For many years, scientists believed that prehistoric kangaroos in Australia had specialized diets, relying specifically on certain types of plants or vegetation for their survival. This idea suggested that they were unable to adapt to changes in their environment, such as shifts in climate or vegetation patterns. 



When the kangaroos' preferred food sources became scarce, it was assumed that their dietary inflexibility contributed to their extinction. This theory placed dietary specialization as a key reason for the disappearance of some kangaroo species during the Pleistocene epoch.



However, recent research challenges these assumptions, suggesting that these marsupials were more resilient than we initially realized.



<h2 class="wp-block-heading" id="h-diverse-diets-of-prehistoric-kangaroos"> Diverse diets of prehistoric kangaroos</h2>



The study was carried out by experts from <a href="https://www.flinders.edu.au" target="_blank" rel="noreferrer noopener">Flinders University</a> and the Museum and Art Gallery of the Northern Territory (<a href="https://www.magnt.net.au" target="_blank" rel="noreferrer noopener">MAGNT</a>). 



The researchers used cutting-edge techniques to analyze the microscopic patterns of wear on fossilized kangaroo teeth. These patterns revealed the types of food the kangaroos ate.



The results showed that <a href="https://www.earth.com/news/giant-kangaroos-of-the-past-didnt-hop-they-walked-on-all-fours/" target="_blank" rel="noreferrer noopener">prehistoric kangaroos</a> were not limited to specific types of food. Instead, they were generalists, capable of eating a wide variety of plants. This flexibility in diet helped them survive environmental changes over time.



Focusing on fossils from the Victoria Fossil Cave at the Naracoorte Caves World Heritage Area in South Australia, the experts analyzed kangaroo diets across 12 extinct species and compared them with 17 modern species.



The Naracoorte region contains the richest and most diverse fossil deposits of kangaroos from the Pleistocene epoch, making it an ideal location for this research.



<h2 class="wp-block-heading" id="h-flexible-diets-helped-kangaroos-survive">Flexible diets helped kangaroos survive</h2>



“Our study shows that most prehistoric kangaroos at Naracoorte had broad diets. This dietary flexibility likely played a key role in their resilience during <a href="https://www.earth.com/news/protemnodon-kangaroo-fossils-may-explain-their-extinction/" target="_blank" rel="noreferrer noopener">past changes</a> in climate,” explained lead researcher Dr. Sam Arman.



Contrary to previous assumptions, the study revealed that most species were mixed feeders, capable of consuming both shrubs and grasses.



“The distinctive short-faced kangaroo anatomy led to a widespread view that sthenurines were unable to adapt their diets when climate change altered vegetation patterns, leading to their extinction,” said study co-author Professor Gavin Prideaux.



However, the findings suggest that their ability to consume a wide range of foods provided a survival advantage during periods of scarcity.



<h2 class="wp-block-heading" id="h-complex-extinction-dynamics">Complex extinction dynamics </h2>



While the ability to adapt their diets likely helped prehistoric kangaroos survive for a time, it wasn’t the only factor influencing their fate. 



The extinction of these megafaunal kangaroos also involved other challenges, such as their large body size, <a href="https://www.earth.com/news/not-all-kangaroo-ancestors-hopped-as-a-means-of-locomotion/" target="_blank" rel="noreferrer noopener">how they moved</a> (locomotion), and their interactions with early humans, who may have hunted them or altered their habitats. 



To better understand these complex extinction dynamics, the researchers plan to study fossils from other Pleistocene sites. They will focus on the critical period between 60,000 and 40,000 years ago - a time when many large animal species disappeared.



This broader investigation could reveal how different factors worked together to drive kangaroo extinctions.



"Identifying what drove the late Pleistocene megafaunal extinctions on the continents remains one of the most contested topics in historical science," noted the study authors. 



"This is especially so in Australia, which lost 90% of its large species by 40,000 years ago, more than half of them kangaroos."



<h2 class="wp-block-heading" id="h-insights-into-ecosystem-vulnerabilities">Insights into ecosystem vulnerabilities</h2>



The study highlights the ecological roles of prehistoric marsupials, offering valuable insights into the evolution of Australia’s <a href="https://www.earth.com/news/ecosystem-attack-predicting-the-success-of-species-invasions/" target="_blank" rel="noreferrer noopener">ecosystems</a>. 



“Understanding the resilience of ancient species helps contextualize why Australia has been so vulnerable to introduced large mammals like pigs, camels, and deer,” noted Professor Prideaux.



Dr. Arman uses a relatable analogy to describe dietary flexibility: “Most of the time, I don’t need to engage four-wheel drive, but this capability becomes crucial when I do need it.”



<h2 class="wp-block-heading" id="h-extinction-of-australia-s-megafauna">Extinction of Australia’s megafauna </h2>



The research, funded by the <a href="https://www.arc.gov.au" target="_blank" rel="noreferrer noopener">Australian Research Council</a>, reflects a long-standing partnership between Flinders University and MAGNT.



The research also honors the traditional custodians of the Naracoorte region, the Meintangk, Marditjali, and Potaruwutj peoples, and acknowledges the contributions of volunteers and students in collecting and preparing specimens.



The study marks an essential step in understanding the resilience of prehistoric kangaroos, their adaptable diet and the complex interplay of factors that led to the extinction of Australia’s megafauna.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/science.adq4340" target="_blank" rel="noreferrer noopener">Science</a>.



-----



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.



-----

Prehistoric kangaroos changed their diets to survive climate change

For many years, scientists believed that prehistoric kangaroos in Australia had specialized diets, relying specifically on certain types of plants or vegetation for their survival. This idea suggested that they were unable to adapt to changes in their environment, such as shifts in climate or vegetation patterns. When the kangaroos' preferred food sources became scarce, it was assumed that their dietary inflexibility contributed to their extinction. This theory placed dietary specialization as a key reason for the disappearance of some kangaroo species during the Pleistocene epoch. However,...

While staying together with family and friends can be a rewarding experience for some voles, social interaction is merely tolerable to others. New research published in the journal <a href="https://elifesciences.org/articles/72684">eLife</a> has explored how individual, sex, and species differences among voles influence their social lives.&nbsp;



Since similar <a href="https://www.earth.com/news/plant-hormones-crop-invaders/">hormones</a> and brain structures are involved in social interactions in many species, including humans, this study can shed more light on some of the foundations of social differences.&nbsp;



According to scientists, some vole species, such as prairie voles, form long-lasting social bonds with their mates, as well as same-sex peers. On the other hand, meadow voles form social relationships only to help them survive the winter and part ways in warmer months.



"We wanted to determine why voles of these two species spend time in social contact," said study first author Annaliese Beery, a biologist at the <a href="https://www.berkeley.edu/">University of California, Berkeley</a>. "Specifically, we wanted to know what role social motivation plays in their behavior, or to what extent social selectivity is more about avoiding strangers."



In order to answer these questions, Beery and her team trained prairie and meadow voles to push a bar to receive food rewards. Afterward, they replaced the food with brief access to familiar voles or strangers to see how often they would push the bar to get access to the other animal.



The researchers found striking species and sex differences structuring the voles’ behavior. While female prairie voles worked harder to see familiar voles rather than strangers, male prairies voles did not show a preference for close acquaintances. Instead, they worked harder to approach females rather than males. The meadow voles, which were only females, did not seem very interested in any type of social interaction.



The results indicate that prairie voles found social interaction with familiar animals more rewarding, while the meadow voles, although likely to tolerate family or friends, did not seem to find much satisfaction in social interactions in general.



By analyzing the brain chemistry of these animals, the scientists discovered that variations in behavior were associated with concentrations of oxytocin – a hormone linked to sociality. While animals with more oxytocin receptors in a part of the brain called the nucleus ambiens were more social, those with more receptors in the bed nucleus of the stria terminalis were more aggressive.



"Knowing more about how the mechanisms supporting social relationships are similar and different across species and sexes will help us understand which mechanisms are universal and which are species-specific,” concluded Beery.&nbsp;



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Social behavior of voles linked to oxytocin levels

While staying together with family and friends can be a...

With lockdowns being lifted in many parts of the world, a large number of <a href="https://www.earth.com/news/dogs-and-cats-test-positive-for-alpha-variant-of-sars-cov-2/">dogs</a> left home alone by their owners face psychological problems such as separation anxiety. 



While it may seem that dogs who are left home with other canine companions would feel less lonely and anxious, a new study led by the Academy for Animal Naturopathy in&nbsp;Dürnten, Switzerland has found that the opposite is usually true. Dogs appear to be even more anxious when left home with other dogs.



“Many dogs are left alone at home by their owners for several hours on a daily basis. This practice is known to be a possible source of complication in dog keeping. Behaviorists and veterinarians are frequently consulted due to excessive vocalizations, destructive behavior and house-soiling of dogs left alone by their owners,” explained the study authors.&nbsp;



“These observations are thought to be symptoms of a disorder which most authors refer to as separation anxiety or separation related behavior.”&nbsp;



Signs of separation anxiety in dogs include barking, howling, increased physical activity, digging, scratching, disruptive chewing, or excessive urination and defecation.



The scientists videotaped 32 dogs in single-dog households and 45 dogs in multi-dog households that were left alone as part of their usual routine. Surprisingly, intense physical activity was higher in multi-dog households, primarily in the first hours after separation.&nbsp;



“We observed more separation-related behavior in multi-dog households,” reported study lead author Gerrit Stephan, a researcher at the Academy for Animal Naturopathy.



“It's a common misconception – and often given as poor advice – that a dog with separation-related anxiety will fare better and show fewer stress responses if another dog is added to the household,” said Natalie Waran, a professor of Animal Welfare at the <a href="https://www.eit.ac.nz/">Eastern Institute of Technology</a> in New Zealand.&nbsp;



“This doesn't address the underlying problem for the dog with separation anxiety, and it often results in another dog showing anxious or excitable behavior. The key is to understand the causes of problem behavior to be able to manage or treat those effectively.”&nbsp;&nbsp;



Further research is needed in order to better understand the reasons why separation anxiety appears to be stronger in multi-dog households and to open therapeutic pathways for pets struggling with emotional issues.



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S0168159121002501#!">Applied Animal Behavior Science</a>.



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Dogs get more separation anxiety when left with another animal

With lockdowns being lifted in many parts of the world,...

Plenty of evidence shows that invasive species damage <a href="https://www.earth.com/news/climate-change-damages-the-base-of-the-marine-food-web/">food webs</a> but the specifics of these damages over time remain somewhat mysterious. A new study conducted at the <a href="https://www.umt.edu/">University of Montana</a> Flathead Lake Biological Station is providing new insight into the impacts of invasive species.&nbsp;



"This has been a truly collaborative effort," said Shawn Delvin of FLBS. "The work leverages the rather bleak history of introduction and invasion of nonnative species in northwest Montana lakes into an ecological experiment built on the power of long-term data and a deeper understanding of lake ecology.”



U.S. Fish &amp; Wildlife biologist Charles Wainright, who just finished his graduate school work at FLBS explained the importance of the study.



“This study provides new details about how invasive lake trout affect entire lake food webs," said Wainright. "The findings will be important for conserving native species and ecosystems in Montana and elsewhere.”



The researchers examined long term fisheries records to determine the timing of introduction of invasive lake trout in ten Montana lakes. The researchers also examined the impact of these introductions on the food webs in the lakes.&nbsp;



The results showed that native fishes were forced to feed on less than ideal diets and scrape by in unfamiliar habitats. Eventually, this led to the loss of native bull trout, a threatened species under the US Endangered Species Act.&nbsp;



“Native bull trout populations have drastically declined in many lakes across western Montana due to competitive interactions with invasive lake trout," said Clint Muhlfeld, an aquatic ecologist with the USGS.



"For the first time, we show what happens not only to bull trout but entire food webs supporting them as lake trout invade and upset lake ecosystems over time.”&nbsp;&nbsp;



The research showed the invasive fish populations grew over time for decades. After 50 years, lake trout were the dominant apex predator in these food webs.&nbsp;



The findings confirmed that over time, invasive lake trout disrupted - and ultimately replaced - the native fish species, drastically changing the ecosystem.&nbsp;&nbsp;&nbsp;



The study is published in the journal <a href="https://www.pnas.org/">Proceedings of the National Academy of Sciences</a>,&nbsp;



---



By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Invasive species can drastically alter food webs

Plenty of evidence shows that invasive species damage food webs...

Researchers have long been fascinated by the extraordinary skills spiders show in building intricate and beautiful <a href="https://www.earth.com/news/coral-reef-food-webs-threatened-by-the-loss-of-picky-eaters/">webs</a> by relying mostly on the sense of touch.&nbsp;



A team of scientists led by <a href="https://www.jhu.edu/">Johns Hopkins University</a> has recently used night vision and artificial intelligence to track and record every movement the spiders made in order to shed more light on how creatures with such small brains are capable to build these elegant, complex, and geometrically precise structures.



“I first got interested in this topic while I was out birding with my son. After seeing a spectacular web, I thought, 'if you went to a zoo and saw a chimpanzee building this, you'd think that's one amazing and impressive chimpanzee,'” said senior author Andrew Gordus, a behavioral biologist at Johns Hopkins.&nbsp;



“Well, this is even more amazing because a spider's brain is so tiny and I was frustrated that we didn't know more about how this remarkable behavior occurs. Now we've defined the entire choreography for web building, which has never been done for any animal architecture at this fine of a resolution."&nbsp;&nbsp;&nbsp; &nbsp;



Gordus and his colleagues designed an arena with infrared lights and cameras to record the web-building activities of six hackled orb weavers, a species of spider native to the western United States. They used machine vision software designed specifically to detect limb movements in order to track the millions of individual leg movements the spiders performed in order to build their webs.



By analyzing the footage, the scientists found that web-making behaviors were extremely similar across spiders.&nbsp;



"Even if the final structure is a little different, the rules they use to build the web are the same," Gordus explained. "They're all using the same rules, which confirms the rules are encoded in their brains. Now we want to know how those rules are encoded at the level of neurons."



In future studies, the researchers aim to experiment with mind-altering drugs to determine which circuits of the spiders’ brains are responsible for each stage of web-building.



"The spider is fascinating because here you have an animal with a brain built on the same fundamental building blocks as our own, and this work could give us hints on how we can understand larger brain systems, including humans,” said study lead author Abel Corver, a graduate student at Johns Hopkins.



The study is published in the journal <a href="https://linkinghub.elsevier.com/retrieve/pii/S0960982221012707">Current Biology</a>.



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Scientists reveal spiders’ web-making secrets

Researchers have long been fascinated by the extraordinary skills spiders...

Instances of animals being infected with SARS-CoV-2 (the virus that causes <a href="https://www.earth.com/news/new-evidence-that-covid-19-is-a-seasonal-infection/">COVID-19</a>) have bee)n documented from around the world. The species affected include pet dogs, cats and ferrets, zoo animals such as big cats, otters and primates, farmed mink and wild white-tailed deer. 



A new study reports the first instav7thnce of pet infection by the alpha&nbsp;variant of SARS-CoV-2, which&nbsp;was first detected in southeast England and is commonly known as the UK variant or B.1.1.7. This variant rapidly outcompeted pre-existing variants in England due to its increased transmissibility and infectivity.&nbsp;



Two cats and one dog returned positive PCR tests for this variant of the Coronavirus, while two additional cats and one dog displayed antibodies to the virus two to six weeks after they had developed signs of cardiac disease. All of the pets had suffered an acute onset of cardiac disease, including severe myocarditis (inflammation of the heart muscle).



Many of the owners of these pets had also tested positive for COVID-19, and had developed respiratory symptoms several weeks before their pets became ill.



“Our study reports the first cases of cats and dogs affected by the COVID-19 alpha variant and highlights, more than ever, the risk that companion animals can become infected with SARS-CoV-2,” said lead author Luca Ferasin,&nbsp;DVM, PhD, of The Ralph Veterinary Referral Centre, in the UK.



“We also reported the atypical clinical manifestations characterized by severe heart abnormalities, which is a well-recognized complication in people affected by COVID-19 but has never been described in pets before."&nbsp;



"However, COVID-19 infection in pets remains a relatively rare condition and, based on our observations, it seems that the transmission occurs from humans to pets, rather than vice versa."



The study is published by <a href="https://onlinelibrary.wiley.com/">Wiley</a> in the journal <a href="https://bvajournals.onlinelibrary.wiley.com/journal/20427670">Veterinary Record</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Dogs and cats test positive for alpha variant of SARS-CoV-2

Instances of animals being infected with SARS-CoV-2 (the virus that...

In many animal species, <a href="https://www.earth.com/news/blue-orchard-bees-respond-to-fires-by-producing-more-females/">females</a> apparently choose male mates based on the presence of adornments, such as large antlers or bright colors, or the use of ritualized displays that in some way indicate a male’s fitness. This is known as sexual selection and is thought to be responsible for the presence of extravagant and unusual male characteristics.&nbsp;



But when the pool of possible mates is limited, females who are too choosy run the risk of ending up with no partner and no possibility of reproducing. The risks associated with female choosiness were the subject of a recent study by Wolfgang Forstmeier of the Max Planck Institute for Ornithology in Germany, and colleagues, who used populations of captive zebra finches (Taeniopygia guttata) to test their hypotheses.



Zebra finches are socially monogamous songbirds that have regionally distinct songs. Females prefer to select mates that have the same song dialect.&nbsp;



The researchers capitalized on this situation and set up 10 aviaries, each containing 12 male and 12 female finches from the two different dialect lineages. In each captive breeding colony, one-third of the females (4 birds) could choose from two-thirds (8 birds) of the males that shared the same dialect. This was considered to be a situation of relaxed competition as there was an excess of males from which the 4 females could select a suitable mate.&nbsp;



However, in each aviary the remaining two-thirds of females (8 birds) had only one-third of the males (4 birds) that shared their song dialect. This was thus a situation of high competition as these females had a shortage of preferred males from which to select a mate. They could either choose a male with a different song dialect or choose not to breed at all.



The researchers hypothesized that females that experienced high competition for mates would have less reproductive success (measured in terms of offspring that reached independence). They also theorized that these females would lay fewer eggs and start egg-laying later – because they would be busy competing for mates.



The results showed that 31 percent of females in the high-competition treatment chose to pair with a male of a different song dialect, while 26 percent refused to settle for this and remained unpaired throughout the experiment. The researchers termed these unpaired females “wallflowers.”



The surprise came, however, when it turned out that the “wallflowers” produced, on average, the same number of eggs and successful fledglings as the breeding pairs. It seems that there was no shortage of mating opportunities between unpaired females and paired males.&nbsp;



The unpaired females then chose either to build a nest and rear the young on their own, or they sneaked their fertilized eggs into the nests of pair-bonded individuals and left the chick rearing to them, like a cuckoo does.



Some previous studies have suggested that there will be a cost to a female that is too fussy when selecting a male, and that this cost (not reproducing) would act against the evolution of sexual selection as a process. However, the current study found that females who refused to pair with a male of the wrong song dialect would suffer no cost at all in terms of offspring produced.&nbsp;



In addition, unpaired females chose to mate with, and to deposit their eggs in the nests of males that had the same song dialect. With this reproductive strategy, these unpaired females were achieving the desired result even though they were not able to form pair-bonds with the preferred males.



The study is the first to quantify the fitness costs to females of being too picky. And indeed, the results indicate that, at least in zebra finches, these costs are non-existent, as long as the females are able to employ alternative reproductive strategies. This behavioral flexibility can facilitate the evolution of female choice and male sexual selection in monogamous species, the authors say.



“Our study asks how females cope with the situation that their mate preferences are difficult to satisfy," said Forstmeier. "The answer is: more successfully than we had expected.”



The study is published today in the journal <a href="https://journals.plos.org/plosbiology/">PLoS Biology</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Female finches can afford to be picky when selecting a mate

In many animal species, females apparently choose male mates based...

Many consumers are concerned about the presence of toxic <a href="https://www.earth.com/news/pesticides-have-become-increasingly-toxic-to-insects/">pesticides</a> in their food, but few are aware of the effect that these harmful chemicals are having on ecosystems. Bees and other pollinators are essential to the world’s ecosystems and their decline presents some devastating predictions.



New research from the Centre for the Study of the Sciences and the Humanities at the <a href="https://www.uib.no/en">University of Bergen</a> (UiB) is investigating the implications that insect and pollinator decline will have on society as a result of toxic pesticide usage.&nbsp;



“What is at stake is nothing less than the world’s ecosystems and food production,” said Professor Jeroen van der Sluijs of the research center. He noted that data contained in the Global Biodiversity Information Facility database illustrates that the biodiversity of wild bees has decreased by 25 percent since 1990.



Wild bees are key pollinators to many plants, facilitating the formation of seeds and reproduction, and their decline presents a serious threat to these plants and their survival.&nbsp;



“The decline in bees and other pollinators continues with increasing strength, and we are running out of time,” said Professor Van Der Sluijs.&nbsp;



Researchers have been tracing the decline of insects due to the modern use of pesticides, toxic chemicals with high levels of usage that are currently being ignored by the European regulatory system. This is due to a common misconception that modern pesticides are far safer than they used to be, but Professor Van Der Sluijs says that this is simply not true.



His research demonstrates that environmental contamination from the "neonicotinoids" found in modern-day pesticides is linked to a decline in wild bee and other pollinator populations.



“One main reason why modern pesticides are not yet banned is that researchers have not taken enough responsibility for communicating the crucial expertise needed for governments and other decision-makers to make informed choices."&nbsp;



To combat this lack of responsibility and communication, Professor Van Der Sluijs is urging fellow researchers to take on the social responsibility, investigate the pesticide crisis and communicate the results to industries. However, the researcher is aware that this will be difficult.



“Assuming one’s social responsibility as a scientist is always an uphill struggle. The academic reward system pushes you to prioritize scientific impact over societal impact,” said Professor Van Der Sluijs.&nbsp;



To communicate critically important knowledge and make a genuine impact, insect researchers must engage in transdisciplinary coalitions with governments, politicians, and industries. Through these relationships, Professor Van der Suijs believes that scientists may be able to bring their knowledge and awareness of early warning signals to the light of decision-makers.



The research is published in the journal <a href="https://www.journals.elsevier.com/current-opinion-in-insect-science">Current Opinion in Insect Science</a>.



---



By <a href="mailto:calumvaughan05@gmail.com">Calum Vaughan</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Global bee decline continues, and we are running out of time

Many consumers are concerned about the presence of toxic pesticides...

Indian jumping ants are active <a href="https://www.earth.com/video/how-tyrannosaurs-grew-into-fierce-predators/">predators</a> with large jaws. They live in small groups, each one with a queen that lays eggs, and with workers that forage and defend the colony. Unlike most species of social ants, however, there is very little difference in appearance between the workers and the queen. If a queen dies or is removed, the workers have the ability to switch castes and begin laying fertilized eggs like a queen. These queen-like workers are called gamergates.



Although differences in the levels of certain hormones have been associated with switches between worker and gamergate castes, the exact mechanism which underlies caste-specific behavior changes has not been known.&nbsp;



Now, researchers at the <a href="https://www.upenn.edu/">University of Pennsylvania</a> and the University of Freiburg, Germany, have discovered that a single protein, Kr-h1 (Krüppel homolog 1), acts in the brains of both worker ants and gamergates to produce caste-appropriate behavior. In addition, socially regulated hormones are involved in coordinating the complex social transition from worker to gamergate caste.&nbsp;



“Animal brains are plastic; that is, they can change their structure and function in response to the environment,” said Roberto Bonasio of the University of Pennsylvania Perelman School of Medicine. “This process, which also takes place in human brains – think about the changes in behavior during adolescence – is crucial to survival, but the molecular mechanisms that control it are not fully understood. We determined that, in ants, Kr-h1 curbs brains’ plasticity by preventing inappropriate gene activation.”



Ants in the colony all have the genetic information required to behave in both ways, as a worker or as a queen. Yet, under normal circumstances the ants belong to one caste only and behave in a socially appropriate way for that caste. The workers maintain the colony by finding food and fighting invaders, while the queen’s main task is to lay eggs.&nbsp;&nbsp;



By studying ants, Bonasio and colleagues wanted to understand how turning certain genes “on" or “off” affects brain function and behavior. Because&nbsp;Harpegnathos&nbsp;adults can switch from a worker to a gamergate, they were perfect study animals.&nbsp;



In order to investigate the underlying molecular events that cause the switch in behavior, the research team isolated neurons from the ants’ brains and cultured them in the laboratory. They exposed the cultured neuronal tissue to different levels of two hormones, juvenile hormone 3 (JH3) and ecdysone (E20) to see how these hormones affected gene expression in the brain cells.&nbsp;



The study revealed that the two hormones, which are normally present at different levels in the bodies of workers and gamergates, produced distinct patterns of gene activation in the brains of the two castes. In addition, the experts found that both hormones influenced the cells by activating a single protein, Kr-h1. The hormones directed the transcriptional factor (Kr-h1) to repress the expression of different target genes in the two castes of ants.



In more detailed experiments, the researchers knocked down (silenced) the Kr-h1 protein in ant brains and found that this caused the activation of gamergate genes in workers, and the activation of worker genes in gamergates. This situation led to inappropriate behavior by ants and a destabilization of caste identity.



“This protein regulates different genes in workers and gamergates and prevents the ants from performing ‘socially inappropriate’ behaviors,” said study co-author Shelley Berger. “That is to say, Kr-h1 is required to maintain the boundaries between social castes and to ensure that workers continue to work while gamergates continue to act like queens.”



“We had not anticipated that the same protein could silence different genes in the brains of different castes and, as a consequence, suppress worker behavior in gamergates and gamergate behavior in workers,” added Bonasio. “We thought that these jobs would be assigned to two or more different factors, each of them only present in one or the other brain.”



The findings establish that socially important hormones and gene regulation are at the basis of the ability of animal brains to switch from one genetic mode and social caste to another.&nbsp;



“The key message is that, at least in ants, multiple behavioral patterns are simultaneously specified in the genome and that gene regulation can have a great impact on which behavior that organism carries out,” said Berger. “In other words, the parts of both Dr. Jekyll and Mr. Hyde are already written into the genome; everyone can play either role, depending on which gene switches are turned on or off.”



The researchers think the implications may go much further than understanding behavioral plasticity in ants and other insects. “It is tempting to speculate that related proteins might have comparable functions in more complex brains, including our own,” said Bonasio. “Discovering these proteins might allow us to one day restore plasticity to brains that have lost it, for example aging brains.”



The research is published today in the journal <a href="https://www.cell.com/">Cell</a>.



---



By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

A single molecule can switch an ant from worker to queen

Indian jumping ants are active predators with large jaws. They...

Blue whales are commonly known to be the world’s largest mammal, belonging to the family of baleen whales. These whales eat an enormous amount of food and contribute to <a href="https://www.earth.com/news/upper-ocean-layer-contains-24-trillion-pieces-of-microplastics/">ocean</a> health by doing so, and a new study suggests that the massive creatures are eating even more than what has been documented.



A team of researchers at the <a href="https://www.si.edu/">Smithsonian</a> National Museum of Natural History has concluded that baleen whales eat around three times the amount of food that was previously estimated. This means that the number of nutrients they excrete, and thus contribute to ocean ecosystems, is far greater than initially expected.



The findings are providing key insights into the importance of conserving whale populations to maintain ocean health.&nbsp;



“Our results say that if we restore whale populations to pre-whaling levels seen at the beginning of the 20th century, we’ll restore a huge amount of lost function to ocean ecosystems,” explained study lead author Nicholas Pyenson.



Pyenson’s research team tracked 321 whales from seven different species across the Atlantic, Pacific, and Southern oceans, collecting data based on their food intake between 2010 and 2019.&nbsp;



Drone photography was used to measure the length of each individual to accurately estimate its body mass and thus the amount of water it filtered with each mouthful. In addition, echo-sounding technology was used to measure the density of prey species within the local waters.



Previous estimates suggested that whale populations within the California Current Ecosystem required around two million metric tons of food annually, but the new data suggests that this is actually the amount that is required for each individual species population of whales.



In addition to studying prey consumption, the researchers also calculated the amount of nutritious iron that would recirculate in the ecosystem through whale feces because of the new estimates. Using prior research, they discovered that large whales in the Southern Ocean recycle around 1,200 metric tons of iron annually, providing around 10 million times more iron found in Antarctic Seawater.



The findings led researchers to model what the marine ecosystem would look like a century ago, prior to mass whale slaughtering. The model predicted that Southern Ocean whales consumed around 430 million metric tons of krill annually in the early 20th century, a number that represents double the amount of krill found in the Southern Ocean today. Consequently, 20th-century whales would have produced 12,000 metric tons of iron annually, which is ten times the current amount.&nbsp;



Overall, the study concluded that restoring whale populations could have a highly beneficial impact on lost marine productivity, boosting the amount of carbon dioxide that is taken up by phytoplankton and thus helping to mitigate global warming.



“Our results suggest the contribution of whales to global productivity and carbon removal was probably on par with the forest ecosystems of entire continents, in terms of scale,” explained Pyenson. “That system is still there, and helping whales recover could restore lost ecosystem functioning and provide a natural climate solution.”



The research is published in the journal <a href="https://www.nature.com/">Nature</a>.



---



By <a href="mailto:calumvaughan05@gmail.com">Calum Vaughan</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Large whales make a major contribution to ocean health

Blue whales are commonly known to be the world’s largest...

New research from the <a href="https://www.bristol.ac.uk/">University of Bristol</a> shows that when dwarf mongooses observe aggressive <a href="https://www.earth.com/news/work-life-conflicts-have-a-negative-impact-on-health/">conflicts</a> between group members, they can recognize bullies. The experts found that the mongooses store this information and act on it later, often giving the bullies the "cold shoulder."



“Conflict management strategies have evolved to keep the peace in species as varied as chimpanzees, ravens and domestic dogs," said study lead author Dr. Amy Morris-Drake.



"Our work demonstrates that dwarf mongooses have sufficient cognitive ability to monitor vocal cues about aggressive interactions and to remember who the bullies are, refusing to groom with them later.”



The researchers worked with mongooses habituated to human presence, allowing them close observation of the animals.&nbsp;



“The crucial experiment entailed simulating the occurrence of food contests between two group members during the afternoon, through playback of the vocalizations given by aggressors and victims," explained study co-author Dr. Julie Kern. "The rest of the group therefore heard what sounded like repeated squabbles involving these individuals.”



“On experimental days, we recorded all the grooming that individuals engaged in with their groupmates back at the sleeping burrow that evening," said senior author <a href="https://www.bristol.ac.uk/people/person/Andy-Radford-d7b5a3e1-ceb2-4561-b384-8b14dc752b8f/">Professor Andy Radford</a>. "Being groomed helps with hygiene and reduces anxiety, and grooming underpins social relationships, so is core to social life.”



After conflicts between mongooses, subordinate animals were shown to groom each other more. The mongoose who was perceived as the aggressor was groomed less often than other mongooses, showing that there is some level of reciprocity.&nbsp;



“This shows that dwarf mongooses keep tabs on conflict occurring between their group mates," said Dr. Morris-Drake. "They can identify bullies just from the vocalizations given during disputes, store this information and implement a delayed conflict-management strategy, in this case giving the bully the cold shoulder before bedtime.”



According to the study authors, the experiments show that dwarf mongooses can extract information about group conflicts, and the identity of protagonists, from vocal cues alone. "This adds to a growing body of work demonstrating the ability of social species to garner information acoustically about aggressive interactions."



The study is published in the journal <a href="https://elifesciences.org/">eLife</a>.



---



By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Mongooses recognize bullies and give them the cold shoulder

New research from the University of Bristol shows that when...

Tiger snake populations are suffering from urbanization, according to a new study from <a href="https://www.curtin.edu.au/">Curtin University</a> in Australia. The researchers found that human development has left tiger snakes isolated in small populations that are more likely to <a href="https://www.earth.com/news/loss-of-genetic-diversity-in-polar-bears-linked-to-climate-change/">inbreed</a>.&nbsp;



"Urbanization alters landscapes, introduces wildlife to novel stressors, and fragments habitats into remnant ‘islands,'" wrote the study authors.&nbsp;"Within these islands, isolated wildlife populations can experience genetic drift and subsequently suffer from inbreeding depression and reduced adaptive potential."



The researchers examined patterns of genomic diversity and population structure among tiger snakes in and around the city of Perth.



“Tiger snake populations north of the Perth rivers at Herdsman Lake, Lake Joondalup and Yanchep National Park were found to lack genetic diversity while wetlands south of the Swan/Canning River system were home to the most genetically diverse populations of snakes, meaning they were less prone to inbreeding," explained study lead author and PhD candidate Damian Lettoof.



"If tiger snake populations isolated by urbanization are suffering from lower genetic diversity, they can lose their ability to adapt in order to survive ever-changing environments due to development, pollution and climate change."



"This is probably due to them being unable to cross unsuitable habitat such as large rivers, arid areas, and now the urban landscape."



Tiger snakes are an important part of their wetland habitats and are indicators of environment health overall.&nbsp;



"Tiger snakes are near the top of their food chain and have very specific habitat requirements, meaning a wetland with a snake population lacking in genetic diversity was indicative of an ecosystem that was not healthy or well-functioning," said Lettoof.



"This means many other small species - such as frogs, lizards and fish - living in these wetlands that are increasingly being 'cut off' by urban development may also be suffering and at risk of population decline and even extinction."



The research has important implications for conservation as well as what future expansion of urbanization may look like. "Our research suggests larger wetlands being encroached upon by urbanization such as those on the Swan coastal plain need to be managed as 'islands' of urban biodiversity in order to protect the animal communities inhabiting them."



The study is published in the journal <a href="https://journals.plos.org/plosone/">PLOS ONE</a>.



---



By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Urbanization forces tiger snakes to inbreed

Tiger snake populations are suffering from urbanization, according to a...

Ecosystems that are structured around the relationship between animals and the <a href="https://www.earth.com/news/one-third-of-plants-are-completely-reliant-on-animal-pollinators/">plants</a> they consume are becoming unbalanced as large herbivores vanish. A new study has found that there are not enough large wild herbivores left on our planet in order for these ecosystems to function smoothly.



“Large herbivores provide key ecosystem processes, but have experienced massive historical losses and are under intense pressure, leaving current ecosystems with dramatically simplified faunas relative to the long-term evolutionary norm,” wrote the study authors.



Although June 2021 witnessed the start of the <a href="https://www.decadeonrestoration.org/">United Nations Decade on Ecosystem Restoration</a>, with 115 countries committing to restore up to a billion hectares of nature worldwide, one of the biggest challenges will be to discover what levels of herbivore restoration will be necessary for a balanced functioning of ecosystems.



In order to answer this question, a research team led by <a href="https://international.au.dk/">Aarhus University</a> and the <a href="https://www.sussex.ac.uk/">University of Sussex</a> calculated a baseline for large animals based on the ratio between producers and consumers (that is, plants and herbivores) in natural reserves in Africa. A close match between large herbivores and the amount of plants they can eat currently exists only in Africa, according to the researchers.



"African ecosystems have species-rich mammal fauna and a large biomass of big herbivores that are significantly linked to plant productivity," explained study lead author Camilla Fløjgaard, an ecologist at Aarhus University. "But we can't find this pattern on other continents, and in general the large herbivore biomass is much lower than we would expect considering the level of productivity.”



By analyzing data from natural areas, as well as several protected regions, reserves, and rewilding projects in Europe, the scientists discovered that the biomass for large herbivores in natural areas was less than one-tenth of the biomass found in fenced rewilding areas with restored herbivore fauna.



"It’s thought-provoking that, even in many protected areas, the number of large herbivores is only a fraction of what the areas can actually sustain," said Fløjgaard.



In order to restore the stability and biodiversity of numerous ecosystems worldwide, efforts to increase populations of wild herbivores are urgently needed.



"Bringing back big animals is crucial to restoring self-sustaining ecosystems and conserving biodiversity, but it is not going to be easy," said study co-author Rasmus Ejrnæs, a senior researcher from Aarhus University. "Large animals are troublesome, because they damage crops, disrupt traffic and generally just get in the way. It will require political commitment and careful physical planning, including fenced reserves."



The study is published in the <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2664.14047">Journal of Applied Ecology</a>.



---



By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Large herbivores must be restored to balance ecosystems

Ecosystems that are structured around the relationship between animals and...

<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...