory simulations of human digestion showed the probiotics remained viable for over five hours, suggesting they could survive long enough to benefit gut health.



Taste tests were positive, with researchers particularly enjoying the orange-flavored variety, describing it as having "vibrant citrus notes" complementing the "rich cocoa" with a "luxurious" texture.



This research represents just the beginning. With further refinement of strains, textures, and flavors, chocolate could evolve beyond mere indulgence to become a functional food that nourishes while it delights.



The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsfoodscitech.4c00741" target="_blank" rel="noreferrer noopener">ACS Food Science &amp; Technology</a>.

Is chocolate the next nutritional powerhouse?

Scientists are transforming chocolate into a functional food by infusing...

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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

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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...

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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



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 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

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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

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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

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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

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