For centuries, humans have shaped the traits of domesticated animals to meet their needs. From larger cows producing more milk to dogs bred for specific temperaments, selective breeding has transformed species in remarkable ways. Recent research on German pigs has revealed just how quickly these changes can occur.



A team from Martin Luther University Halle-Wittenberg (<a href="https://www.uni-halle.de/?lang=en" target="_blank" rel="noreferrer noopener">MLU</a>) has found that German domestic pigs have experienced dramatic skull modifications within a century. 



Their snouts have shortened, and their foreheads have flattened, traits that were not intentionally selected. The findings provide fresh insight into the unintended <a href="https://www.earth.com/news/old-and-wise-animals-are-essential-for-the-survival-of-species/" target="_blank" rel="noreferrer noopener">consequences</a> of breeding practices.



<h2 class="wp-block-heading" id="h-a-century-of-change-in-pig-breeding">A century of change in pig breeding</h2>



Pigs have been an essential part of human agriculture for thousands of years. Over time, their appearance has shifted significantly, influenced by both natural and human-driven factors. 



In Germany, the early 20th century marked a turning point in pig breeding, as demand for pork increased dramatically. Farmers prioritized traits such as rapid growth, high fertility, and efficient meat production.



"The demand for pork in Germany increased significantly at the beginning of the 20th century, and breeders were encouraged to optimize their animals. They needed them to grow quickly, provide good meat, and be fertile," explained Dr. Renate Schafberg, Head of the Domestic Animal Collection at MLU.



To understand the impact of these breeding efforts, Dr. Schafberg worked with Dr. Ashleigh Haruda from Oxford University to analyze 135 pig skulls from different time periods.



The study included two domestic breeds - Deutsches Edelschwein and Deutsches Landschwein - as well as wild boars, which served as a control group. The results revealed a striking transformation in domestic pigs, while wild boars showed no comparable changes.



<h2 class="wp-block-heading" id="h-surprising-skull-modifications">Surprising skull modifications</h2>



One of the most significant findings of the study was the extent of skull changes in domesticated pigs. Their snouts became notably shorter, and their foreheads lost their outward curve. These modifications occurred in both domestic breeds, despite the fact that they were raised separately.



"We didn’t expect such pronounced differences to appear within a span of only 100 years," said Dr. Schafberg. The fact that both breeds experienced similar changes suggests that the modifications were not the result of direct selection for skull shape.



"These changes occurred even though breeders did not select the animals specifically for their skull shape, as this trait was not important for breeding. Instead, the changes appear to be an unintended by-product of selecting the desired traits," noted Dr. Schafberg.



This discovery highlights how the pursuit of specific breeding goals can lead to unforeseen alterations in an <a href="https://www.earth.com/news/what-animal-will-replace-humans-as-earths-dominant-species-this-scientist-has-an-idea/" target="_blank" rel="noreferrer noopener">animal</a>’s physical structure.



<h2 class="wp-block-heading" id="h-could-diet-play-a-role">Could diet play a role?</h2>



While breeding practices played a major role in shaping the skulls of domestic pigs, another factor may have contributed: diet. 



Nutrition is a key influence on the <a href="https://www.earth.com/news/sheep-have-been-intertwined-with-humans-for-over-11000-years/" target="_blank" rel="noreferrer noopener">growth and development</a> of animals. Modern pigs are primarily fed high-protein pellets designed to support rapid growth and efficient meat production.



By contrast, wild boars continue to consume a varied diet, including roots, nuts, and small animals. Their skulls have remained unchanged over the past century, suggesting that their natural feeding habits have helped maintain their original features. 



The study raises intriguing questions about the relationship between diet and physical evolution in domesticated animals.



<h2 class="wp-block-heading" id="h-power-of-human-influence">Power of human influence</h2>



The findings demonstrate the remarkable speed at which human intervention can shape animal species. While many assume that significant evolutionary changes take millions of years, selective breeding can accelerate these processes dramatically.



"Charles Darwin assumed that long periods of time - millions of years - are required for major changes to take place. Our work is further proof that humans can greatly accelerate this process through selective breeding," said co-author Dr. Frank Steinheimer, Head of the Central Repository of Natural Science Collections at MLU.



These insights have broader implications for agriculture and animal husbandry. As selective breeding continues to shape domesticated animals, researchers must consider the potential consequences, both intended and unintended. 



The study serves as a reminder that even small changes in breeding practices can have <a href="https://www.earth.com/news/birds-are-moving-north-and-breeding-earlier-in-a-changing-climate/" target="_blank" rel="noreferrer noopener">lasting effects</a> on animal physiology.



<h2 class="wp-block-heading" id="h-pig-breeding-may-continue-in-the-future">Pig breeding may continue in the future</h2>



As the global demand for meat continues to grow, breeding practices will likely continue to evolve. Understanding how these methods impact animal development is crucial for ensuring sustainable and ethical farming. 



Scientists will need to explore the long-term effects of breeding choices, considering not only productivity but also the health and well-being of animals.



The study was funded by the German Federal Ministry of Education and Research (<a href="https://www.bmbf.de/EN/Home/home_node.html" target="_blank" rel="noreferrer noopener">BMBF</a>) and the European Research Council (<a href="https://erc.europa.eu/homepage" target="_blank" rel="noreferrer noopener">ERC</a>). 



The research offers a compelling look at the complex relationship between human influence and animal evolution, shedding light on the ways in which farming practices shape the very biology of domesticated <a href="https://www.earth.com/news/world-wildlife-conservation-day-2024-saving-species-from-extinction/" target="_blank" rel="noreferrer noopener">species</a>.



The study is published in the journal <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.241039" target="_blank" rel="noreferrer noopener">Royal Society Open Science</a>.



-----



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Selective breeding has dramatically sped up the evolution of pigs

For centuries, humans have shaped the traits of domesticated animals to meet their needs. From larger cows producing more milk to dogs bred for specific temperaments, selective breeding has transformed species in remarkable ways. Recent research on German pigs has revealed just how quickly these changes can occur. A team from Martin Luther University Halle-Wittenberg (MLU) has found that German domestic pigs have experienced dramatic skull modifications within a century. Their snouts have shortened, and their foreheads have flattened, traits that were not intentionally selected. The findings...

Scientists estimate that the <a href="http://www.earth.com/news/taller-older-rainforests-drought/">Amazon rainforest</a> is home to one-third of the world's plants and animals, but with so many species yet to discover, this could be an understatement. Experts at Chicago's <a href="https://www.fieldmuseum.org/">Field Museum</a> are describing six previously unknown species of catfish that can be distinguished by a face covered in tentacles. 

Study lead author Lesley de Souza is a conservation scientist and ichthyologist at the museum. 

“We discovered six new species of really cool catfish from the Amazon and Orinoco River basins,” said de Souza. “They have tentacles on their snouts, they have spines that stick out from their heads, almost like claws, to protect themselves and their nests, and their body is covered with bony plates like armor. They're warriors, they're fish superheroes.”

The catfish are all members of the genus Ancistrus, or bristlenose catfish. At the aquarium, these are the sucker-mouthed “algae-eaters” that help clean the tanks. 

The fish are between three and six inches long, and the males have tentacles covering their snouts, which help them stand out to potential mates. Ancistrus catfish fathers are responsible for guarding nests of eggs and protecting them from predators, and the tentacles make them appear qualified for the job. 

“The idea is that when a female fish sees a male with these tentacles, to her, they look like eggs. That signifies to her that he's a good father who's able to produce offspring and protect them,” explained de Souza.

The catfish can be found in northeastern South America in clear, fast-moving rivers and streams. 

“If you're in the right habitat, you're going to find a lot of them,” said de Souza. “But they are sensitive to subtle changes in the environment, we have seen this at sites where they were plentiful and now scarce, this is due to habitat destruction.”

[caption id="attachment_1867344" align="aligncenter" width="700"]<a href="https://www.earth.com/wp-content/uploads/2019/02/catfish.jpg"><img class="wp-image-1867344" src="https://www.earth.com/wp-content/uploads/2019/02/catfish.jpg" alt="" width="700" height="262" /></a> Image Credit: Jonathan W. Armbruster[/caption]

Some of the biggest threats are large-scale agriculture, deforestation, and gold mining. 

“Miners dredge up the river bottom causing increased sediment load, this changes the habitat structure of the river system, thus impacting the fishes ability to survive,” said de Souza. “Another effect from gold mining is the use of mercury to extract the gold in the river. This impacts all wildlife and principally local people that consume these fishes and other species in the watershed.”

“The whole ecosystem is interconnected - you can't separate the species in it. Giant river otters love to eat these catfish, and jaguars have been observed to have higher mercury levels from eating contaminated fish or other species that feed on fish. This can have dire impacts on the whole ecosystem. All the layers of the Amazon basin are interconnected from the rivers to the forest canopy.”

According to de Souza, the process of saving the Amazon starts with discovering new species and giving them names. With so many potentially unknown species remaining in the Amazon, the work will continue. 

“I have this undying curiosity - what's around that bend, that corner, what's in that creek, what can I find? And this project was all about discovery, whether we were finding new species in rivers in Guyana or in jars in museum collections. This study included more than 500 specimens, but this is just a drop in the bucket - there's still so much more to learn about Ancistrus and other Neotropical fish.”

The study is published in the journal <a href="https://www.mapress.com/zootaxa/">Zootaxa</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Six new strange-looking catfish species discovered in South America

Scientists estimate that the Amazon rainforest is home to one-third...

One of the oldest cases of bone cancer was recently discovered in a 240-million-year-old shell-less stem-turtle fossil known as Pappochelys rosinae, proving that cancer has been around long before humans.

The turtle lived during the middle <a href="https://www.earth.com/news/life-triassic-period/">Triassic</a> when dinosaurs first began to appear, and the species is an integral part of the modern-day turtle’s evolutionary history. 

A fossil of Pappochelys rosinae, first discovered in 2013 and kept in the <a href="https://www.naturkundemuseum-bw.de/intl/englisch/stuttgart-state-museum-natural-history">Stuttgart State Museum of Natural History</a>, had a mysterious growth on its back leg bone. 

Researchers from the <a href="https://www.museumfuernaturkunde.berlin/en">Natural History Museum in Berlin</a> studied the bone growth and found that it was a malignant and aggressive tumor.

“This is one of the oldest cases of cancer in the fossil record of vertebrates, and the oldest case in an amniote, which is the group that encompasses reptiles, birds and mammals,” said Florian Witzmann, an author of a study detailing the bone cancer.

[caption id="attachment_1867422" align="aligncenter" width="700"]<a href="https://www.earth.com/wp-content/uploads/2019/02/Ancient-turtle-fossil-proves-that-cancer-long-predates-humans-copy.jpg"><img class="wp-image-1867422" src="https://www.earth.com/wp-content/uploads/2019/02/Ancient-turtle-fossil-proves-that-cancer-long-predates-humans-copy.jpg" alt="" width="700" height="471" /></a> Image Credit: Rainer Schoch/Wikimedia[/caption]

The study, published in the Journal of the American Medical Association Oncology, highlights the importance of paleopathology which is the study of ancient diseases.

This recent finding is particularly noteworthy because it’s difficult to find cancers in early fossils.

“Generally, paleopathologies are rare in fossils, particularly malignant cancers which are almost unheard of in the fossil record, making this a rare find indeed,” said Patrick Asbach, a co-author of the study.

The researchers scanned the turtle fossil and examined the growth under a microscope to help identify the tumor, which was located in the back of the left leg toward the hip joint.

The earliest case of bone cancer in humans was found in the bone of an ancient human ancestor that died in South Africa between 1.6 and 1.8 million years ago.

[caption id="attachment_1867423" align="aligncenter" width="634"]<a href="https://www.earth.com/wp-content/uploads/2019/02/turtle.jpg"><img class="size-full wp-image-1867423" src="https://www.earth.com/wp-content/uploads/2019/02/turtle.jpg" alt="" width="634" height="777" /></a> Image Credit: JAMA Oncology[/caption]

Because there are so few cases of cancer that pop up in the fossil record, researchers know very little about the disease’s origins, and there has long been an assumption that cancer is a modern malady.

“Our finding provides further evidence that cancer is not restricted to the modern human physiology. Instead, the susceptibility to this disease roots far back in the evolutionary history of vertebrates, hundreds of millions of years before the origin of humans,” said Yara Haridy, the first author of the study.

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com </a>Staff Writer 

Main Image Credit: Rainer Schoch/Wikimedia

Ancient turtle fossil proves that cancer long predates humans

One of the oldest cases of bone cancer was recently...

New research published by <a href="https://www.unl.edu/">University of Nebraska-Lincoln</a> shows that in Earth’s largest mass extinction, plants were likely killed off before animals started to wink out.  While this pattern of death is somewhat intuitive, it has real implications to our lives today.

About 252 million years ago, 70% of land vertebrates like you and me died off.  Along with animals living on land, 96% of ocean life also died off. The cause of the extinction seems to be from massive volcanic eruptions in what is now modern Siberia triggered by collision of tectonic plates.  

The volcanic eruptions threw ash and other pollutants into the air, creating a global cooling event, similar to a hypothetical nuclear winter.  Nickel from the eruption in particular may have killed off plants now fossilized in Australia 400,000 years before most of the marine extinctions occurred.  Scientists with University of Nebraska-Lincoln have been studying pollen fossils in the sea cliffs of Australia’s Sydney Basin where high levels of nickel have been found associated with pollen.  The scientists hypothesize that the nickel was turned into an aerosol by the volcanic eruptions in Siberia, and rained down on plant life, poisoning it and kicking off the mass extinction event. Unexpectedly high levels of nickel have been recorded in other parts of the world as well.    

The extinction, commonly called the <a href="http://www.earth.com/news/permian-mass-extinction/">end Permian extinction event</a>, came along at a time of great change in the history of life on Earth.  In the Permian oceans, there was a rich diversity of shellfish. There were cephalopods that looked much like the modern nautilus with coiled snail-like shells enclosing bodies more like squids.  On land, enormous primitive dragonflies were fearsome predators. Mammals were just on the verge of evolving from reptiles. The whole planet was alien to modern eyes but full of an abundance of wildlife.  Plants of the time were mainly ‘primitive’; flowering plants not having evolved yet. Still the primitive forms supported entire ecosystems and filled niches later occupied by more ‘advanced’ forms. Ferns, mosses, gymnosperms and equisetum are a few examples of the plants that dominated the Permian landscape.      

If nickel did indeed kill off large amounts of plants, it’s easy to see how this would devastate whole ecosystems.  When there are no plants, herbivores starve and die. When there are no herbivores, carnivores starve and die. It’s a pretty straightforward connection between the extinction of plants and the extinction of animals.

An earlier paper in <a href="https://www.sciencedirect.com/science/article/pii/S0921818110002286">Global and Planetary Change</a> discusses how plant composition changed at the extinction at the end of the Permian.  Before the end Permian extinction event, gymnosperms seem to be the most prevalent plants.  Gymnosperms are best represented today by conifers such as pine trees, that is plants bearing cones are gymnosperms as opposed to flowered plants.  Gymnosperms are more often pollinated by wind than insects like flowering plants. After the end Permian extinction event, there is a shift from a dominance of gymnosperms in the fossil record to a dominance of lycopods.  Lycopods are plants much more easily missed than gymnosperms. Commonly known as ground pines or creeping cedars, lycopods reproduce via spores, similar to ferns. Lycopods are small and inconspicuous for the most part, looking a little like mosses with small cones that bear their spores sticking above the soil.

Interestingly, the shift from gymnosperm dominance to that of lycopods was relatively short-lived.  Despite plants being the first to die off, they also seem to be some of the first organisms to rebound from the massive extinction.  All major plant groups ended up surviving the end Permian extinction and helps to explain the lesser extent to which land animals died off when compared to marine organisms.  Perhaps even more interestingly, the turnover of different plant regimes and the rebound of plant diversity are linked to carbon in the atmosphere. 

A study published in <a href="http://science.sciencemag.org/content/362/6419/eaat1327">Science</a> suggests that indeed, it was carbon and related ocean warming that drove the extinction of marine species.  The research shows that oceans at the end of the Permian rose in temperature by a staggering 20°F, and caused the loss of 80% of the ocean’s oxygen.  This change in temperature and dissolved gases obviously had devastating effects on life. In the long run, we can say that the oceans ‘recovered’ meaning that an abundance of new species evolved and again filled the waters with life.  In another view, something was lost forever. Individual species lost are lost forever but diversity can again recovery over extremely long periods of time. It’s easy to think of it like this – an individual child may die and the parents of that child might have three more.  We can say that on some level the family recovered from the loss of the child but we know on another level, they will never be the same.

An article in <a href="https://www.forbes.com/sites/priyashukla/2018/12/10/what-we-can-learn-from-a-252-million-year-old-ocean-extinction/#535a08f4706e">Forbes</a> asks, ‘What can we learn’ from the Permian extinction?  As we are in a new age of mass extinction, partially caused by carbon emissions, there is a lot we can learn.  One disturbing takeaway is that ocean life may suffer more from climate change than terrestrial biota. Another lesson is that plant life is of utmost importance to the resilience and survival of terrestrial biodiversity.  It’s disturbing that along with carbon emissions, humans are also destroying millions of acres of forests. We’re also massively altering plant communities with agriculture. Sadly, we can only learn so much from the end Permian extinction because it happened at a much slower pace than our current extinction event.  The Permian event was on a scale of millions of years, now we’re working on a scale of hundreds or thousands of years. Beyond climate, habitat destruction, resource overuse, overhunting, and many more human created problems are driving our current extinction event. Only time will tell if plants can lead another rebound in diversity of life once humans are done wreaking destruction.      

--

By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="http://earth.com">Earth.com</a> Contributing Writer

The plants go first: Lessons from Earth’s largest mass extinction

New research published by University of Nebraska-Lincoln shows that in...

Scientists have discovered a relative of the <a href="http://www.earth.com/news/black-widow-spiders-strong-silk/">Black Widow spider</a> in South Africa. The Phinda Button spider is the first new widow species to be described in 28 years, and may also be the largest of the poisonous widow spiders. 

Barbara Wright, an entomologist at the <a href="https://www.wildtomorrowfund.org/">Wild Tomorrow Fund</a>, initially found the spider in 2014 at Tembe Elephant Park. The experts speculate that the bite of the Phinda Button spider is comparable that of the Black Widow, which is considered to be the most venomous in North America. 

“Although we still haven't done the toxicology on this species, all widow spiders (genus Latrodectus) are considered medically important due to their potent neurotoxic venom,” said Wright. “The effects of the venom on human beings may include pain, palpitation, sweating and vomiting.”

“Previously-discovered species of widow spider make up three of the world's nine deadliest spiders, as listed by the Encyclopædia Britannica. Yet in truth, Latrodectus bites rarely result in death - and the same will likely be true of the new species.”

According to Dr. Ian Engelbrecht, an arachnid expert at the <a href="https://www.up.ac.za/">University of Pretoria</a>, the Phinda Button is native to the critically-endangered sand forests of South Africa. The females have distinctive bright red marks on both their back and underbelly. The spider can also be distinguished by its purple-colored egg sac, which holds hundreds of hatchlings.

According to Wright, the species is extremely shy, reclusive, and docile. She noted that there have been no reports of bites from them. While it has not yet been determined whether it is the largest widow spider in the world, Dr. Engelbrecht said it is “certainly the largest in Africa.”

“I immediately thought this was something special but I was uncertain if it was just some specimen that blew in from Madagascar or some other exotic place.”

[caption id="attachment_1867342" align="aligncenter" width="548"]<a href="https://www.earth.com/wp-content/uploads/2019/02/spider.jpg"><img class="size-full wp-image-1867342" src="https://www.earth.com/wp-content/uploads/2019/02/spider.jpg" alt="" width="548" height="368" /></a> Image Credit: Pen News/Luke Verburgt[/caption]

Dr. Engelbrecht helped Wright confirm that the Phinda Button is a new species.

“When Barbara showed me the first photo, I literally could not believe this spider existed and that it was unknown to science. Discovering a new species is always exciting, but the feeling of finding something so spectacular and unique is indescribable,” said Dr. Engelbrecht. “Widow and button spiders are medically important for humans, so it's important to understand their diversity.”
--
By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer
Main Image Credit: Pen News/Luke Verburgt

New species of widow spider may be the largest of its kind

Scientists have discovered a relative of the Black Widow spider...

Aedes aegypti

Suppressing mosquito appetites could persuade them not to bite. New research from scientists at the <a href="https://www.rockefeller.edu/our-scientists/heads-of-laboratories/913-leslie-b-vosshall/">lab of Leslie B. Vosshall</a> from <a href="https://www.rockefeller.edu/">The Rockefeller University</a> reveals it may be possible shut down the host-seeking and blood-feeding behaviors of female mosquitoes. Their findings, published February 7th in the journal <a href="https://www.cell.com/">Cell</a>, could result in mosquitoes being rendered harmless creatures in the future.

Scientists experimented on the Aedes aegypti mosquito, the species of mosquito responsible for spreading life-threatening diseases like Zika, chikungunya, yellow fever, and dengue. Female Aedes feed on human beings because our blood possesses protein needed for the Aedes to produce her eggs. After they feed and become bloated, they do not seek blood for several days.

This bloated phenomenon can be recreated by scientists injecting female <a href="http://www.earth.com/news/malarial-mosquitoes-cattle-decoys/">mosquitoes</a> with large doses of neuropeptides, which activate certain receptors. Laura Duvall, the postdoctoral fellow project leader, and her team were able to figure out which neuropeptide compound would work to suppress the mosquitos’ appetite — by studying similar receptors in our own human bodies. 

Duvall and her team found that anti-obesity drugs used to inhibit Neuropeptide Y or NPY receptors in humans — those being receptors that regulate food intake — could affect NPY-like receptors in mosquitoes as well.

"We were impressed and amazed that drugs designed to affect human appetite worked perfectly to suppress mosquito appetite," said Vosshall, Rockefeller’s Robin Chemers Neustein Professor.

After a series of neuropeptide cloning tests, the team found that the drug was affecting the mosquito NPY-like receptor known as NPYLR7.

Because this human drug could not be safely introduced into the wild, the team then searched for molecules that would activate NPYLR7 without triggering human NPY receptors. They narrowed down a list of 250,000 candidates to one molecule — compound 18, the molecule that suppressed Aedes' host-seeking behavior without showing off-target effects.Mosquitoes who were fed compound 18 didn’t hunt for human blood, nor other mammal’s blood. 

The next step is to find where the receptor is located within the mosquitoes’ bodies to help stop the spread of mosquito-transmitted diseases. And perhaps, compound 18 could be delivered to female mosquitoes in the wild to thwart disease before new disease-carrying mosquitoes are born.

--

By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Suppressing mosquito appetites could persuade them not to bite

Suppressing mosquito appetites could persuade them not to bite. New...

When fish swim up to the glass, do they recognize their own reflection? Are fish self-aware?

A new study conducted by researchers from the <a href="https://www.orn.mpg.de/en">Max Planck Institute for Ornithology</a> and <a href="https://www.osaka-cu.ac.jp/en">Osaka City University</a> says yes and no, as the results beg a broader question of what constitutes “awareness” in different species. 

The study was published in the journal <a href="http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3000021">PLOS Biology</a>, and the researchers focused on the cleaner wrasse (Labroides dimidiatus) fish to better understand self-awareness, a cognitive trait that <a href="https://www.earth.com/news/elephants-body-conscious/">few animals are thought to possess</a>. 

When the fish saw themselves in the mirror, the researchers observed behavior that seemed to suggest self-awareness, and the fish “passed” the mark mirror test which is used to test awareness in animals like primates. 

However, the researchers are cautious to compare the wrasse’s passing marks to the self-awareness of other animals, and the study results are more complicated than a black and white definition of self-awareness and recognition.  

The results do show that the fish are far more intelligent than previously given credit for. 

“The behaviours we observe leave little doubt that this fish behaviourally fulfils all criteria of the mirror test as originally laid out,” said Alex Jordan, the senior author of the study. “What is less clear is whether these behaviours should be considered as evidence that fish are self-aware--even though in the past these same behaviours have been interpreted as self-awareness in so many other animals.” 

Mirror self-recognition, or the ability to recognize one’s reflection for what it is, is an essential marker of awareness and cognition in animals. With the cleaner wrasse, a mirror mark test is more challenging. 

Researchers usually consider the mark mirror test “passed” if an animal recognizes a foreign mark on its reflection and tries to investigate or remove it, but fish don't have limbs. 

For this study, the researchers placed a colored mark on a cleaner wrasse and waited to see how it reacted to its reflection. The fish tried to remove the mark after seeing themselves in the mirror by scraping their bodies on different surfaces which the researchers saw as self-aware behavior. 

The fish didn’t try to remove transparent marks, and they didn’t remove marks if they never saw their reflection. 

The fish also didn’t attempt to remove a mark on themselves if they saw another fish had one which means that the wrasse understood the difference between another fish and its reflection. 

However, what exactly this means for fish awareness is unclear, according to the study. 

“Depending on your position, you might reject the interpretation that these behaviours in a fish satisfy passing the test at all,” Jordan said. “But on what objective basis can you do this when the behaviours they show are so functionally similar to those of other species that have passed the test?”

In a companion commentary to the study, Frans de Waas, a primatologist at <a href="http://www.emory.edu/home/index.html">Emory</a>, is also quick to point out that self-awareness for fish probably doesn’t mean the same thing that it does for humans or other species. 

‘What if self-awareness develops like an onion, building layer upon layer, rather than appearing all at once?” said Waal. “To explore self-awareness further, we should stop looking at responses to the mirror as its litmus test. Only with a richer theory of the self and a larger test battery will we be able to determine all of the various levels of self-awareness, including where exactly fish fit in.”

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Can fish recognize their own reflection?

When fish swim up to the glass, do they recognize...

A previously unknown <a href="http://www.earth.com/news/dinosaur-like-reptile-chewed-bones/">dinosaur</a> species from 140 million years ago has been discovered in Patagonia. The fossilized skeleton has extremely long and sharp spikes protruding from its spine.

The new species, which was named Bajadasaurus pronuspinax, had thick sheaths covering the backbone spikes that may have created the appearance of horns. This is believed to have deterred attackers, while helping the creatures look more sexually appealing to potential mates.

“These spines must have been covered by a keratin sheath similar to what happens in the horns of many mammals,” said Pablo Gallina, a researcher at the <a href="https://en.wikipedia.org/wiki/National_Scientific_and_Technical_Research_Council">National Scientific and Technical Research Council</a> (CONICET).

“We think that had they been just bare bone structures or covered only by skin, they could have been easily broken or fractured with a blow or when being attacked by other animals.”

The dinosaur existed just after the Jurassic period at the beginning of the Cretaceous period, and was most likely an herbivore.  

[caption id="attachment_1867336" align="aligncenter" width="650"]<a href="https://www.earth.com/wp-content/uploads/2019/02/spikes-spikes.jpg"><img class="size-full wp-image-1867336" src="https://www.earth.com/wp-content/uploads/2019/02/spikes-spikes.jpg" alt="" width="650" height="263" /></a> Image Credit: Jorge A. Gonzalez[/caption]

The skeleton represents the most complete specimen that has ever been found in the family of dinosaurs known as Dicraeosaurus. The family is part of the sauropods group of dinosaurs, which had long tails, long necks and small heads. The previous examples of these sauropods were not found with the extreme spikes on their backs. 

Amargasaurus cazaui, a dinosaur from the same family that lived 130 million years ago, had much shorter protrusions on its back. Scientists previously theorized that these spiked extensions supported a hump acting as a fat reservoir. Experts now believe that the spikes may have helped the dinosaurs look more attractive while providing them with a “passive defense system.”

The study is published in the journal <a href="http://www.nature.com/scientificreports">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
Main Image Credit: EPA

New dinosaur species had huge spikes to appear sexy and intimidating

A previously unknown dinosaur species from 140 million years ago...

Butterflies have sexual preference encoded in their genes, according to a pair of studies published in the journal PlOS Biology. The research helps explain why butterflies are driven to choose mates that have a similar appearance and coloring. 

The <a href="http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2005902">first study</a> was conducted by researchers from the <a href="https://www.cam.ac.uk/">University of Cambridge</a>, the <a href="https://www.en.uni-muenchen.de/">Ludwig-Maximilians-Universität</a> in Munich, and the <a href="https://stri.si.edu/">Smithsonian Tropical Research Institute</a> in Panama and examined the courtship behaviors among Heliconius butterflies. 

DNA from 300 <a href="http://www.earth.com/news/monarch-butterflies-winter-locations/">butterflies</a> was sequenced for the study and researchers wanted to know what part of the genome influenced mating preference. 

It’s the first study of its kind to look to butterfly DNA to help explain behavior and evolution. 

“There has previously been lots of research done on finding genes for things like color patterns on the butterfly wing, but it's been more difficult to locate the genes that underlie changes in behavior,” said Chris Jiggins, a lead author of the first study. “What we found was surprisingly simple - three regions of the genome explain a lot of their behaviors. There's a small region of the genome that has some very big effects.”

To understand courting and sexual preference, the researchers observed how male butterflies interacted with two different species of female butterflies. The team recorded the level of sexual interest and how long the male butterflies chased a female. 

Heliconius butterflies rely on their sight to find suitable mates, and the butterflies possess unique brightly colored wings. 

Hybridization among these species of butterflies is rare, and if a male butterfly hovered toward a hybrid female, it was because she possessed similar wing markings, the researchers found. 

After analyzing the butterfly genomes, the researchers also found that the same area of the genome that influences wing color drives sexual preferences. 

“It explains why hybrid butterflies are so rare - there is a strong genetic preference for similar partners which mostly stops inter-species breeding,” said Richard Merrill, an author of the study. “This genetic structure promotes long-term evolution of new species by reducing intermixing with others.”

For the <a href="http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2006288">second study</a>, researchers from the <a href="https://www.ed.ac.uk/home">University of Edinburgh</a> further investigated hybridization among these species of butterflies. 

Because males seek out similar looking partners, hybrids are rare. However, upon further analyses, the researchers found a rich history of genetic mixing among the few hybrids that do exist. 

A considerable amount of DNA has been shared between the different butterflies, ten times more DNA than what occurred between humans and Neanderthals. 

The butterfly’s genome not only helps sway mating behavior, as the second study also found that the genome helps maintain the unique coloring and mating preference in the different species. This ensures the long-term survival of the species.

The researchers plan to study the butterfly genomes and evolution further to see if behavior can be manipulated with genetic changes. 

“Next we would like to know how novel behavior can arise and what kind of genetic changes you need to alter behavior,” said Jiggins. “We already know that you can make different wing patterns by editing the genes. These studies suggest that potentially new behaviors could come about by putting different genes together in new combinations.”

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Image Credit: Chris Jiggins

Butterflies evolved to choose similar looking mates

Butterflies have sexual preference encoded in their genes, according to...

It started with President Donald Trump, who ordered the Bureau of Land Management (BLM) to maximize water for the farmers of the San Joaquin Valley as drought and climate change continue to plague the arid western United States.  Evidence shows that fish in the estuary of the Sacramento-San Joaquin delta are in decline. Despite this, Trump’s plan proposes to pump water from the delta southward. The plan is largely supported by agri-business that would potentially profit from more water.  Those opposed to the Trump plan include commercial fishermen that would suffer as well as environmentalists and those concerned with water quality near the delta itself. 

As for now, the Sacramento-San Joaquin Delta is part of an ecosystem supporting a diversity of species despite the human impact of water usage.  The <a href="https://www.watereducation.org/aquapedia/sacramento-san-joaquin-delta-fish-and-wildlife">Water Education Foundation</a> reports that the delta is home to more than 55 fish species as well as more than 750 wildlife and plant species.  Four separate runs of Chinook Salmon spawn in the San Joaquin River, identified by the different times of year they cross under the Golden Gate Bridge.  The Winter-run Chinook Salmon are an endangered species and the spring-run Chinook are a threatened species. In addition to the native species, there are over 200 introduced species living in the area.  Invasive species include fish that were introduced for fishing.

Competition from exotic species along with contaminants, water usage and overfishing have led to a decline of native wildlife in the delta.  Studies from 2002 and 2004 have shown a decline in pelagic species and especially a decline in juvenile striped bass and Delta smelt. The Delta smelt is a small, three inch long fish found only in the Sacramento-San Joaquin delta.  The smelt is naturally vulnerable, besides living in such a small area, it has a lifespan of only one year and has a limited diet. Overall the decline of the delta due to human causes has led to 100 wildlife species, 140 plant species and 13 fish to be protected in one way or another by state or federal regulation.            

<a href="https://www.mercurynews.com/2018/01/08/editorial-block-trump-plan-to-pump-delta-water-south-to-the-central-valley/">The Mercury News</a> reports that the California state government is trying to block the Trump administration’s plan to allocate less water to the fragile Sacramento-San Joaquin Delta. Currently, as little as 20% of the San Joaquin River reaches the ocean, making it one of the most overused rivers in California.  Preliminary proposals by California’s State Water Resources Board would raise the amount of water reaching the sea to 45-65%. More detailed water usage plans are to follow. 

Trump won support of the California farmers he would now supply with water, saying on the campaign trail, “It’s is ridiculous where they’re taking the water and shoving it out to sea.”

Now it appears President Trump is trying to fulfill promises by promoting a maximum water delivery plan.  Unfortunately for the president, the state of California has very different ideas on how to allocate water.          

<a href="https://www.sacbee.com/latest-news/article214437104.html">The Sacramento Bee</a> reported last year on a new plan for water allocation in California.  California’s State Water Resources Control Board boldly proposed allocating less water for humans and agriculture and more for fish.  The board cited the decline of several fish species and the possibility of a looming environmental catastrophe as justification for the plan.  Not only does allowing more water to flow to the sea support wildlife and communities in the delta region, it also allows more water to refill the ground water, including aquifers that are being used for agriculture.  

The plans by the board are also in conflict with plans by California’s former governor Jerry Brown, who proposed new pipes in the Sacramento-San Joaquin Delta to move water south.  Under Jerry Brown’s plan, water flow of the San Joaquin to the sea would increase to 30%-50% of its natural state. 

For an idea of the impact of less or more water flow into the Sacramento-San Joaquin Delta, it’s helpful to look at salmon numbers of salmon caught that were hatched during <a href="http://www.earth.com/news/california-drought-winners-losers/">historic drought conditions</a>.  <a href="https://fishbio.com/field-notes/the-fish-report/value-california-salmon">Fish Bio</a> reports that salmon and the profits made from fishing them declined from 2013 to 2015. The profit from commercial salmon fishing in 2013 was $244 million in economic impact and $104.5 economic impact from recreational fishing.  Those numbers dropped to $88.4 million economic impact for commercial fishing and $33 million for recreational fishing in 2015. The fish being caught in 2015 were hatched during drought conditions. The other side of the issue is farmers who feel more water would help them succeed.  

According to the <a href="https://www.ppic.org/wp-content/uploads/californias-water-water-for-farms-november-2018.pdf">Public Policy Institute of California</a>, agriculture in California produced $50 billion in sales in 2017.  California farmers also use 40% of available water, while cities use only 10% of the state’s water, and the rest is categorized as ‘environmental’.  Farmers have steadily shifted to crops that create more profits and jobs per share of water, the financial value of farming more than doubling since the 1960s when adjusted for inflation.  Still, other businesses in California have grown, overshadowing agriculture which now is only about 2% of California’s economy. The main issue is still that everyone needs water and every industry is dependent on agriculture to feed workers at very least.

Efficiency in water delivery systems has improved, with water being more often delivered with drip and micro irrigation systems than the previous flood systems.  Unfortunately the new systems also leave no water to seep back in and recharge ground water, leading to an overall drop in ground water levels. Farmers are also growing more crops like nuts, fruits and vegetables as opposed to grains, which create more income per acre allowing them to drill deeper wells, further decreasing the ground water levels.  Unfortunately these new crops are also thirstier and less drought resistant than previous crops. Nitrates from farm runoff have also started to damage the quality of groundwater. 

California’s State Water Resources Board argues that agriculture and conservation can co-exist.  With the decline of quality water throughout California and the western US as a whole, it becomes obvious that extreme efforts at efficiency and good planning on the part of all parties is necessary.  We stand at a crossroads and the quality of life for humans and non-humans alike in the western US is at stake.

--

By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="http://earth.com">Earth.com</a> Contributing Writer

Paid for by <a href="http://earth.com">Earth.com</a>

Conservation vs agriculture: The battle over water in California

It started with President Donald Trump, who ordered the Bureau...

Scientists at the <a href="https://www.pasteur.fr/en">Institut Pasteur</a> in Paris have found evidence that suggests the most recent common ancestor of all life on Earth may have actually preferred a moderately warm environment rather than the scorching hot conditions that were previously assumed. The finding, if confirmed, could provide new insight into where some of the earliest organisms existed, according to <a href="https://www.newscientist.com/">New Scientist</a>.

All organisms living on <a href="http://www.earth.com/news/life-earth-another-planet/">Earth</a> today can be traced back to the last universal common ancestor (LUCA), which lived around 3.5 to 3.8 billion years ago in the Paleoarchean Era.  Any other organisms that may have existed this far back went extinct, while LUCA split into two groups that can be found in most living species today - bacteria and archaea.

Scientists have theorized that LUCA lived somewhere extremely hot, such as a geothermal pond, where temperatures exceeded 100 or even 200 degrees Fahrenheit. With no fossils available to study LUCA, experts must compare the genomes of its descendents. 

In 2016, a German team led by Bill Martin at <a href="https://www.uni-duesseldorf.de/home/en/">Heinrich Heine University</a> searched for universal genes that may have been present in LUCA. The researchers identified 355 genes, including one that is only found in thermophiles, organisms which thrive in scorching hot temperatures between 106 and 252 degrees Fahrenheit. 

However, New Scientist reports that Ryan Catchpole and Patrick Forterre at the Institut Pasteur do not believe this particular gene was present in LUCA. Their investigation produced two possible scenarios: LUCA lacked the reverse gyrase gene and it emerged instead in an early archaean, or LUCA did have the gene but it was lost during the evolution of bacteria. 

Martin told New Scientist that it is still possible that LUCA lived in hot conditions in an alkaline vent on the seafloor, where he believes all life originated. He explained that some of the water in alkaline vents may not have been hot enough to require the reverse gyrase gene found in thermophiles.

“The fact we found reverse gyrase in there, that’s nice, but it’s just one gene out of 355,” Martin said.
--
By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Where did the earliest common ancestor of all life actually exist?

Scientists at the Institut Pasteur in Paris have found evidence...

Scientists from the <a href="https://www.cam.ac.uk/">University of Cambridge</a> have figured out how and why species “hotspots” of <a href="http://www.earth.com/news/dams-tropical-forest-biodiversity/">biodiversity</a> from California to the Galapagos have accumulated such a wide variety of species. Thanks to a “big data” study, published February 6th in <a href="http://advances.sciencemag.org/">Science Advances</a>, scientists now know evolution speed is reliant on climate.

According to the study’s findings, tropical hotspots located near the equator have generated new species at a faster rate during the last 25 million years in comparison to areas surrounding them. However, biodiversity hotspots in more temperate areas of the world are mostly populated by immigrant species that evolved elsewhere but moved to warmer climate to either escape long-term “geological processes” like glaciers, and/or needed a location with more shelter.

“We've known for decades that just a subset of places on Earth, no more than 20%, contain about half of all vertebrate species. However, we lacked the tools and data to understand why these patterns exist," said senior author Dr. Andrew Tanentzap, from the <a href="https://www.plantsci.cam.ac.uk/">University of Cambridge's Department of Plant Sciences</a>. "Large-scale initiatives to map species across the planet and in the Tree of Life, as well as advances in computing, are expanding our understanding of evolution in exciting ways. This study can now provide an answer to the old question of why diversity varies so much across the world."

Researchers used computational techniques to combine datasets that included global distribution of 11,093 bird species and 5,302 mammals, as well as the evolutionary trees that track the origin of thousands of organisms through history. Using these datasets, researchers could then follow the development of specific species-rich areas.

By doing so, researchers found that tropical biodiversity hotspots had higher rates of speciation, the development of new species, over the last 25 million years.

"Species generation is faster in the tropics, but we can now see it is extra-quick in these hotspots of biodiversity," said lead author D.r Javier Igea, also from Cambridge's Department of Plant Sciences. "More rainfall and hotter temperatures bolster the ecosystems of tropical hotspots, producing more plants, more animals that feed on those plants, and so on. The greater available energy and range of habitats within these hotspots supported the acceleration of species diversification."

For example, Madagascar has 12 species of lemurs that diversified over the last 10 million years. And the Philippines’ 17 species of earthworm mice popped up over the last 6 million years.

But biodiversity hotspots in temperate areas of the world told a different story. "Biodiversity hotspots in temperate zones have been shaped mainly by migration that occurred during the last 25 million years," Igea said. "We suspect that this influx of immigrant species resulted from climate fluctuations across millions of years, particularly cooling. Biodiversity hotspots may have acted as a refuge where more species could survive in harsh climatic conditions.”

The Iberian lynx, for example, is now a native of the Mediterranean Basin, however it was initially found in central Europe during the Pleistocene, before the last Ice Age. And the yellow-billed magpie of California most likely was cut off to its ancestral species due to glaciations over three million years ago.

"We found that hotspots across the world all have a greater complexity of habitats and more environmental energy, but the processes that drive the biodiversity are very different for tropical and temperate zones," Igea said.

Tanentzap added, "Many of these hotspot regions have species found nowhere else on Earth, yet face devastating levels of habitat loss. Protecting these areas is vital to conserving the natural world's diversity.”

--

By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Climate dictates evolutionary speed in biodiversity hotspots

Scientists from the University of Cambridge have figured out how...

Elk have developed a number of adaptations for surviving harsh environments, and are even known to persevere after major forest disturbances such as <a href="http://www.earth.com/news/amazon-forest-fires-carbon/">forest fires</a> and logging. However, a new study has revealed that elk seem to be avoiding areas hit by the bark-beetle epidemic.

Across the northern portions of the Rocky Mountains in the United States, a large beetle outbreak has killed millions of trees. Researchers discovered that during the summer, elk are not returning to areas with extensive tree mortality. 

This behavior will greatly limit the amount of  land that will be occupied by elk in the summer months. The findings will be important to many wildlife and land managers who are responsible for managing elk populations in regions that are impacted by the bark-beetle epidemic.

“Although it is common following forest disturbances for elk to seek out and capitalize on the resulting increases in highly palatable and nutritious forage, during the summer months, elk in our study area fairly consistently avoided beetle-kill. This result is somewhat counter to how we typically think elk respond to forest disturbances,” said study lead author Bryan G. Lamont of the <a href="http://www.uwyo.edu/">University of Wyoming</a>. “It appears there are some subtle, but real differences between disturbances such as forest fires and the bark-beetle epidemic.”

Lamont pointed out that elk examined in the study were much more influenced by the presence of downed trees and the loss of canopy cover compared to the small increases in understory found in areas affected by beetles. 

“Ultimately this means that if elk are avoiding beetle-kill areas, this translates to much less forest habitat that elk typically would utilize during the summer.”

The study is published in the <a href="https://wildlife.onlinelibrary.wiley.com/journal/19372817">Journal of Wildlife Management</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The bark-beetle epidemic is pushing elk out of their natural habitats

Elk have developed a number of adaptations for surviving harsh...

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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

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

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (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

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

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> 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

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

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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

Detecting mercury contamination with the tap of a finger

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

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



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



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



Video Credit: ACS Reactions



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



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

How does salt makes things taste better?

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

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



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



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



Video/ Image Credit: ESA



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



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

Santiago, Chile in South America

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

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

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



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



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



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



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



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



Video Credit: Johns Hopkins&nbsp;



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



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

Interactive map of the universe includes 200,000 galaxies

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

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



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



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



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



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



Video Credit: ESA&nbsp;&nbsp;



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



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

Lesotho: Africa's "Kingdom in the Sky"

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



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



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



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



Video Credit: ESA&nbsp;



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



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

The city of Dublin on Ireland's east coast

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



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



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



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



Video/ Image Credit: ESA



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



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

The province of Zaragoza in northeast Spain

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



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



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



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



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



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



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



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



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



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



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"

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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

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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

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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



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Satellites capture the world's biggest and fastest waves

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



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



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



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



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



Video Credit: European Space Agency&nbsp;



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

Satellites have become essential to our survival

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