The narrative of life on Earth has been built upon billions of years of existence, with therapsids playing a crucial role in this evolutionary story.



These ancient creatures are the direct predecessors of one remarkable group: the mammals.



Mammals, relatively recent additions to the evolutionary timeline, trace their inception to nearly 200 million years ago, amidst the prolific era of dinosaurs.



However, even mammals have antecedents, all categorized under the collective term "therapsids."



<h2 class="wp-block-heading" id="h-understanding-therapsids-the-basics">Understanding therapsids -- the basics</h2>



Therapsids thrived during the Permian period, which was over 250 million years ago. They came in all shapes and sizes, from small, nimble hunters to larger, plant-eating giants. 



What made therapsids special was their mix of reptile-like and <a href="https://www.earth.com/news/what-will-happen-if-modern-large-mammals-become-extinct/" target="_blank" rel="noreferrer noopener">mammal-like features</a>, such as differentiated teeth and more advanced jaw structures, which set the stage for the evolution of true mammals later on.



For instance, therapsids had openings on the sides of their skulls to anchor jaw muscles, as well as structures in their jawbones that eventually evolved into the distinct middle ear bones found in mammals.



As time went on, therapsids started to dominate the land, filling niches that today’s mammals occupy. 



Some therapsids even showed early signs of having warm-blooded metabolisms and better ways to regulate their body temperatures, which are key traits of mammals. 



Unfortunately, most therapsids didn’t make it past the <a href="https://www.earth.com/news/saber-toothed-predator-was-king-prior-to-the-great-dying/" target="_blank" rel="noreferrer noopener">Permian-Triassic extinction event</a>, the biggest mass extinction in Earth’s history. 



However, a few lineages survived and eventually evolved into the diverse mammals we see today. 



<h2 class="wp-block-heading" id="h-gorgonopsians-and-saber-teeth">Gorgonopsians and saber teeth</h2>



In a recently published paper, scientists are buzzing about the find of a lifetime -- an ancient therapsid <a href="https://www.earth.com/news/gordonia-traquairi-pig-like-creature-discovered-roamed-earth-250-million-years-ago/" target="_blank" rel="noreferrer noopener">fossil</a>, potentially the most ancient of its kind, that hails from an era perhaps far older than any therapsid discovery thus far.



This fossil belongs to a group known as the "gorgonopsians," and its features suggest something akin to a <a href="https://www.earth.com/news/mummified-baby-saber-toothed-cat-found-with-fur-and-toes-intact/" target="_blank" rel="noreferrer noopener">saber-toothed</a> predator with a slightly canine touch.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/gorgonopsian_oldest-mammal-ancestor_saber-tooth-fossil_credit-Anna-Sole_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/12/gorgonopsian_oldest-mammal-ancestor_saber-tooth-fossil_credit-_1s.webp" alt="Saber tooth of the therapsids gorgonopsian (cast). Credit: Anna Solé / Institut Català de Paleontologia Miquel Crusafont" class="wp-image-1954542"/></a><figcaption class="wp-element-caption">Saber tooth of the therapsids gorgonopsian (cast). Credit: Anna Solé / Institut Català de Paleontologia Miquel Crusafont</figcaption></figure>



The newly found fossil, yet to receive a species name, introduces an exciting anomaly into the therapsid fold.



Gorgonopsians, according to Ken Angielczyk, MacArthur Curator of Paleomammalogy at the Field Museum's <a href="https://nirc.fieldmuseum.org/" target="_blank" rel="noreferrer noopener">Negaunee Integrative Research Center</a>, are closer relatives to mammals than any other living species we are aware of.



"They don't have any modern descendants and, while they're not our direct ancestors, they're related to species that were our direct ancestors."



<h2 class="wp-block-heading" id="h-breaking-age-records">Breaking age records</h2>



Prior to this discovery, the record for the oldest known gorgonopsian was set at approximately 265 million years. 



The new fossil, however, has potentially pushed this benchmark back even further, dating back to somewhere between 270 and 280 million years ago.



"It is most likely the oldest <a href="https://www.earth.com/news/saber-toothed-predator-was-king-prior-to-the-great-dying/" target="_blank" rel="noreferrer noopener">gorgonopsian</a> on the planet," proclaims Josep Fortuny, a senior author of the study and head of the Computational Biomechanics and Evolution of Life History group at Spain's Institut Català de Paleontologia Miquel Crusafont (<a href="https://www.icp.cat/index.php/en/" target="_blank" rel="noreferrer noopener">ICP</a>).



<h2 class="wp-block-heading" id="h-surprising-amount-of-bones">Surprising amount of bones</h2>



The surprising find was unearthed on the Mediterranean island of Mallorca, which is part of modern-day Spain.



During the age of the gorgonopsians, however, Mallorca was a strip of land nestled within the supercontinent of Pangea. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/gorgonopsian_oldest-mammal-ancestor_fossil-fragment-outline_credit-Nat-Commun_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/12/gorgonopsian_oldest-mammal-ancestor_fossil-fragment-outline_credit-Nat-Commun_1s.webp" alt="The silhouette of the described animal showing the different anatomical elements recovered during the excavation. Credit: Eudald Mujal / SMNS" class="wp-image-1954540"/></a><figcaption class="wp-element-caption">The silhouette of the described animal showing the different anatomical elements recovered during the excavation. Credit: Eudald Mujal / SMNS</figcaption></figure>



“The large number of bone remains is surprising. We have found everything from fragments of skull, vertebrae, and ribs to a very well-preserved femur," explains Rafel Matamales, curator of the Museu Balear de Ciències Naturals (MUCBO | MBCN), research associate at the ICP, and first author of the study.



"In fact, when we started this excavation, we never thought we would find so many remains of an animal of this type in Mallorca.” 



<h2 class="wp-block-heading" id="h-a-glimpse-into-the-past">A glimpse into the past</h2>



These skeletal remnants have allowed scientists to piece together what this ancient beast might have looked like. 



"If you saw this animal walking down the street, it would look a little bit like a medium-sized dog, maybe about the size of a husky, but it wouldn't be quite right," detailed Angielczyk.



"It didn't have any fur, and it wouldn't have had dog-like ears," "But it’s the <a href="https://www.earth.com/news/one-of-earths-earliest-animals-found-in-australia/" target="_blank" rel="noreferrer noopener">oldest animal</a> scientists have ever found with long, blade-like canine teeth."



The elongated, blade-like canine teeth were a distinct feature, suggesting it was likely a top predator in its ecosystem.



<h2 class="wp-block-heading" id="h-therapsids-and-mammal-evolution">Therapsids and mammal evolution</h2>



The existence of this ancient gorgonopsian that predates its closest relatives by tens of millions of years, redefines when scientists believe therapsids first evolved.



This significant milestone also alters our understanding of the eventual emergence of mammals, shedding light on our own evolutionary history. 



"Before the time of dinosaurs, there was an age of ancient mammal relatives. Most of those ancient mammal relatives looked really different from what we think of mammals looking like today," acknowledges Angielczyk. 



"But they were really diverse and played lots of different ecological roles. The discovery of this new fossil is another piece of the puzzle for how mammals evolved."



---



The full study was published in the journal <a href="https://www.nature.com/articles/s41467-024-54425-5" target="_blank" rel="noreferrer noopener">Nature Communications</a>.



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World's oldest mammal ancestor ever discovered had 'saber teeth'

The narrative of life on Earth has been built upon billions of years of existence, with therapsids playing a crucial role in this evolutionary story. These ancient creatures are the direct predecessors of one remarkable group: the mammals. Mammals, relatively recent additions to the evolutionary timeline, trace their inception to nearly 200 million years ago, amidst the prolific era of dinosaurs. However, even mammals have antecedents, all categorized under the collective term "therapsids." Understanding therapsids -- the basics Therapsids thrived during the Permian period, which was over...

A new study led by <a href="https://protectedseas.net/">ProtectedSeas</a> – an organization aiming to provide open data and monitoring solutions to enhance awareness of and compliance with <a href="https://www.earth.com/news/key-ocean-species-on-the-west-coast-face-an-uncertain-future/">ocean</a> protection efforts – has found that boaters often cluster along the edges of marine protected areas (MPAs) off the coast of California. These findings suggest that fishers are aware of the MPA boundaries and cluster just outside them to benefit from better fishing opportunities.



The researchers used the ProtectedSeas&nbsp;<a href="https://protectedseas.net/marine-monitor-m2">Marine Monitor</a>&nbsp;(M2) autonomous data collection tool to continuously monitor vessel activity&nbsp;for an entire year in the vicinity of five state-managed MPAs near San Diego, Santa Barbara, and Cambria. The results revealed that 40 percent more boating and fishing activity occurred in the vicinity of the MPAs compared to the surrounding regions.



“Most activity occurred at or beyond MPA edges, and not within the area itself,” said study lead author Samantha Cope, a researcher at ProtectedSeas. “This suggests that boaters are aware of the MPA and that the areas are serving their purpose of creating safe refuges for ocean life regeneration. Fishers see a benefit from spending time near the area because MPAs are working.”



MPAs off the Californian coastline restrict fishing activities to safeguard endangered marine species and their habitats. The fact that fishing activities were more concentrated along the edges of the MPAs suggest that fish may be more abundant there. Monitoring human activity in these regions can help managers evaluate the ecological and community benefits of MPAs, detect patterns in boat activity and other human uses, and ensure that the MPA regulations are strictly followed.&nbsp;



“Conservation work needs to be driven by data, and M2 helps us understand trends in what’s happening in MPAs,” said study co-author Jessica Morten, a resource protection specialist at the <a href="https://channelislands.noaa.gov/">Channel Islands National Marine Sanctuary</a>.



The M2 monitoring system provides scientists with an independent, easy-to-use method for continuously documenting human activity in and around MPAs.&nbsp;



“We specifically designed M2 to monitor important marine places at a cost that was realistic for local managers,” said M2 Product Manager and study co-author Brendan Tougher. “This research shows that M2 is an accessible and robust tool for monitoring MPAs. As a ‘low-tech’ solution for more efficient MPA monitoring, M2 is especially valuable for anyone with limited technical experience or resources since people can be quickly trained on how to use and interpret data from our systems."



The study is published in the journal <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0269490">PLoS ONE</a>.



---



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

Fishing activities spiking near marine protected areas

A new study led by ProtectedSeas – an organization aiming...

A team of researchers led by the <a href="https://www.utexas.edu/">University of Texas at Austin</a> has recently found in New Mexico a three-foot-tall pile of <a href="https://www.earth.com/news/ancient-mammoths-survived-longer-than-initially-thought/">mammoth</a> bones dating back to 36,250 - 38,900&nbsp;years ago, together with evidence that the animals were butchered by early humans. This discovery suggests that humans settled in North America 17,000 years earlier than previously thought.



Scientists have long debated when humans first arrived to North America. While the Clovis culture, which dates back to 16,000 years ago, left behind elaborate stone tools, at older sites where such tools are absent it is more difficult to find conclusive evidence about the possibility of human activities.



Although the site where the mammoth bones were discovered lacks clearly associated stone tools, the researchers discovered an array of supporting evidence. For instance, CT scans revealed bone flakes with microscopic fracture networks similar to those in freshly knapped cow bones, as well as a series of well-placed puncture wounds that would have helped in draining grease from the ribs and vertebral bones. “There really are only a couple efficient ways to skin a cat, so to speak. The butchering patterns are quite characteristic,” reported study lead author Timothy Rowe, a paleontologist at the University of Texas at Austin.



Moreover, chemical analyses of the sediment surrounding the fossils showed evidence of fire particles that came from sustained and controlled fires, rather than lightning strikes or wildfires. The sediment also contained pulverized bone and burned remains of small animals, such as fish, birds, rodents, and lizards.



These findings lend support to previous theories based on genetic evidence from Indigenous populations in South and Central America, which argued that North America had at least two founding human populations – the Clovis and a pre-Clovis society with a different genetic lineage.&nbsp;



According to Professor Rowe, these ancient humans most likely came to the Americas from Asia. However, whether they took a coastal or overland route remains an open question. Further research is needed to clarify the migration and settlement patterns of these early human populations, as well as their behavioral, cognitive, and cultural characteristics.&nbsp;



The study is published in the journal <a href="https://www.frontiersin.org/articles/10.3389/fevo.2022.903795/full#S12">Frontiers in Ecology and Evolution</a>.



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

Humans settled in North America much earlier than previously thought

A team of researchers led by the University of Texas...

Parental care is an important strategy for protecting offspring and enhancing their chances of survival. It has evolved independently many times in different groups of animals such as <a href="https://www.earth.com/news/many-small-mammals-in-the-uk-tested-plastic-positive/">mammals</a>, birds, reptiles and arthropods. Parental care is particularly evident in many modern social insects, including bees, wasps and ants. But finding evidence of parental care among fossil organisms is extremely challenging because of the temporary nature of brooding activity.&nbsp;



In a new study led by Professor HUANG Diying&nbsp;from the&nbsp;Nanjing Institute of Geology and Palaeontology of the&nbsp;<a href="https://english.cas.cn/">Chinese Academy of Sciences</a> (NIGPAS), researchers have found the oldest evidence of brood care in an insect, the extinct water boatman, Karataviella popovi. By examining 157 fossilized individuals of this aquatic bug that lived around 160 million years ago, the researchers identified 30 females, each carrying a cluster of eggs anchored to a left leg like a bunch of tiny grapes.&nbsp;



In their paper, published in the <a href="https://royalsocietypublishing.org/journal/rspb">Proceedings of the Royal Society B, Biological Sciences</a>, the authors state that these fossils are “exceptional” and show a unique brooding strategy that is unknown in any other extinct or extant insect species. The tiny eggs, each measuring between 1.14 and 1.20 millimeters, are arranged in densely packed rows and each egg is anchored by a tiny stalk to the mesotibia of the middle leg on the female’s left side. The five or six rows of eggs are staggered, with six to seven eggs per row. This represents quite a hefty load, considering that K. popovi adults only measure around 12 mm in length.



Researchers excavated the insect fossils from the Haifanggou Formation, a fossil-filled rock deposit near the village of Daohugou in northeastern China. A wide variety of fossils have already been recovered from the site, including the preserved remains of feathered dinosaurs, ancient mammals, giant fleas and long-proboscid scorpionflies.



Today, modern species of the water boatman are common aquatic insects that can be found in many freshwater ecosystems worldwide. Interestingly, females habitually lay their eggs on various subaquatic surfaces, such as leaves, stones, and the stems of vegetation. Eggs may also be deposited on the shells of snails, the carapaces of terrapins and the exoskeletons of crayfish. The researchers hypothesize that K. popovi females probably became adapted to carry eggs around on their own legs in Jurassic times in response to various pressures present in the environment of the time.&nbsp;



Eggs need to be oxygenated as the embryos develop, and it is possible that the large eggs of K. popovi needed extra aeration due to their relatively small surface area to volume ratio. In freshwater habitats that may have become stagnant at times, carrying the eggs around would have ensured maximal flow of oxygen over them as the female swam through the water.&nbsp;



In addition, such nutrient-rich eggs would have been attractive to all sorts of predators in the underwater environment, especially if they had simply been deposited on available surfaces. Depositing the eggs onto the females’ own legs would have provided them with protection and enhanced their survival rate.



“Due to the potential high predation risk caused by abundant salamanders in the Daohugou Biota, and seasonal food resources,&nbsp;K.&nbsp;popovi&nbsp;may have been exposed to fierce ecological pressure in the Daohugou Biota,” said Professor HUANG.&nbsp;



The researchers hypothesized that K. popovi&nbsp;females likely laid the eggs directly onto their legs by first secreting a sticky mucus and then executing “specific bending movements of the abdomen” to cement the eggs onto the appropriate limb. “The unoccupied right mesotibia might have been used to maintain balance when swimming and feeding,” they wrote in their report. This unusual brooding strategy likely provided effective protection for eggs by largely avoiding the risks of predation, desiccation and hypoxia.



The researchers explained that carrying a cluster of eggs on a leg is probably a unique strategy among insects. However, it is not unusual in aquatic arthropods, where such carrying behavior can be traced back to the early Cambrian Chengjiang Biota.&nbsp;



The water boatman fossils in the current study were dated at 163.5 million years old, which places them in the middle of the Jurassic Period (201.3 million to 145.5 million years ago). The evidence of brood care in K. popovi&nbsp;is thus the earliest for any insect, pre-dating other fossil evidence of brooding behavior by around 40 million years. Among Mesozoic insects, the only other direct fossil cases of brooding behavior are from the Early Cretaceous Jehol Biota and mid-Cretaceous Burmese amber.



This discovery highlights the existence of diverse brooding strategies in Mesozoic insects, thus helping scientists understand the evolution and adaptive significance of parental care in insects.&nbsp;



Image Credit: NIGPAS



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

Jurassic water bugs stuck their eggs on their legs

Parental care is an important strategy for protecting offspring and...

The digestive system contains a beautifully dynamic <a href="https://www.earth.com/news/humans-pass-on-gut-microbes-to-urban-wildlife/">microbiome</a>. And when one element changes, other parts usually change as well. Dogs' guts follow this same pattern. With dietary changes, gut microbes shift as the different species find their role in a new environment. The change in microbial diversity affects what types of byproducts, known as metabolites, are produced in the gut.



Scientists already know this, which is why we are usually told to change our dogs' food gradually. Still, they were unsure how fast microbiomes adjust to a new diet.&nbsp;



"As long as I've been doing animal nutrition research, we've argued over how long we need to feed a new diet before collecting samples when everything's stabilized," said study co-author Kelly Swanson. "No one has ever tested it definitively."



The results of the study revealed that gut microbes in dogs are quick to find equilibrium. "Metabolites change really quickly, within a couple days. Bacteria responsively metabolize and deal with the substrates they're given in the new diet. Then it takes a few more days to sort out the microbial pecking order, if you will," explained Swanson.&nbsp;



"Our data show everything stabilizes by day six, so animal nutrition researchers could confidently sample and find a stable microbiome within 10 days."



To carry out their study, the researchers fed dogs dry kibble for two weeks and suddenly switched their diets. Half of the dogs ate high-fat, high-protein canned food, and the other ate high-fiber kibble. They repeated the study by swapping dogs with the opposite experimental diet the second time.



The experts took fecal samples two days after the switch, and every four days after that. They analyzed the poop and then linked metabolites with bacterial species, which is not an easy task.



"Oftentimes, we feed a diet and collect the feces, but there's kind of a black box in terms of what's going on in the gut. We know what some bacterial species metabolize, but definitely a lot of it is unknown," said Swanson."Our correlations are the starting point to connect some of the dots, but more targeted research still has to be done."



According to the researchers, the most surprising knowledge gathered from the study is just how quickly dogs' bodies can react to a change in diet. The experts believe other mammals could attain bacterial equilibrium within a similar timeframe.&nbsp;&nbsp;



The study is published in <a href="https://animalmicrobiome.biomedcentral.com/articles/10.1186/s42523-022-00194-9">Animal Microbiome</a>.



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By <a href="mailto:nire518@gmail.com">Erin Moody </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Dogs can adjust to new diets very quickly

The digestive system contains a beautifully dynamic microbiome. And when...

The North American West Coast is home to an underwater ocean highway - the California Current marine ecosystem (CCME), which extends from the southernmost tip of California up through Washington. Seasonal upward currents of cold, nutrient-rich water support a larger food web of krill, squid, fish, <a href="https://www.earth.com/news/seabirds-struggle-to-find-food-in-cloudy-ocean-water/">seabirds</a> and marine mammals.&nbsp;



Climate change and subsequent changes in ocean pH, temperature and oxygen levels are altering the CCME - and not for the better. In a new study from <a href="https://www.mcgill.ca/">McGill University</a>, experts warn that over the next 80 years, climate impacts will significantly affect twelve economically and culturally important species that make their home in the CCME.



The region can expect to see substantial losses of kelp, red urchins, Dungeness crab and razor clams. In addition, habitat for anchovy and pink shrimp is expected to decline.&nbsp;



The results demonstrate how complex climate research can be. For example, while some environmental changes will result in benefits such as a higher metabolism and increased growth, other changes are severe, and could decrease survival rates.&nbsp;



Physiological increases in size or consumption are not always beneficial. This is especially the case when resources such as food and oxygenated water are limited.



Of all the climate effects modeled, ocean acidification was associated with the largest decreases in biological rates in some species, and the largest increases in others. This emphasizes how climate modeling is critical to safeguarding coastal ecosystems and the future of fisheries.



These impacts will likely have socio-economic consequences across the West Coast, but they will likely not affect everyone and every place equally.&nbsp; Since the area is highly productive, supporting fisheries and livelihoods for tens of millions of residents will require the ability to predict expected change across a range of species. This could shed light on potential economic impacts and optimal adaptive measures for the future.



“The time to accelerate science-based actions is now,” said study first author Professor Jennifer Sunday..“Integrating scientific information, predictive models and monitoring tools into local and regional decision-making can promote stewardship of marine resources and contribute to human wellbeing as we face inevitable changes in the marine life that sustains us.”



The study is published in the journal <a href="https://onlinelibrary.wiley.com/journal/13652486">Global Change Biology</a>.



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By <a href="mailto:katherinebucko@gmail.com">Katherine Bucko</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Key ocean species on the West Coast face an uncertain future

The North American West Coast is home to an underwater...

Oakleaf butterflies are marvelous mimics. Although the upper surfaces of their <a href="https://www.earth.com/news/insect-wings-inspire-new-method-to-kill-bacteria-on-food/">wings</a> are colored with bright oranges and blues, the lower surfaces are dull brown and resemble dead leaves. When an oakleaf butterfly alights on a plant and folds its wings closed, it masquerades perfectly as a dead leaf, right down to the fine details of leaf stalk, midrib, veins and patches of decay. Until now, the genetics controlling this remarkable phenomenon have not been revealed.



In recent research, published in the journal <a href="https://www.cell.com/">Cell</a>, scientists have investigated the underlying genetic basis of leaf resemblance in Kallima butterflies, that are found in locations in <a href="https://en.wikipedia.org/wiki/East_Asia">east</a>,&nbsp;<a href="https://en.wikipedia.org/wiki/South_Asia">south</a>&nbsp;and&nbsp;<a href="https://en.wikipedia.org/wiki/Southeast_Asia">southeast Asia</a>. The study was focused on species found in montane and lowland biodiversity hotspots, including several islands to the south and east of the Asian mainland. By using butterflies from these diverse locations, the researchers hoped to access as many different patterns of leaf resemblance as possible, and to understand the evolution of this phenotypic diversity.



“Butterfly wings have relatively simple structures, but this simple structure is responsible for some very complex functions: locomotion, thermoregulation, mate preference, and predator avoidance,” said Wei Zhang, a butterfly researcher at Peking University in China. “Because these wings are structurally simple but functionally complex, I think butterfly wings are the ideal system to address multiple evolutionary questions.”



First, the researchers sequenced the genomes of 105 butterflies from 21 different genera in the family Nymphalidae. The results showed that leaf mimic butterflies from the Kallima genus formed a monophyletic group that was genetically distinct from butterflies of other genera in the family.&nbsp;



Next, the team analyzed the genomes of 36 butterflies from the genus Kallima, collected from 11 geographic locations in east and southeast Asia. This enabled the researchers to get an idea of the evolutionary history of this fascinating group of leaf mimics. The results suggest that this group of butterflies diversified in the eastern Himalayas during the Pleistocene Period, and subsequently dispersed to other regions in Asia, as well as to areas that are now islands. &nbsp;



The experts also sequenced the genomes of 78 individuals, all of the species K. inachus, that showed a range of different leaf patterns on their wings. By doing this, they hoped to reveal the genetic basis for the variety of different dead-leaf wing patterns found amongst this species. They were fascinated to find ten distinct leaf wing forms in total, which were most likely determined by combinations of five alleles (alternative gene forms) of the gene known as cortex. This gene is known to control wing and body color in various other moths and butterflies.&nbsp;&nbsp;



The five alleles were associated with underwing patterns that the researchers termed plain, veined, scrambled, rippled and moldy. They hypothesized that the ten distinct wing leaf patterns were likely the result of different combinations of these alleles. When this pattern of phenotypic variation exists within natural populations, it is often an indication that several different selection pressures act on the trait (lower wing pattern) and cause certain outcomes to be selected for because they increase the survival chances of individuals that carry them.&nbsp;



The researchers noted that Kallima butterflies have derived protection from resembling leaves for millions of years and that the variety of wing patterns found today are the result of evolutionary pressures on the cortex gene. The effects of the various selection pressures have resulted in balanced polymorphism, a state where the ten wing leaf patterns are all maintained in the butterfly populations today.&nbsp;



“This leaf wing polymorphism has been maintained in multiple&nbsp;Kallima&nbsp;species, but different species may have different phenotype frequencies,” explained Zhang. “I think this is due to the proliferation of specific plants in particular habitats, so the butterflies will gain more protective benefits by having different frequencies of wing phenotypes.”



The experimental method used by the team enabled them to investigate both the macroevolution and microevolution of leaf mimicry in oakleaf butterflies. “We generally focus on biodiversity at a macroevolutionary level,” said Zhang. “But we seldom have cases that illustrate in detail how species diversity and genetic diversity originated in such a diversity hotspot.”



In the future, Zhang and her team intend to examine how wing coloration and patterns vary in different regions and with different plant life. “We would like to understand how these genes facilitate, and originated, such beautiful diversifying wing patterns,” said Zhang



Further details about the study are available at:&nbsp;<a href="https://www.cell.com/cell/fulltext/S0092-8674(22)00794-2">https://www.cell.com/cell/fulltext/S0092-8674(22)00794-2</a>



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

How do oakleaf butterflies mimic dead leaves?

Oakleaf butterflies are marvelous mimics. Although the upper surfaces of...

The 2013-2015 marine heatwave, known as The North Pacific Blob, was the most significant marine <a href="https://www.earth.com/news/marine-heatwaves-could-severely-affect-the-fishing-industry/">heatwave</a> on record. Now, data collected with the help of elephant seals is giving scientists a deeper understanding of the event.&nbsp;



Much of the information from The Blob event was collected from relatively small, shallow areas. However, elephant seals allowed for a more thorough investigation.



"Female elephant seals go out into the open ocean where a ship might go through and collect data only once in awhile, whereas we have elephant seals out there collecting data all over the place," explained first author Rachel Holser. "It's unusual to have this kind of data at the resolution we have in both time and space, and at depths below several hundred meters."



Researchers have been collecting data from elephant seal migrations in the North Pacific Ocean for decades. They use advanced sensors to collect depth, temperature, and salinity data.&nbsp;



"The elephant seals collect data in different locations than existing oceanographic platforms," said study senior author Christopher Edwards, a professor of ocean sciences at <a href="https://www.ucsc.edu/">UC Santa Cruz</a>. "This is an underutilized dataset that can inform us about important oceanographic processes, as well as helping biologists understand the ecology of northern elephant seals."



The sensors revealed that The Blob created abnormally warm temperatures as far as 1,000 meters (3,280 feet) beneath the surface. The temperatures didn't return to normal until 2017, two years after the incident occurred. Experts are still unsure precisely what caused the subsurface temperature to rise dramatically.&nbsp;



"Those temperature anomalies are so deep it's unlikely it would be due to mixing from the surface," Edwards said. "One reasonable mechanism is that the unusually warm waters were transported northward from further south. What we don't know yet is whether that northward transport is directly or indirectly related to the surface warming. Changes at the surface could have altered deeper currents transiently to draw southern waters to the north."



Sub-surface warming has enormous impacts on ocean ecology and human economics. The authors hope the information in this study will help us better protect the oceans and prepare for the future.&nbsp;



"The more information we can collect, the better off we'll be in terms of understanding what's happening and facing the challenges. This study shows the value of collaborating with elephant seals to collect oceanographic data that is complementary to other methods," said Holser.&nbsp;



The study is published in <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2021JC018356">the Journal of Geophysical Research: Oceans</a>.



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By <a href="mailto:nire518@gmail.com">Erin Moody </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Elephant seals could help us understand ocean warming

The 2013-2015 marine heatwave, known as The North Pacific Blob,...

A newly discovered panda species is likely to be the last of its kind that lived in Europe, according to a new study published by the <a href="https://www.tandfonline.com/">Taylor &amp; Francis Group</a>. The discovery was made by experts during the analysis of two teeth <a href="https://www.earth.com/news/plesiosaur-fossils-found-in-a-100-million-year-old-river/">fossils</a> that were found in eastern Europe in the late 1970s and stored at the Bulgarian National Museum of Natural History.&nbsp;



The experts say that the species, which lived in the forested wetlands of Bulgaria around six million years ago, represents the “most evolved” European giant panda.



“Although not a direct ancestor of the modern genus of the giant panda, it is its close relative,” explained Professor Nikolai Spassov. “This discovery shows how little we still know about ancient nature and demonstrates also that historic discoveries in paleontology can lead to unexpected results, even today.”



The fossils include an upper carnassial tooth and an upper canine. The species has been named Agriarctos nikolovi after paleontologist Ivan Nikolov, who first catalogued the fossils at the museum over 40 years ago.&nbsp;



“They had only one label written vaguely by hand,” said Professor Spassov. “It took me many years to figure out what the locality was and what its age was. Then it also took me a long time to realize that this was an unknown fossil giant panda.”



The fossilized teeth were found in coal deposits which suggest that the panda lived in forested, swampy regions. The species had a mainly vegetarian diet, but was not completely dependent on bamboo. The researchers believe that the pandas were driven toward a plant diet due to pressure from large predators that shared their environment.



“The likely competition with other species, especially carnivores and presumably other bears, explains the closer food specialization of giant pandas to vegetable food in humid forest conditions,” said Professor Spassov.



The experts propose that A. nikolovi became extinct as a result of climate change, and was possibly a casualty of the Messinian salinity crisis -&nbsp; an event during which the Mediterranean basin dried up.



“Giant pandas are a very specialized group of bears,” explained Professor Spassov. “Even if A. niklovi was not as specialized in habitats and food as the modern giant panda, fossil pandas were specialized enough and their evolution was related to humid, wooded habitats. It is likely that climate change at the end of the Miocene in southern Europe, leading to aridification, had an adverse effect on the existence of the last European panda.”



The <a href="https://www.tandfonline.com/doi/full/10.1080/02724634.2021.2054718">study</a> is published in the <a href="https://www.tandfonline.com/toc/ujvp20/current">Journal of Vertebrate Paleontology</a>.



Image credit: Velizar Simeonovski, Chicago



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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

Relative of giant pandas lived six million years ago in Europe

A newly discovered panda species is likely to be the...

In a new study from <a href="http://www.tohoku.ac.jp/en/">Tohoku University</a>, scientists have gained a better understanding of physiological responses in <a href="https://www.earth.com/news/feeding-cattle-seaweed-could-reduce-methane-emissions/">cattle</a> with high methane emissions. In particular, the researchers investigated the metabolic characteristics of Japanese Black cattle.



In 2022, Japan's agricultural sector produced 32.3 million tons of greenhouse gas emissions, and nearly 25 percent of these emissions are linked to enteric fermentation within livestock.&nbsp;



Grazing animals such as cattle, sheep and goats are known as ruminants. These animals release enteric methane as the plant materials they feed on decompose and ferment inside of their bodies.&nbsp;



To reduce the emissions associated with grazing livestock, experts have been trying out new additives and feeding management systems.&nbsp;



"Enteric methane emitted by domestic animals is of primary concern in the livestock industry," wrote the authors of the current study. "Ruminants generally have higher methane emissions than monogastric animals because of a long digestive tract and an extensive ecosystem in the rumen that is inhabited by numerous microorganisms, including methanogens."



A team led by Professor Sanggun Roh from Tohoku University's Graduate School of Agricultural Science used physiological parameters such as blood metabolites, hormones, amino acids, rumen fermentation, and liver transcriptomes to analyze the metabolic and nutritional features that may influence methane emissions.&nbsp;



"We found cattle exhibiting high enteric methane to have a higher butyrate and lower propionate ratio," said Professor Roh.



The experts also discovered that the concentration of amino acids decreased -&nbsp; while levels of ketone bodies and insulin increased - in cattle with significant concentrations of methane. These changes occurred as cattle with high methane emissions actively utilized amino acids to replenish the energy lost during methane production.



"Our results suggest that physiological differences and liver transcriptomes could be applied to monitor the levels of methane emissions from Japanese Black steers," said Professor Roh. "We are hopeful the relationship in this study leads to new perspectives."



The study is published in the journal <a href="https://www.nature.com/srep/">Scientific Reports</a>.



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

Study reveals features of cattle with high methane emissions

In a new study from Tohoku University, scientists have gained...

<a href="https://www.earth.com/news/seabirds-struggle-to-find-food-in-cloudy-ocean-water/">Birdwatching</a> has become an important form of ecotourism all over the world, generating significant revenue for local communities at birding hotspots. Birders are often willing to pay high prices to see rare or iconic species, and will travel from afar to find specific types of birds. In the past, birdwatching required only a pair of binoculars or a spotting scope, but today many birdwatchers enjoy photographing the birds, particularly at their nests. Since this is a delicate time of a bird’s life, the disturbance has led to questions about whether the mantra “take only photographs, leave only footprints” is quite as eco friendly as it sounds.&nbsp;



According to Xiaocai Tan, an ornithologist and PhD candidate at Guangxi University in China, this focus on birds’ nests has worried scientists, who are concerned that the close proximity of humans to the nesting sites might stress the birds and negatively impact their reproductive success. She and her colleagues decided to study the effect of photographers on the nesting success of birds in the Nonggang National Nature Reserve (NNNR) in southern China. This reserve has 90 percent forest coverage and is rich in birdlife, including seven species that are globally threatened.&nbsp;



Since the 2008 discovery of the Nonggang babbler, Stachyris&nbsp; nonggangensis, the area has become a hotspot for birdwatching tourism, and attracts an increasing number of bird photographers. These photographers wait in groups at the nest sites for several hours to get good images of birds. Nests that are photographed are visited by between 3 and 10 people during the day. Local guides have set up blinds made of dark-colored material, 5–10 m from the nests, and observers stay within these structures. Photography occurs every day and throughout the day (6:00–18:00&nbsp;​h), unless there is strong wind or rain.



During the field work for this project, the researchers monitored 277 different bird nests belonging to 42 species. They recorded nesting success at nests where photographers were able to visit (83 nests), and compared this with the success at nests where no photographers were allowed (194 nests). Previous research in the Reserve had shown that nest predators, including other birds, mammals and reptiles, killed around 60 percent, and sometimes up to 75 percent, of the nestlings in the region, including the young of the globally vulnerable Nonggang Babbler.&nbsp;



The researchers also recorded the feeding frequency of parent birds at nests with and without photographers. They did this for the five species of birds in the Reserve that are most commonly photographed at their nests.&nbsp;



The results, published in the journal <a href="https://avianres.biomedcentral.com/">Avian Research</a>, showed that, contrary to expectations, the predation rate of nests that were photographed (13.3 percent), was significantly lower than the rate seen in nests that were not photographed (62.9 percent). While birds often flush and fly away when a person comes near, it seems that in this case the visiting photographers were doing more to scare away the common nest predators than the nesting birds themselves. This finding applied both to nests where eggs were being incubated, and to those where nestlings were present.&nbsp;



The scientists found no significant differences between parental feeding rates at nests that were disturbed by photographers and nests that were undisturbed.&nbsp;



"In other words, the presence of the photographers increased the survival rate of the bird nestlings. Interestingly, their presence had little effect – positive or negative – on the feeding rates in those nests," said Tan.



According to Aiwu Jiang, the investigator who led the study, this finding is totally contrary to what most scientists had expected. “Like a scarecrow, the presence of photographers seems to scare the nest predators away. Other research we’ve conducted in the same area shows that the presence of traffic noise can draw away birds’ mammalian predators.”



“Although this finding suggests that photography has a positive impact on the successful breeding of birds, it doesn’t mean that we are encouraging photographers to visit nest sites – there needs to be further assessment of other aspects of nesting, and other kinds of stress responses, before the total effect of bird photography can be understood.”



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

How bird photographers improve nesting success

Birdwatching has become an important form of ecotourism all over...

A dramatic decline in <a href="https://www.earth.com/news/pesticide-exposure-dramatically-reduces-wild-bee-populations/">bee populations</a> at fruit farms in New Jersey and Pennsylvania has led scientists wonder whether these changes are just natural fluctuations, or warnings regarding significant future threats to the global food supply. Since the study has been conducted over an eight-year period (2005 to 2012), it is not possible to clearly conclude whether this decline represents a true drop in bee numbers, or only a normal variation over a larger cycle.&nbsp;



“This study is important because it is one of the first to assess trends in wild bee abundance in an agricultural system, where bees are providing an economically important ecosystem service,” said lead author Andrew Aldercotte, a doctoral candidate in Ecology and Evolution at <a href="https://www.rutgers.edu/">Rutgers University</a>. “Despite widespread recognition of the need for long-term monitoring of pollinator abundances and pollination service provision, such studies are exceedingly rare.”



“We saw two things come out,” Aldercotte added. “One was that the rate of visitation by bees was really low for the last two years of the study. But we also saw that the numbers bounced around a lot from year to year.”



The scientists analyzed data collected at 19 commercial farms in central New Jersey and eastern Pennsylvania during peak bloom periods from 2005 to 2012, focusing on pollination visits by 73 species of bees (including wild bees, bumblebees, and honey bees) to the flowers of watermelon plants. The analysis reveled that pollination of watermelon flowers by wild bees and bumblebees declined by more than half during that period, while the population of honey bees – which are not native to those regions and are managed in hives by farmers – remained largely stable.



“Data collectors watched flowers for periods of 45 seconds and wrote down every bee visit they observed and then moved on and observed another flower for a period of 45 seconds,” Aldercotte said. “And they kept doing that throughout the day.”



While in New Jersey the bee populations were still sufficient to pollinate crops, studies of other crops in different parts of the country show that insufficient pollination often reduce crop production. Further longitudinal studies are needed to clarify whether the population of bees overall is declining or if these drop in numbers reflect a natural variation over time.



The study is published in the journal <a href="http://dx.doi.org/10.1111/icad.12589">Insect Conservation and Diversity</a>.&nbsp;



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

Dramatic decline in bee populations observed in the U.S.

A dramatic decline in bee populations at fruit farms in...

<a href="https://www.earth.com/news/chimpanzees-use-surprisingly-complex-vocal-sequences/">Chimpanzees</a> don’t only forage for fruit. From time to time they also hunt smaller monkeys in the canopy in order to acquire protein-rich meat. Since these monkeys are usually very agile, chimpanzees are most successful in catching them by having their conspecifics hunt alongside them. 



According to a team of researchers led by the <a href="https://www.uzh.ch/en.html">University of Zurich</a> (UZH) and <a href="https://www.tufts.edu/">Tufts University</a>, chimpanzees often use communication to coordinate their cooperative behavior during hunting. By producing a specific type of vocalization called a “hunting bark,” they manage to recruit more group members to the hunt, which helps them capture their prey more efficiently.



The scientists studied over 300 hunting events recorded during the last 25 years at the Kanyawara chimpanzee community in Uganda, and discovered that, by making bark vocalizations, the wild apes catalyze group hunting. “Chimps who produce hunting barks provide information to those nearby about their motivation to hunt, and this information may persuade reluctant individuals to join, boosting the overall chances of success,” explained study lead author Joseph Mine, a doctoral student in Comparative Language Science at UZH.



Since hunting monkeys in dense tropical rainforests where visibility is significantly restricted is challenging, vocal communication allows chimpanzees to be more efficient. “Strikingly, following the production of hunting barks, we observed more hunters joining, greater speed in beginning the chase, and a shorter time to make the first capture,” said study senior author Zarin Machanda, an expert in Chimpanzee Behavioral Ecology at Tufts University.



While it is clear that such vocal communication makes hunting more effective, more research is needed to clarify why barks have this effect. “At the moment it is still unclear if these barks are given intentionally to coordinate the precise actions of the group, or whether they simply advertise an individual’s decision to hunt, which in turn, increases the likelihood of others joining them, and with more hunters they are more effective,” said study co-author Simon Townsend, an associate professor of Animal Communication at UZH.&nbsp;



This study suggests that the relationship between group communication and cooperation – which is fundamental in humans and led to the emergence of language and the complex forms of cooperation modern humans engage in – has very deep evolutionary roots. &nbsp;“Our results indicate that the relationship between vocal communication and group-level cooperation is ancient. This link seems to have been in place for at least seven million years, since our last common ancestor with chimpanzees,” Mine concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1126/sciadv.abo5553">Science Advances</a>.



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

Chimpanzees use vocal communication to coordinate hunting

Chimpanzees don’t only forage for fruit. From time to time...

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

[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

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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



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Two distant planets may be "water worlds"

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

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



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



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



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



Video Credit: NASA Goddard&nbsp;



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



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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



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

Satellites capture the world's biggest and fastest waves

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



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



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



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



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



Video Credit: European Space Agency&nbsp;



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

Satellites have become essential to our survival

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