Elasmosaurus,,Group,Of,Long-necked,Plesiosaurs,From,The,Late,Cretaceous,Period,

Scientists have pieced together evidence that ancient marine reptiles once swam in what is now central Colombia, and these creatures appear to have been more formidable predators than today’s mighty killer whales.&nbsp;



Their presence at an unexpectedly high level in the food chain has raised new questions about how ocean ecosystems evolve.&nbsp;



Paleontologists reconstructed the lives of giant reptiles and invertebrates that flourished in a lush environment roughly 130 million years ago, and uncovered a glimpse of life that sits outside what is considered standard for our modern seas.



<h2 class="wp-block-heading" id="h-marine-reptiles-ruled-over-killer-whales-nbsp">Marine reptiles ruled over killer whales&nbsp;</h2>



Experts discovered that some of these reptiles could exceed 33 feet (10 meters) in length, hinting at a way of life that appears to have been <a href="https://www.earth.com/news/ecosystem-behavior-earth-first-sea-creatures-stirring-water-drove-evolution/" target="_blank" rel="noreferrer noopener">remarkably powerful</a>.&nbsp;



According to their research, these creatures ruled the seventh level in a reconstructed Cretaceous food web, while present-day killer whales and great white sharks rarely pass the sixth.&nbsp;



At the heart of these findings is work by McGill University’s <a href="https://www.mcgill.ca/biology/" target="_blank" rel="noreferrer noopener">Department of Biology</a>, led by doctoral student Dirley Cortés and co-author Hans Larsson, who is a professor in the same department.



<h2 class="wp-block-heading" id="h-marine-reptiles-reached-the-pinnacle">Marine reptiles reached the pinnacle</h2>



Large predators typically dominate the top ranks in any oceanic food chain. Scientists often call these ranks "<a href="https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Introductory_Biology_(CK-12)/06%3A_Ecology/6.05%3A_Trophic_Levels" target="_blank" rel="noreferrer noopener">trophic levels</a>." 



Modern <a href="https://www.earth.com/news/ancient-sunken-oceans-discovered-between-earth-core-and-mantle/" target="_blank" rel="noreferrer noopener">marine</a> systems reach a natural limit around the sixth trophic (or feeding) level, where species like orcas hover at the pinnacle of the energy pyramid.&nbsp;



“Our study is the first to examine these possible ecological interactions,” said Cortés, who is lead author on the publication. 



By <a href="https://academic.oup.com/zoolinnean/article/202/1/zlad092/7275647?login=false" target="_blank" rel="noreferrer noopener">studying</a> fossil evidence in the <a href="https://www2.sgc.gov.co/LibroGeologiaColombia/tgc/sgcpubesp36201913.pdf" target="_blank" rel="noreferrer noopener">Paja Formation</a>, the team determined that Mesozoic reptiles had apparently gone one level higher. 



These ancient animals likely feasted on anything in their path, which explains how their food web stacked up so high.



<h2 class="wp-block-heading" id="h-reconstructing-a-lost-food-web">Reconstructing a lost food web</h2>



This investigation on ancient marine reptiles used body size, possible feeding tools, and comparisons with existing marine species to build a detailed framework for who ate whom in that vanished Colombian sea, where the warm climates of the Early Cretaceous allowed a surge in ocean diversity.&nbsp;



The Paja Formation’s fossil record reveals predators with robust jaws and swift movement, alongside an assortment of invertebrates that thrived in trophic levels beneath them.&nbsp;



Researchers drew upon modern <a href="https://www.earth.com/news/coral-disease-is-pushing-caribbean-reefs-toward-extinction/" target="_blank" rel="noreferrer noopener">Caribbean reef</a> networks to cross-check their results. 



By comparing these fossils to present-day communities, the study uncovered what one of the paper’s authors described as "intricate links among prehistoric animals" that pushed the boundaries of the marine hierarchy.



“Understanding this complexity helps us trace how ecosystems evolve over time,” said Cortés.



<h2 class="wp-block-heading" id="h-how-competition-shaped-the-seas">How competition shaped the seas</h2>



Marine food webs do not form overnight. Competition for resources tends to bring about new evolutionary strategies and unique feeding habits. 



During parts of the Mesozoic, <a href="https://www.pnas.org/doi/10.1073/pnas.0501562102" target="_blank" rel="noreferrer noopener">pressure</a> from marine predators and their potential prey made survival an ongoing challenge. 



A known surge in shell-crushing snails and other predatory invertebrates during this era has been labeled by paleontologists as the <a href="https://www.cambridge.org/core/journals/paleobiology" target="_blank" rel="noreferrer noopener">Mesozoic Marine Revolution</a>.&nbsp;



Ancient marine reptiles from the Paja Formation existed in this tense <a href="https://www.earth.com/news/looking-to-earths-ancient-climate-to-predict-our-future/" target="_blank" rel="noreferrer noopener">environment</a> of changing prey, leading them to develop massive body sizes and formidable hunting styles.&nbsp;



“These findings illuminate how marine ecosystems developed through intense trophic competition and shaped the diversity we see today,” said <a href="https://academic.oup.com/zoolinnean/article/202/1/zlad092/7275647?login=false" target="_blank" rel="noreferrer noopener">Larsson</a>.



<h2 class="wp-block-heading" id="h-why-this-matters-today">Why this matters today</h2>



The close study of creatures that roamed the ocean so long ago is not just about cataloging exciting fossils. Discoveries like this tell us that life’s history is packed with surprising adaptations.&nbsp;



Paleontologists see a chance to compare these ancient networks with modern ones, thus providing fresh insights into how ecosystems recover from challenges such as climate change or habitat loss.&nbsp;



Researchers also note that these fossil communities remind us of how species at the top of the food chain can alter their entire environment, often making space for additional biodiversity.



<h2 class="wp-block-heading" id="h-a-window-into-evolution">A window into evolution</h2>



One important lesson from this work is that <a href="https://www.earth.com/news/ancient-climate-shift-sheds-light-on-future-global-warming/" target="_blank" rel="noreferrer noopener">dramatic shifts</a> in ocean biodiversity occurred long before humans entered the picture. 



Marine reptiles vanished near the end of the Mesozoic, but the legacy of their top-heavy food webs is imprinted in the fossil record. 



Each puzzle piece from that record, from large jaws to specialized teeth, helps paint a more accurate picture of how Earth’s seas matured. 



The high trophic levels in the Paja Formation suggest that new habitats were emerging, allowing marine reptiles to reach body sizes and predatory niches that are rarely matched in modern times.



<h2 class="wp-block-heading" id="h-ancient-marine-reptiles-and-ecosystems">Ancient marine reptiles and ecosystems</h2>



Researchers plan to keep building models for other fossil sites. This work may reveal whether seventh-level predators were uncommon or if there were other pockets in Earth’s history where they thrived. 



In many regions, marine formations remain poorly understood, so there is every chance that the Paja Formation was not the only site containing marine reptiles with astonishing hunting powers.&nbsp;



More studies may show that, over millions of years, seas can produce predators more fearsome than anything we know today.



The study is published in the <a href="https://academic.oup.com/zoolinnean/article-abstract/202/1/zlad092/7275647?redirectedFrom=fulltext&amp;login=false" target="_blank" rel="noreferrer noopener">Zoological Journal of the Linnean Society</a>.&nbsp;



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.&nbsp;



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



-----

Top predators in prehistoric oceans would have eaten killer whales as snacks

Scientists have pieced together evidence that ancient marine reptiles once swam in what is now central Colombia, and these creatures appear to have been more formidable predators than today’s mighty killer whales.&nbsp; Their presence at an unexpectedly high level in the food chain has raised new questions about how ocean ecosystems evolve.&nbsp; Paleontologists reconstructed the lives of giant reptiles and invertebrates that flourished in a lush environment roughly 130 million years ago, and uncovered a glimpse of life that sits outside what is considered standard for our...

The environment in which humans and <a href="https://www.earth.com/news/dogs-help-children-improve-their-confidence-and-social-skills/">dogs</a> live has an effect on their reproductive health, according to a new study from the <a href="https://www.nottingham.ac.uk/">University of Nottingham</a>.

The researchers analyzed the link between geographical location and polluting chemicals present in dog testes, some of which are known to affect reproductive health. 

"In humans and dogs, a temporal decline in semen quality and increased incidence of testicular cancer is hypothesised to be associated with exposure to anthropogenic chemicals, particularly during fetal development," wrote the researchers.

"Human studies suggest that differential exposures to environmental chemicals may be associated with geographical differences in male reproductive health."

The experts chose to focus their study on dogs because they share the same environment as people and are effectively exposed to the same household chemicals as their owners.

The investigation revealed that the chemicals present, as well as any abnormalities in the testes, were different depending on where the dogs lived. 

"For the first time, we have shown that the profile of chemical pollutants found in dog testes depends on where they are from," said study lead author Dr. Rebecca Sumner.

"We have also shown that the same cohorts of dog testes also show geographic differences in testicular pathology and evidence of an imbalance in cells that are important for sperm production."

The researchers noted that for more than seven decades, the potential effects of anthropogenic chemicals on human male fertility have been of significant concern. 

"A series of widely cited meta-analyses have reported a temporal decline in human male semen quality and, over the same period, both increased incidences of testicular germ cell cancer in younger men and malformations of babies at birth have been reported," wrote the study authors. 

"This has led to the hypothesis that these abnormalities are linked to exposure to chemical pollutants and that these developmental and functional abnormalities have the same environmental origin."

Professor Gary England said the current study is of pivotal importance because it used dogs as a sentinel species for humans to focus directly on the testis, where chemicals are likely to influence male reproductive function.

"This work is significant since collectively, these findings indicate that environmental exposures are determined by location and this may underpin regional differences in male reproductive health."

The study is published in the journal <a href="https://www.nature.com/srep/">Scientific Reports</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Reproductive health is impacted by geographic location

The environment in which humans and dogs live has an...

Animals are able to create their own cultures just like humans, according to a study led by Professor Andrew Whiten at the <a href="https://www.st-andrews.ac.uk/">University of St. Andrews</a>. The research suggests that animals pick up cultural <a href="https://www.earth.com/news/beluga-whales-prioritize-family/">traditions</a> from their parents.

“The all-pervading cultural nature of our species was long thought to define what it is to be human, separating us from the rest of the natural world and the evolutionary processes that shape it," said Professor Whiten.

“Other species were thought to live by instinct and some ability to learn, but only humans had culture. Over recent decades, a rapidly growing body of research has increasingly revealed a very different picture.”

Professor Whiten argues that if culture is seen as traditions that are passed on by learning from others, culture is far from unique to humans. In this case, there is evidence of culture among a growing variety of animals, including mammals, fish, birds, and insects.

According to the study, examples of animal culture range from a group of chimpanzees that have a tradition of wearing a blade of grass in one ear to female fruit flies that copy the mate preferences of other females. 

“Culture even pervades animals’ lifetimes, from infancy to adulthood. The young of many species may first learn much from their parents, but increasingly learn from the different skills of others (as we humans do), even coming to focus on those in their group who display the greatest expertise, for example in using tools," explained Professor Whiten.

“Learning from others continues to be important into adulthood. Monkeys and apes dispersing as adults into new groups, avoiding inbreeding, have been found to adopt local habits different to those back home - ‘when in Rome, do as the Romans do’ appears a useful rule of what can be learned from the locals in an environment new to these animal immigrants.”

Professor Whiten said it must be recognized that culture is not a uniquely human capacity that emerged out of the blue, but that it has deep evolutionary roots. 

"Recognition of such practical implications of the reach of animal culture, along with implications for the broad range of scientific disciplines, should help assure a bright future for researchers in this field," said Professor Whiten.

"A new generation of scientists will now surely pursue the wider reaches of culture in animals’ lives, aided by the substantial armoury of methodological advances developed over the past two decades."

The study is published in the journal <a href="https://www.sciencemag.org/">Science</a>.   

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Humans are not the only animals that create their own culture

Animals are able to create their own cultures just like...

As the consumer electronics industry continues to grow, there is also a growing demand for the raw materials and metals used to make electronic components. Scientists at <a href="https://www.osaka-u.ac.jp/">Osaka University</a> have discovered a sustainable alternative to these finite resources in an unexpected place - crab shells. 

The researchers have developed a nanocarbon material for electronics applications made from chitin, one of the most important biopolymers in nature that is found abundantly in crab shells. 

According to the experts, nanocarbon materials show significant promise for use in electronic devices. Those with porous three-dimensional (3D) structures provide efficient networks for the transport of charge as well as electrolytes and reactants. 

Energy flow through nanocarbon materials can be made even more efficient with the addition of imperfections - known as defects - in the form of nitrogen and other chemical elements.

Porous nanocarbon materials have been previously developed using synthetic polymers and biomass for energy storage, sensing, and electrocatalysis. However, many of these materials were designed with non-renewable resources or require multiple steps to prepare the network and introduce the defects.

The researchers have now developed 3D porous defective nanocarbon materials through the simple pyrolysis, or thermal decomposition, of chitin nanofiber paper. Chitin is an ideal candidate for engineering electronics materials because it contains nitrogen atoms and acts as its own source of defects.

"We were able to control various properties of the final nanocarbon materials by pyrolyzing the chitin nanofiber paper at different temperatures," said study first author Luting Zhu. "The pore structure, specific surface area, and electrical resistivity all varied with the pyrolysis temperature, providing us with a useful means of tuning the material for specific applications."

The pyrolyzed chitin nanofiber papers were successfully used as photosensors - exhibiting lower resistance when exposed to light. They also proved effective as supercapacitor electrodes, with a higher capacity to store an electrical charge than many other nanocarbon materials. This indicates that chitin nanofiber papers have great potential for use in energy storage.

"In order to translate laboratory findings into products that make a significant impact in the real world it is important to streamline processes, which is why we are excited about our simple pyrolysis treatment," explained study co-author Hirotaka Koga. "Furthermore, our successful use of a renewable resource that is generally considered a waste product demonstrates the viability of sustainable electronics."

The study is published in the <a href="https://www.rsc.org/journals-books-databases/about-journals/journal-of-materials-chemistry-c/">Journal of Materials Chemistry C</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Crab shells could help pave the way for sustainable electronics

As the consumer electronics industry continues to grow, there is...

A team of researchers at the <a href="https://www.wcs.org/">Wildlife Conservation Society</a> (WCS) has discovered that a group of female monkeys use males as "hired guns" for protection.

The experts report that female putty-nosed monkeys use specific alarm calls to recruit males for protection when leopards and other <a href="https://www.earth.com/news/do-coral-reefs-depend-on-poop-from-their-predators/">predators</a> are nearby. 

The research was focused on 19 different groups of wild putty-nosed monkeys in Mbeli Bai, a study area within the forests in Nouabalé-Ndoki National Park, Northern Republic of Congo.

The results support the idea that female alarm calls require males to assess the nature of a threat. The study also confirms that the calls are used to recruit males for defense. 

The researchers noted that the female alarm calls do not cease until males produce calls associated with anti-predator defense. 

The observations suggest that alarm-calling strategies depend on the sex of the signaler. Females recruit males for protection, while males reassure the females that they are adequately protected. The male strategy likely ensures future mating opportunities as well.

When they are called upon for defense, the males use general "pyow" calls as they approach the rest of their group. These calls allow the female monkeys to recognize individual males, including the most high quality group defenders, from a distance.

The signature "pyow" calls likely contribute to long-term male reputation in groups, as females prefer mates that can reliably protect their offspring.

"Our observations on other forest guenons suggest that if males do not prove to be good group protectors, they likely have to leave groups earlier than good defenders," said study lead author Frederic Gnepa Mehon. 

"To date, it remains unclear whether female guenons have a saying in mate choice, but our current results strongly suggest this possibility."

During the study, a new type of call was consistently recorded named "kek." The experts found that the males used the "kek" call when exposed to a moving leopard model created by researchers for field experiments. 

Previous studies of putty-nosed monkeys in Nigeria never documented "keks," which indicates that putty-nosed monkeys have different dialects - a strong indicator of vocal production learning. 

According to the study authors, the findings advance our understanding of different female and male alarm calls. Males have more complex vocal ranges than females. However, the cognitive skills needed to effectively utilize simple female ranges are much more complex than those needed for male calling strategies. 

"Sexual selection might play a far more important role in the evolution of communication systems than previously thought," said study co-author Claudia Stephan.

"In a phylogenetic context, what strategies ultimately drove the evolution of communication in females and in males? Might there even be any parallels to female and male monkeys' different communication strategies in human language?"

The study is published in the journal <a href="https://royalsocietypublishing.org/journal/rsos">Royal Society Open Science</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Female monkeys use males as "hired guns" for protection

A team of researchers at the Wildlife Conservation Society (WCS)...

Coral species that appear to be identical to each other are turning out to be genetically distinct. This hidden diversity could be much more important for <a href="https://www.earth.com/news/bee-conservation-relies-on-plant-diversity/">conservation</a> than what was previously realized, according to researchers at the <a href="https://www.calacademy.org/">California Academy of Sciences</a>.

In collaboration with an international team of experts, the researchers are taking a new approach to studying hidden coral species by investigating their ecological differences, which have been largely overlooked. 

"We know we are greatly underestimating the true number of coral species because of this hidden diversity," said study lead author Pim Bongaerts. 

"In our study, we provide one of the first clear examples of how coral species that look identical can be very different in terms of their ecology and physiology, from when they reproduce to what depths they prefer. This means that our current framework for classifying reef-building corals based primarily on morphology is limiting our ability to understand and protect them."

The experts conducted one of the most extensive genomic studies of corals to date, including DNA samples from more than 1,400 individuals. The analysis showed that the serpent coral, one of the most widespread corals across the Indo-Pacific, is actually four different species that evolved millions of years ago. 

The researchers were stunned when they realized that the four species are indistinguishable from each other, even at a microscopic level. This prompted the team to look for ecological differences that may have been missed.

An investigation was launched using remotely-operated vehicles and specialized deep diving gear to analyze corals from shallow depths down to 80 meters beneath the surface. 

While individual corals from each species were spotted across the entire range, the experts discovered that each species had distinct depths where they were most abundant. In addition, there were differences in physiological traits, such as protein content, that affect each species' ability to survive and thrive at their preferred depths.

"Knowing what corals thrive where and at which depths is crucial for reef conservation," said study co-author Professor Ove Hoegh-Guldberg of the University of Queensland. 

"Most marine protected areas only protect shallow reefs, which means that hidden species at mesophotic depths are being overlooked by current conservation strategies. We need to give this gap in protection some further thought."

"For years we have asked ourselves about the relevance of this hidden diversity, wondering if we are missing something important," said study co-author Alejandra Hernández-Agreda. 

"By using all of the tools at our disposal to analyze not just the morphology, but all these other aspects of these species as well, we now show how this hidden diversity can mask major differences in these species that could translate to their ability to cope with the rapidly changing conditions of our world's oceans."

The researchers hope their findings reveal the importance of taking a holistic approach to understanding hidden coral species that are potentially harboring key differences which impact global conservation efforts.

"At a moment when reefs around the world are experiencing rapid degradation, it is critical to start capturing this hidden diversity - not only of species, but of how they live and function - to improve our understanding and ability to protect these fragile ecosystems," said Bongaerts.

The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The hidden diversity of coral species could help save them

Coral species that appear to be identical to each other...

A new report from the <a href="https://www.usgs.gov/">U.S. Geological Survey</a> has revealed that greater sage-grouse populations have declined dramatically over the last six decades. Across their range, the <a href="https://www.earth.com/news/migrating-seabirds-are-starving-and-eating-non-food-items/">birds</a> have declined by 80 percent since 1965 and by nearly 40 percent since 2002.

While the steady population reductions were found throughout the entire range, the rates of decline vary regionally.

The findings are based on the most comprehensive analysis of greater sage-grouse population trends to date. The study lays out a monitoring framework to assess those trends moving forward. 

Furthermore, the research can be used to evaluate the effectiveness of greater sage-grouse conservation efforts and to identify factors that contribute to habitat loss and changes in population sizes.

"Every day, the USGS brings diverse stakeholders the compelling science they need to make strategic, on-the-ground policy and management decisions," said David Applegate, associate director exercising the delegated authority of the USGS director. 

"With this framework in place, resource managers can more nimbly respond to population declines with actions such as redistributing monitoring efforts or prioritizing where management intervention may be needed."

The framework was developed to estimate greater sage-grouse population trends in 11 western states, including California, Colorado, Idaho, and Montana, where the birds can be found. The greater sage-grouse is considered to be an indicator species that signals the overall health of the iconic sagebrush ecosystem.

The researchers determined that the rate of greater sage-grouse decline has increased in western portions of the species' range, and the declines have been less severe in eastern areas. The only region with a relatively stable population is western Wyoming. 

Overall, the number of birds is now less than a quarter of what it was more than 50 years ago.

The team compiled information and created a rangewide database of greater sage-grouse breeding grounds. This data was used to analyze past and current population trends in different parts of the species' range.

The researchers also investigated the most threatened breeding grounds, and found the greatest risk at the periphery of the species' range. The experts report that there is only a 50 percent chance that most breeding grounds, called leks, will be productive in about 60 years from now if current conditions persist. 

"The framework we developed will help biologists and managers make timely decisions based on annual monitoring information," said study lead author Peter Coates. "This will allow them to address local issues before they have significant impacts on the population."

The study is published in the journal <a href="https://pubs.er.usgs.gov/browse/Report/USGS%20Numbered%20Series/Open-File%20Report/">USGS Open-File Report</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Greater sage-grouse populations have declined by 80 percent

A new report from the U.S. Geological Survey has revealed...

While many animals are seriously threatened by <a href="https://www.earth.com/news/warm-river-habitats-are-important-for-cold-water-fish/">habitat</a> loss, a new study from <a href="https://www.colostate.edu/">Colorado State University</a> reveals that African elephants do not fall into this category. The researchers found that African elephants only inhabit a small portion of their potential range.

The drastic reduction in range has been caused by an increasing human presence, as well the slaughtering of elephants for their ivory.

The study authors explained that due to 2,000 years of human pressure, African elephants have suffered dramatic population declines, and their range has shrunk to just 17 percent of what it could be.

If the threat of poaching was taken off the table, elephants could co-exist with humans to a much greater extent. The experts determined that 62 percent of Africa, which is over 18 million square kilometers, still contains suitable habitat for elephants. In some of this area, however, conflict with people could make it unrealistic.

The team analyzed data from GPS tracking devices and satellite imagery to investigate where elephants roam and why. 

Study lead author Dr. Jake Wall is the director of research and conservation at the Mara Elephant Project in Kenya. 

"We literally looked at every square kilometer of the continent," said Dr. Wall. "We found 62% of those 29.2 million square kilometers is suitable habitat."

The biggest areas of potential habitat include the Central African Republic and the Democratic Republic of Congo. The study also highlighted the extreme habitats that African elephants do not visit.

"The major no-go areas include the Sahara, Danakil, and Kalahari deserts, as well as urban centres and high mountaintops," said Iain Douglas-Hamilton, founder of Save the Elephants. 

"That gives us an idea of what the former range of elephants might have been. However, there's a dearth of information about the status of African elephants between the end of Roman times and the arrival of the first European colonizers."

The research was coordinated by Save the Elephants and included researchers from the Mara Elephant Project, the University of British Columbia, Oxford University, Colorado State University, the Wildlife Conservation Society, the University of Stirling, and Elephants Alive.

The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

African elephants only inhabit a small part of their potential range

While many animals are seriously threatened by habitat loss, a...

The unique skin adaptations of hippos and <a href="https://www.earth.com/news/grays-beaked-whales-have-been-stable-for-over-a-million-years/">whales</a> did not come from a common ancestor, according to a new study from the <a href="https://www.amnh.org/">American Museum of Natural History</a>. The researchers found that even though hippos and whales are close relatives, their nearly hairless skin evolved independently. 

"How mammals left terra firma and became fully aquatic is one of the most fascinating evolutionary stories, perhaps rivaled only by how animals traded water for land in the first place or by the evolution of flight," said study co-author John Gatesy. 

"Our latest findings contradict the current dogma in the field - that relatives of the amphibious hippo might have been part of the transition as mammals re-entered life in the water."

Fully aquatic cetaceans, including whales, dolphins, and porpoises, share a common ancestor that lived about 55 million years ago. They also share some characteristics that are not common among mammals, such as giving birth underwater and lacking most of their hair.

Since these traits are rarely found in other mammals, it would seem that they were already present in the common ancestor of hippos and cetaceans. 

The experts set out to determine whether hippos and cetaceans developed adaptations for an aquatic lifestyle independently, or if they inherited these traits from an amphibious ancestor.

"The simplest hypothesis is that the ancestor of whales and hippos was already amphibious, but evolution isn't always the shortest distance between two points," said study lead author Professor Mark Springer of UC Riverside.

To investigate, the researchers focused on the animals' skin, which changed dramatically in response to life in the water.

"When a group of animals becomes aquatic, skin becomes much more streamlined and uniform throughout," said study co-author Maksim Plikus. 

"Complex derivatives like hairs, nails, or sweat glands are no longer needed, and in fact, can become a hinderance to life under water, so those go away. And it loses the barrier function performed by the outer layer of skin, which in terrestrial mammals, is vital to keeping water from evaporating out of the body and preventing pathogens from getting in."

The researchers used genetic screening to compare the anatomy of hippo and cetacean skin, and assembled a list of "skin genes" that have been deactivated in both groups. The team also assembled the first genome sequence of the pygmy hippo, one of only two living hippo species.

"When you look at the molecular signatures, there is a striking and clear answer," said study co-author Michael Hiller. "Our results strongly support the idea that 'aquatic' skin traits found in both hippos and cetaceans evolved independently. And not only that, we can see that the gene losses in the hippo lineage happened much later than in the cetacean lineage."

The genetic differences are reflected in the skin itself. For example, cetaceans only have a few whiskers, while hippos are fully whiskered. 

In addition, hippos have a specialized sweat gland that whales do not possess. The sweat gland produces "blood sweat," an orange-colored substance that is believed to have natural antimicrobial and sunscreen properties. Furthermore, cetacean skin is much thicker than hippo skin.

"These differences are fully consistent with the record of evolutionary history that is written in their genomes, which shows the independent knockout of skin genes on the cetacean lineage and on the hippo evolutionary line," said Professor Springer. "None of the inactivating mutations that would have suggested a common aquatic ancestry are shared between these two lineages."

The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Hippos and whales evolved their hairless skin independently

The unique skin adaptations of hippos and whales did not...

The cost of invasive species to human society totaled at least $1.28 trillion from 1970 to 2017, and the damage is tripling every decade, according to researchers at <a href="https://www.flinders.edu.au/">Flinders University</a>. The experts report that in 2017 alone, the cost of invasive species hit $162.7 billion.

Invasive species have damaged crop yields, critical national infrastructure, and human health. However, these damages are not sufficiently recognized by policy makers or the public. 

The researchers analyzed thousands of cost estimates to calculate the annual economic losses tied to invasive species. These annual costs are expected to rise into the trillions in the coming years due to the increasing frequency of biological invasions.

Study lead author Dr. Christophe Diagne is an invasion ecologist at the University Paris-Saclay. He said that his team has created a reliable, standardized catalog of the economic costs caused by biological invasions to help clarify the importance of effective management policies going forward.

"This trillion-dollar bill doesn't show any sign of slowing down, with a consistent threefold increase per decade," said Dr. Diagne.

"Our annual global estimates signify the huge economic burden, with the average cost exceeding the gross domestic product of 50 countries on the African continent in 2017, and it's more than 20 times higher than the total funds available for the World Health Organization and UN combined."

Professor Corey Bradshaw noted that biological invasions are increasingly exacerbated by globalization and climate change, but no government is prepared to manage the crisis without substantial costs. "We found that costs roughly doubled every 6 years, a pattern that mimics the continuous increase in the number of alien species worldwide."

Despite the enormous impacts associated with biological invasions, the public remains largely unaware of these threats. For example, invasive species are the second biggest driver of extinctions.

"The global costs of invasive alien species are so massive that we spent months verifying our models and this overall estimate, to insure we were not exaggerating," said Dr. Diagne. "As it turns out, our very conservative approach is in fact a massive underestimation of the actual economic costs".

"The trend can be explained by a combination of factors: the ongoing intensification of global trade and transport creates many more opportunities for invasions; the growing 'land take' of the planet surface, for example, expansion of agriculture and infrastructure, makes our societies sensitive to impacts from these invasions."

The researchers warn that the costs in both developed and developing economies are soaring, and will continue to do so unless governments coordinate effective international policies to reduce the risks. 

"That's why we're calling for international policy agreements that aim to reduce the burden of invasive species," said Professor Bradshaw.

The study is published in the journal <a href="https://www.nature.com/">Nature</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Invasive species have racked up more than $1.28 trillion in damages

The cost of invasive species to human society totaled at...

A new study from the <a href="https://www.ubc.ca/">University of British Columbia</a> reveals that tilapias do not die in stressful conditions like most <a href="https://www.earth.com/news/warm-river-habitats-are-important-for-cold-water-fish/">fish</a>. Instead, these resilient animals survive in rough environments by stunting their growth and carrying on with their lives in dwarf form.

In stressful environments like crowded aquaculture ponds, tilapias adapt so well that they stop growing and reproduce at a smaller size.

"Tilapia and other fish in the Cichlidae family do not spawn 'earlier' than other fishes, as it is commonly believed. Rather, they are uncommonly tolerant of stressful environmental conditions which, however, elevate their oxygen demand," explained study lead author Upali S. Amarasinghe of the University of Kelaniya.

Just like all fish, tilapias need more oxygen to sustain bodily functions when their metabolism increases. However, the gills eventually reach a point where they cannot supply enough oxygen for a larger body, so the fish either dies or just stops growing.

Study co-author Daniel Pauly is the principal investigator of the Sea Around Us initiative at UBC's Institute for the Oceans and Fisheries. 

"Gill surface area grows in two dimensions, that is, length and width, but they cannot keep up with bodies that grow in three dimensions - length, width and depth," said Pauly.

"As fish get bigger, their gills provide less oxygen per unit of body weight. Thus, to stay alive in stressful conditions, which increase their oxygen demand, fish have to remain smaller. This theme is further developed in what I called the Gill Oxygen Limitation Theory."

For tilapias, the stress they experience in their environment is compounded by the stress of their gills not keeping with the increasing oxygen demand of their growing bodies. The subsequent cascade of hormones triggers maturation and spawning at smaller sizes than what would occur under optimal conditions.

The experts noted that the spawning does not simply occur at a younger age, as the fish's growth process has already ended.

For their investigation, the researchers analyzed the maximum lengths reached among nine different fish species, including tilapia and other cichlids, in lakes and aquaculture ponds across the world. Overall, the team studied 41 populations of fish in places like Brazil, Uganda, Egypt, and Hong Kong.

When they looked at the ratio between the maximum lengths these fishes can reach and their lengths when they reproduce for the first time, they found it was the same for tilapias that has been previously identified in other fish.

"This ratio tells us that tilapias in stressful conditions don't spawn 'earlier,' they just adjust their size downward, but their life cycle continues," said Amarasinghe.

"These findings will matter to fish farmers, notably in Asia, whose ponds are often full of wildly reproducing, small tilapia for which there is no market," noted Pauly.

The study is published in the journal <a href="https://www.asianfisheriessociety.org/publication/">Asian Fisheries Science</a>. 

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Tilapias stunt their own growth to survive stressful conditions

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

Researchers at the <a href="https://www.exeter.ac.uk/">University of Exeter</a> propose that having friends and enemies makes evolutionary sense among the <a href="https://www.earth.com/news/faking-death-is-a-good-way-for-animals-to-stay-alive/">animals</a> that age slowly and live for many years. The scientists argue that natural selection favors complex social structures and relationships in long-lived animals. 

Animals that live fast and die young focus their energy on reproduction, while animals that age much more slowly invest in survival and live longer lives.

For long-lived animals, knowing their friends and enemies comes more easily, and helps them to live even longer. Animals that live and die at a fast pace, however, should only bother with social relationships if it increases their chances of reproduction, explained the researchers.

"Slow-living species can afford to invest in social relationships, as they live long enough to enjoy the pay-offs," said Professor Dave Hodgson. "There is strong evidence that strong social bonds are beneficial for survival in slow-living species, including humans."

"We suggest there is a 'positive feedback' - certain social behaviours lead to a longer life, and longer lifespan promotes the development of social bonds."

Professor Hodgson said there is growing evidence that differentiated social relationships have a stronger supportive effect on survival than on reproduction. As a result, fast-lived species do not gain the same evolutionary advantages from social relationships as long-lived species.

"If we want to understand more about social relationships and lifespan, we need to think about the relationship between the two," said Dr. Matthew Silk. He noted that further research is needed to explore the social structures of wild animals, and could help to clarify the links between social bonds, survival and reproduction.

"Our proposal, that strong and weak social bonds will be more prevalent in slower-living animals, is theoretical," said Professor Hodgson. "We know a lot about animal lifespans, but we know too little about the social structures of many types of animal. If we are right, then social bonds could really be key to longer life."

The study is published in the journal <a href="https://www.cell.com/trends/ecology-evolution/home">Trends in Ecology and Evolution</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Social bonds are more advantageous for long-lived animals

Researchers at the University of Exeter propose that having friends...

Coral reefs may rely on poop from their predators, according to a surprising new study from <a href="https://www.rice.edu/">Rice University</a>. The revelation was made in the lab of marine biologist Adrienne Correa, where researchers discovered that coral predator feces are packed with living symbiotic algae that corals depend on for survival. 

It's an unexpected twist on coral reef symbiosis, said Correa. The study confirms that poop from coral-eating fish is an important source of symbiotic dinoflagellate algae for corals.

Correa explained that coral-eating predators are typically thought of as biting and weakening reef structures, thereby generating hiding spaces for other organisms and, ultimately, beach sand. By contrast, grazing fish take the credit for helping reefs maintain healthy coral cover.

"The message is, 'Move over grazers, it's not just you helping maintain coral dominance. These coral-eating fishes are probably helping too by spreading beneficial coral symbionts,'" said Correa.

"This tells us we don't really know all of the interactions that are happening on coral reefs, and some species may be important for coral reef conservation in ways that we haven't imagined," said study lead author Carsten Grupstra.

During an expedition to the island of Mo'orea in French Polynesia, the researchers followed fish that ate different amounts of coral and algae. The team documented what the fish ate and where they defecated. Meanwhile, Grupstra gathered samples of predator and grazer poop to examine in the lab.

"I left some samples in the window sill for a couple of weeks in Mo'orea," said Grupstra. "Later, when I started looking at them (under a microscope), I found tons of symbionts. A lot of them were swimming around and some were dividing."

The sheer number of live symbionts was both unexpected and potentially important in the larger picture of reef ecology, said Correa. 

Symbionts have been previously found in the feces of some coral predators, but it has remained unclear if they were useful to corals. The Rice team has now discovered high concentrations of live symbionts in the feces of a diverse group of coral predators. 

The researchers estimate that two species in particular, Chaetodon ornatissimus and Chaetodon reticulatus, each spread about 100 million live symbionts per day over an area of reef approximately the size of six parking spaces.

"This expands how we can think about the roles of coral-eating fishes on reefs," said Correa. "They don't just break up reef frameworks. They also disperse symbionts that corals and other organisms need."

The discovery that predator poop creates hotspots of live symbiotic dinoflagellates on reefs raises questions about whether and how coral use them. 

Going forward, Correa's team will conduct a series of experiments on corals to determine how readily they absorb beneficial symbionts from the poop. She said many questions remain about how corals take up symbionts from the environment. 

The study is published in the journal <a href="https://animalmicrobiome.biomedcentral.com/">Animal Microbiome</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Do corals depend on poop from their predators?

Coral reefs may rely on poop from their predators, according...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"]</div>



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



---



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

[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"] Today’s Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"]</div>



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;



---



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

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="3upvlAaHgO-2256633-12187" type="single"]</div>



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;



---



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

[sendtonews key="3upvlAaHgO-2256633-12187" type="single"] Today’s Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"]</div>



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;



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="X0f6OHYoI4-2310561-12187" type="single"]</div>



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



---



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?

[sendtonews key="X0f6OHYoI4-2310561-12187" type="single"] Today’s Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="JRaP49ISmm-2357509-12187" type="single"]</div>



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



---



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

<div class="wp-block-sendtonews-playerselector">[sendtonews key="e4ZG0Jawp3-2374785-12187" type="single"]</div>



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;



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="uV9Lh2fQbV-1760058-12187" type="single"]</div>



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;



---



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"

[sendtonews key="uV9Lh2fQbV-1760058-12187" type="single"] Lesotho: Africa's "Kingdom in the Sky" Today’s...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="qjvhBOBnY8-2426650-12187" type="single"]</div>



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;



---



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

[sendtonews key="qjvhBOBnY8-2426650-12187" type="single"] Today's Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="oL4FnPTGCV-2384527-12187" type="single"]</div>



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



---



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

[sendtonews key="oL4FnPTGCV-2384527-12187" type="single"] Today's Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="0879czfG3k-1785905-12187" type="single"]</div>



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



---



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

[sendtonews key="0879czfG3k-1785905-12187" type="single"] Today’s Video of the Day from NASA...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="6HyfrAJTBI-1831843-12187" type="single"]</div>



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



---



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

<div class="wp-block-sendtonews-playerselector">[sendtonews key="QIoVYJqRBi-2434608-12187" type="single"]</div>



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)



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="JbW4VsY53O-1632195-12187" type="single"]</div>



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;



---



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



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="qARzJPSabQ-2270617-12187" type="single"]</div>



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;



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="qas3EhyI0Y-2220951-12187" type="single"]</div>



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



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="vpljfR2VBX-2560867-12187" type="single"]</div>



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



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="MHyhtebibJ-2200368-12187" type="single"]</div>



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;



---



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...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="761m2QQvR1-2035772-12187" type="single"]</div>



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;



---



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...