The Baltic Sea, one of the world’s youngest bodies of water, has long been known to host Atlantic and Baltic herring - plankton-eating fish critical to northern marine ecosystems.&nbsp;



Yet new research, published in the journal <a href="http://dx.doi.org/10.1038/s41467-024-55216-8" target="_blank" rel="noreferrer noopener">Nature Communications</a>, has uncovered a surprising adaptation in this environment: genetically distinct, fish-eating Baltic herring (Sardinops sagax caerulea). 



Conducted by scientists at <a href="https://www.uu.se/en" target="_blank" rel="noreferrer noopener">Uppsala University</a> in Sweden, the study challenges traditional assumptions about how Baltic herring evolved and found new ecological niches in brackish waters formed at the end of the last Ice Age.



<h2 class="wp-block-heading" id="h-herring-in-the-baltic-sea">Herring in the Baltic Sea</h2>



Herring serve a crucial function in the Atlantic Ocean and the <a href="https://www.earth.com/news/toxic-thallium-levels-are-rising-in-the-baltic-sea/" target="_blank" rel="noreferrer noopener">Baltic Sea</a>, transferring energy from plankton up the food chain to predatory fish, seabirds, marine mammals, and humans. 



Previous studies by the Uppsala group had already established that herring populations adapt genetically to variations in climate, salinity, and spawning seasons.&nbsp;



However, the newly discovered fish-eating Baltic herring adds an intriguing twist: these larger individuals exhibit distinct biological and genetic characteristics that set them apart from the traditional plankton-eating varieties.



<h2 class="wp-block-heading" id="h-the-baltic-herring-enigma">The Baltic herring enigma</h2>



Renowned Swedish taxonomist Carl Linnaeus once defined the Baltic herring as a subspecies of the Atlantic herring, specifically adapted to the Baltic’s brackish waters. Over the centuries, scientists have consistently noted how Baltic herring are generally smaller and contain less fat than their Atlantic relatives.&nbsp;



But when a local fisherman near Uppsala spoke of a large herring “that always spawns just before midsummer and which is as big as the Atlantic herring,” questions arose as to whether a previously unidentified herring population existed within the Baltic.



The study was led by Leif Andersson, a professor at the Department of Medical Biochemistry and Microbiology at Uppsala University.



“When I learned that the locals are aware of a specific population of very large Baltic herring that always spawns in the same area year after year, I decided to sample and explore their genetic constitution,” said Professor Andersson.&nbsp;



“Now we know that this is a genetically unique population that must have evolved over hundreds, if not thousands, of years in the Baltic Sea.”&nbsp;



<h2 class="wp-block-heading" id="h-switching-to-a-fish-based-diet">Switching to a fish-based diet</h2>



By collecting samples of these large herring, researchers noticed striking differences from the smaller, <a href="https://www.earth.com/news/plankton-at-risk-global-warming-threatens-the-oceans-lifeline/" target="_blank" rel="noreferrer noopener">plankton</a>-eating Baltic herring. 



Physical examinations, growth measurements, and fat-content analyses revealed that the larger herring contain higher levels of fat and show signs of damaged gill rakers - features aligning with a switch from filtering plankton to eating fish such as the common stickleback, which has sharp defensive spines.



According to the scientists, the relatively low dioxin content makes this fish-eating Baltic herring interesting for human consumption. With a faster growth rate and lower pollutant load, the fish-eating herring may offer both ecological and nutritional advantages.



<h2 class="wp-block-heading" id="h-uncovering-two-genetic-subpopulations">Uncovering two genetic subpopulations</h2>



Once it became clear that these larger Baltic herring were genetically distinct, the scientists expanded their focus, comparing samples of big herring from different Baltic locations. Whole genome sequencing confirmed that these fish fall into two separate subpopulations.



“Our genetic analysis demonstrates that there are at least two distinct subpopulations of fish-eating herring in the Baltic Sea; one occurs north of Stockholm, and the other occurs south of Stockholm,” said lead author Jake Goodall, a researcher at Uppsala University.&nbsp;



By identifying multiple genetic groups, the study reveals even greater diversity within the Baltic herring gene pool than previously thought.



<h2 class="wp-block-heading" id="h-why-fish-eating-herring-evolved-in-the-baltic">Why fish-eating herring evolved in the Baltic</h2>



The Baltic Sea, with salinity levels far lower than the Atlantic’s, has existed for only around 8,000 years. Such an environment is inhospitable to many <a href="https://www.earth.com/news/climate-change-disrupts-the-distribution-of-marine-species/" target="_blank" rel="noreferrer noopener">marine species</a>, and only a select few have successfully established populations there. 



The researchers propose that fish-eating herring have emerged due to a scarcity of competing predators, making it advantageous for some herring to exploit fish as a food source.



“We hypothesize that fish-eating Baltic herring have evolved due to a lack of competition from other <a href="https://www.earth.com/news/jellyfish-more-than-just-a-snack-for-predatory-fish/" target="_blank" rel="noreferrer noopener">predatory fish</a>, for instance, mackerel and tuna, which do not occur where we find fish-eating herring,” said Andersson.



“Thus, these herring take advantage of an underutilised food resource in the Baltic Sea.”



The ability to feed on smaller fish rather than plankton likely opened an ecological niche that larger herring could occupy, capitalizing on prey that other species could not exploit.



<h2 class="wp-block-heading" id="h-balancing-ecosystems-and-human-needs">Balancing ecosystems and human needs</h2>



The emergence of fish-eating Baltic herring underscores the Baltic Sea’s capacity to foster evolutionary innovations. As a keystone species, herring regulate energy flow in their ecosystem.&nbsp;



The discovery of these large, fish-feeding populations highlights the adaptability of herring to different diets, environmental pressures, and competition. It also suggests that such herring may provide a safer, fattier food option for consumers, given their comparatively lower dioxin levels.



These insights could inform <a href="https://www.earth.com/news/sustainable-fishing-gets-a-boost-from-genomics-roadmap/" target="_blank" rel="noreferrer noopener">fishery management</a> and conservation strategies, ensuring that as the Baltic continues to evolve, both ecosystem integrity and human consumption interests remain aligned.



<h2 class="wp-block-heading" id="h-rapid-evolutionary-change-of-baltic-herring-nbsp">Rapid evolutionary change of Baltic herring&nbsp;</h2>



Because the Baltic Sea is geologically recent, this discovery showcases how quickly species can adapt to novel conditions.&nbsp;



The fish-eating herring’s genetic distinctiveness, alongside significant physical and dietary differences, underlines the dynamic nature of evolution in brackish environments.&nbsp;



For scientists and policymakers, these findings serve as a reminder that even seemingly uniform species can harbor hidden diversity essential for resilience in changing waters.



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Rapid evolution in the Baltic Sea: How herring became fish-eaters

The Baltic Sea, one of the world’s youngest bodies of water, has long been known to host Atlantic and Baltic herring - plankton-eating fish critical to northern marine ecosystems.&nbsp; Yet new research, published in the journal Nature Communications, has uncovered a surprising adaptation in this environment: genetically distinct, fish-eating Baltic herring (Sardinops sagax caerulea).  Conducted by scientists at Uppsala University in Sweden, the study challenges traditional assumptions about how Baltic herring evolved and found new ecological niches in brackish waters formed at the end of the last...

A new study published in the journal <a href="http://dx.doi.org/10.1111/gcb.16368">Global Change Biology</a> has found that, without immediate and strong actions to mitigate climate change, global <a href="https://www.earth.com/news/value-freshwater-fish/">fish</a> supplies will not be able to be recover to sustainable levels. By projecting the impact that various global temperature rises and ranges of fishing activities would have on biomass (the amount of fish by weight in a specific area) from 1950 to 2100, the experts discovered that climate change has reduced fish stocks in 103 out of the 226 marine regions studied, and that these stocks will struggle to recover under most projected global warming levels over the 21st century.



“More conservation-oriented fisheries management is essential to rebuild over-exploited fish stocks under climate change. However, that alone is not enough,” said study lead author William Cheung, an expert in marine ecosystems at the <a href="https://www.ubc.ca/">University of British Columbia</a> (UBC). “Climate mitigation is important for our fish stock rebuilding plans to be effective.”



By using computer models to identify the climate change levels at which over-exploited fish stocks cannot rebuild, the scientists found that, if global temperatures exceed 1.8 degrees Celsius above pre-industrial levels, fish stocks will not be able to rebuild themselves. In a worst-case scenario (above 4.5 degrees warming), if people all over the world fished only three quarters of the annual sustainable catch, fish stock will still be unable to rebuild.



“Tropical ecoregions in Asia, the Pacific, South America and Africa are experiencing declining fish populations as species both move further north to cooler waters and are also unable to recover due to fishing demands,” Dr. Cheung said “These regions are the ones that feel the effects of global warming first and our study shows that even a slight increase of 1.5 degrees Celsius could have a catastrophic effect on tropical nations that are dependent on fisheries for food and nutrition security, revenue, and employment.”&nbsp;



In a scenario in which nothing is done to mitigate global warming and overfishing beyond sustainable targets occurs, global fish stocks are estimated to drop to 36 percent of the current levels. Sadly, due to climate change, the world is unlikely to ever return to historical levels of fish stocks.



“We are at a turning point. What we need is a coordinated global effort to develop practical and equitable marine conservation measures to support effective biomass rebuilding under climate change. These need to recognize the ways that marine biodiversity contributes to livelihood and economies, particularly in tropical marine ecoregions, as well as requiring more stringent limits on fishing activities to achieve greater biomass rebuilding potential,” Dr. Cheng concluded.



---



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;

Without strong action, global fish stocks could collapse

A new study published in the journal Global Change Biology...

Coral reefs are highly productive ecosystems that have come under threat in recent decades as a consequence of <a href="https://www.earth.com/news/past-variability-may-help-forests-cope-with-climate-change/">climate change</a>. This has fueled a surge in research on the basic biology of corals with a view to restoring reefs that have been damaged by ocean heating and acidification. Reef restoration depends on the successful recruitment of juvenile corals and this is difficult to quantify using current 3D modeling techniques because the juveniles are so very small and cryptic.&nbsp;



This problem has led marine biologist Dr. Kate Quigley to develop a new method for monitoring coral size and growth that relies on the use of dental scanning equipment. Digital 3D scanning is commonly used in dentistry and implant manufacturing because measurements need to be accurate right down to the μm scale in order to produce highly accurate molds. Intraoral dental scanners are also safe to use on live tissue, whereas previous 3D modeling methods often involved destroying the corals in order to measure them.&nbsp;



Dr. Quigley, a senior research scientist at the Minderoo Foundation, has published details of the new method in the journal <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1111/2041-210X.13959">Methods in Ecology and Evolution</a>. She was inspired to develop the new scanning method by a visit to her dentist.&nbsp;



During her visit, Dr. Quigley remarked on the similarities between coral and human teeth – both being calcium-based and requiring measuring tools that can withstand wet surfaces. “One day, I was at the dentist, and they rolled out this new scanning machine. I knew immediately that it was something that could apply to scanning very small corals given that corals and teeth actually share many similar properties. The rest is history!”



Although the older technologies involved in 3D modeling of coral reefs have seen substantial improvement and development in the recent past, they are really only applicable to objects in the size range of meters to centimeters. They lack capability in the millimeter and micron (μm) size range, which is what is necessary when measuring the early life stages of corals. Understanding the critical life stage of juvenile coral allows scientists to predict ecosystem changes, the impacts of disturbance and the potential for reefs to recover.



“At the moment, it is difficult to accurately measure very small objects in 3D, especially if you are interested in measuring small live animals, like coral, without hurting them. During my PhD it would take half a day to produce one scan, and I was interested in scanning hundreds of corals at a time," said Dr. Quigley.



To assess the effectiveness of these dental scanners, namely the ITero Element 5D Flex, Dr. Quigley measured juvenile corals from different species and size classes. The corals were originally collected from the Great Barrier Reef Marine Park and included species with complex branching morphology, as well as those with simple branching and those that have a flatter, encrusting life form. The trial was conducted at the National Sea Simulator at the Australian Institute of Marine Science, where the corals were temporarily removed from their indoor aquarium to have their surface areas and volumes scanned.&nbsp;



On average it took less than three minutes to scan and build a model of each individual coral compared to over four hours with previous methods – a 99 percent decrease in the time required to carry out such measurements. Dr. Quigley recorded equally fast and precise performances when measuring and comparing models of dead skeletons and living coral tissue, thus removing the need to sacrifice live animals in order to take measurements.



“For the first time, this new method will allow scientists to measure thousands of tiny corals fast, accurately and without any negative health impacts on the coral. This has the potential to expand large-scale monitoring of ocean health and for up-scaling coral reef restoration.”



While this is a huge improvement in terms of cutting down the time involved to monitor these small marine animals, the technology can only be used to make measurements out of the water. The scanning instrument is not waterproof and it relies on the use of lasers. In addition, the 3D scans still need to be processed manually, which is a slow process. Dr. Quigley hopes to create an automatic analysis pipeline from scanning to measurement in future, potentially using AI.



“Potentially the scanner could be made completely waterproof. However, it is unclear how well the laser technology would work completely submerged underwater. We have taken this technology on the boat before and brought up wild and laboratory-reared corals for measurement, so we are getting there!”



“The pairing of both rapid data acquisition and processing in this way has the potential to significantly improve our understanding of coral biology for pressing questions around conservation in this important biological system.”



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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

Dental scanning equipment helps monitor young corals

Coral reefs are highly productive ecosystems that have come under...

Over and under highway <a href="https://www.earth.com/news/losing-wildlife-will-be-very-costly-for-some-countries/">wildlife</a> crossings are designed to help animals move safely across roadways. It's an attempt to maintain animal movement and genetic connectivity. However, we are now learning about another benefit of these crossings.&nbsp;



A recent study published in the <a href="https://journals.sagepub.com/doi/full/10.1177/03611981221108158">Transportation Research Record</a> found that wildlife crossings in Washington state save approximately $235,000 to $443,000 every year per structure. The state has 22 wildlife bridges and underpasses.&nbsp;



The researchers found that every year, there are one to three fewer wildlife collisions per mile in a 10-mile radius around each wildlife crossing.



"Wildlife crossing structures not only benefit the ecosystem but may also improve road safety," said study author Wisnu Sugiarto, an economics doctoral student at <a href="https://wsu.edu/">Washington State University</a>.



Evidence suggests that other states,&nbsp; including North Carolina, Utah, and Wyoming, also experience fewer wildlife collisions due to wildlife crossing structures.



Sugiarto analyzed accident data from the Washington State Department of Transportation from 2011 to 2020 and information associated with 13 bridges and underpasses in the state. The study compared collisions before and after the crossings were built. He also analyzed another area in the state that never had crossings for a control.&nbsp;



The most common crossings are wide bridges and underpasses, with the bridges being much more expensive. Although bridges may be more expensive, they may also be more effective. Sugiarto found that bridges led to a more significant reduction in wildlife collisions because deer, the animal most likely to be involved in a crash, prefer bridges to underpasses.&nbsp;



Many wildlife collisions occur due to simple misfortune. The drivers often drive safely but happen to be in the wrong place at the wrong time.&nbsp;



"We often talk about things that we can and cannot control," said Sugiarto. "From a driver point of view, they may choose to drive safely, but still, unfortunately, there are animals that cross the road, and they end up hitting them. This shows there's something we can do about these collisions."



The good news is that we may begin to see more of these bridges across the country in the future, thanks to the federal Infrastructure Investment and Jobs Act of 2021, which allocates $350 million to a Wildlife Crossing Pilot Program.&nbsp;



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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

Wildlife crossings save lives and money in Washington state

Over and under highway wildlife crossings are designed to help...

An international team of paleontologists led by <a href="https://vt.edu/">Virginia Tech</a> has recently discovered, named, and described a new sauropodomorph – a long-necked <a href="https://www.earth.com/news/new-impact-crater-dates-back-to-the-end-of-the-dinosaurs/">dinosaur</a> – which is, thus far, the oldest dinosaur skeleton ever found in Africa. The almost intact skeleton of Mbiresaurus raathi&nbsp;was found in northern Zimbabwe over the course of two digging operations, in 2017 and 2019. The creature is estimated to have been six feet long and to weigh between 20 and 65 pounds.



“The discovery of&nbsp;Mbiresaurus raathi&nbsp;fills in a critical geographic gap in the fossil record of the oldest dinosaurs and shows the power of hypothesis-driven fieldwork for testing predictions about the ancient past,” said study lead author Christopher Griffin, a former PhD student in Geology at Virginia Tech.



“These are Africa’s oldest-known definitive dinosaurs, roughly equivalent in age to the oldest dinosaurs found anywhere in the world. The oldest known dinosaurs — from roughly 230 million years ago, the Carnian Stage of the Late Triassic period — are extremely rare and have been recovered from only a few places worldwide, mainly northern Argentina, southern Brazil, and India.”



“Early dinosaurs like&nbsp;Mbiresaurus raathi&nbsp;show that the early evolution of dinosaurs is still being written with each new find and the rise of dinosaurs was far more complicated than previously predicted,” added study co-author Sterling Nesbitt, an associate professor of Geosciences at Virginia Tech.



The discovery of M. raathi – alongside a larger assortment of Carnian-aged fossils – sheds new light on dinosaur migration. Like all continents, Africa was once part of the supercontinent called Pangea, characterized by a climate divided into strong humid and arid latitudinal belts, with more temperate belts spanning higher attitudes and vast deserts extending across the lower tropics.



“Because dinosaurs initially dispersed under this climatic pattern, the early dispersal of dinosaurs should therefore have been controlled by latitude,” Dr. Griffin explained. “The oldest dinosaurs are known from roughly the same ancient latitudes along the southern temperate climate belt what was at the time, approximately 50 degrees south.” Zimbabwe – where M. raathi was discovered – falls along this climate belt, bridging a geographical gap between southern Brazil and India during the Late Triassic Age.



At the beginning, these dinosaurs were restricted by climatic belts to southern Pangea, and only later in history dispersed worldwide, during a period of intense worldwide humidity known as the Carnian Pluvial Event. After these migrations, barriers returned, mooring the dinosaurs in distinct provinces across Pangea for the remainder of the Triassic Period. Further research is needed to clarify the behavioral and migration patterns of M. raathi, as well as the role it played among the early dinosaurs.



The study is published in the journal <a href="https://www.nature.com/articles/s41586-022-05133-x">Nature</a>.



Image Credit: Virginia Tech



---



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;

Africa’s oldest known dinosaur recently discovered

An international team of paleontologists led by Virginia Tech has...

In many cases, return to office after lifting-off pandemic-related restrictions has disrupted the newly established close relationship between owners and their pets that emerged during lockdowns. Many people use pet cameras to find out what their furry friends have been doing in the house during office hours. However, such cameras are needed in every room and the footage needs to be reviewed afterwards. Now, a research team led by the <a href="https://www.gatech.edu/">Georgia Institute of Technology</a> has created a new device called PetTrack which, through a combination of sensors, can provide accurate, real-time indoor locations of the pets.



This revolutionary tracking device uses ultra-wideband (UWB) radio wireless sensors to locate the pet, and accelerometers to determine if it is sitting or moving, regardless of walls, furniture, or other objects that may be in the way. All of this is located on a small sensor which can be attached on a collar and can be viewed through a compatible smartphone application.



“PetTrack comprises two things: one is knowing the pet’s indoor location and second is trying to understand their activity,” said&nbsp;study senior author Ashutosh Dhekne, an assistant professor of Computer Science at Georgia Tech. “Together, combining where the pet is and what the orientation of the pet is, we can create a summary map of where the pet has been during the day and what activity the pet was doing.”



While this device is currently designed just to monitor an animal’s location and position, it could have many possible future applications. For instance, pet daycares could use it to enable owners to see how their pet is faring away from home. In addition, this technology could become a training tool where a buzzer could sound if a pet is in an area in which they are not supposed to be.



“We could use our existing setup to also track when pets make accidents in the house during potty training,” explained study lead author Neeraj Alavala, a Masters student at Georgia Tech. “We already have the technology to track when and where these accidents happen and can ensure that those areas get cleaned up. As an extension, we can also give the pet feedback like a buzzer to train the pet to not go in the house.”&nbsp;



“Overall, the idea is to connect better with your pet, using PetTrack. You could detect changing pet behaviors and interact with the pet using location-aware robotic toys,” Professor Dekhne concluded.



The study is published in the proceedings of the 2022 Workshop on Body-centric Computing Systems in Portland, Oregon and can be accessed <a href="https://dl.acm.org/doi/10.1145/3539489.3539587">here</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;

New device tracks location and activity of pets

In many cases, return to office after lifting-off pandemic-related restrictions...

A new study from the <a href="https://www.usf.edu/">University of South Florida</a> illustrates how climate-driven changes can have a cascading effect across ecosystems. The experts have discovered that as Florida’s climate becomes more tropical, oyster reefs are steadily being replaced by <a href="https://www.earth.com/news/floridas-mangroves-rising-sea-level/">mangrove</a> islands.



Study lead author Stephen Hesterberg was conducting fieldwork in Tampa Bay when he noticed that mangroves were overtaking most oyster reefs. This widespread transition poses a major threat to species which are dependent on oyster reef habitats, such as the American oystercatcher.



In collaboration with doctoral student Kendal Jackson and Professor Susan Bell, Hesterberg set out to investigate the extent and the cause of this habitat conversion. The researchers determined that warmer temperatures and fewer winter freezes had allowed mangrove islands to start taking over as the dominant salt marsh vegetation.&nbsp;



“Rapid global change is now a constant, but the extent to which ecosystems will change and what exactly the future will look like in a warmer world is still unclear,” said Hesterberg. “Our research gives a glimpse of what our subtropical estuaries might look like as they become increasingly 'tropical' with climate change.”



The analysis of aerial images - captured from 1938 to 2020 - revealed that 83 percent of the monitored oyster reefs in Tampa Bay had fully converted to mangrove islands. The experts also found that the rate of conversion accelerated throughout the 20th century.&nbsp;&nbsp;



According to Professor Bell, this study provides a unique opportunity to examine changes in adjacent coastal ecosystems and generate predictions of future oyster reef conversions. “As we change our climate, we see evidence of tropicalization – areas that once had temperate types of organisms and environments are becoming more tropical in nature."



While the transition to mangrove islands is already well-advanced in the Tampa Bay estuary and further south, Professor Bell said Florida ecosystem managers in northern coastal settings will face tropicalization within decades.



“The outcome from this study poses an interesting predicament for coastal managers, as both oyster reefs and mangrove habitats are considered important foundation species in estuaries,” said Professor Bell.



Oyster reefs provide coastal protection from flooding, improve water quality, and reduce shoreline erosion. As reefs transition to mangroves, these ecosystem services will be greatly limited or lost altogether.&nbsp;



It will become increasingly difficult to maintain oyster reefs in Florida's shifting climate, but human intervention could make it possible. In his new role as executive director of the nonprofit Gulf Shellfish Institute, Hesterberg will continue to investigate ways to restore oyster reefs to potentially avoid mangrove conversion.



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

Tropical climate is wiping out oyster reefs in Florida

A new study from the University of South Florida illustrates...

Human forearms are made out of two bones - the ulna and the radius. These bones are separated in humans, giving us a range of <a href="https://www.earth.com/news/predicting-the-movement-of-sea-lions-can-help-protect-them/">movement</a> that's lacking in many other creatures.&nbsp;



Goats, horses, and bats have semi-fused ulnae and radii, probably for running and flying, respectively. In frogs, these two forearm bones are completely fused, which is thought to be an adaptation for jumping. However, this explanation fails to consider the fullness of frog biodiversity.&nbsp;



“Many people think frogs jump, and a lot of them do. But there are also frogs that live their entire lives underground; there are frogs that glide; there are arboreal frogs that mostly climb like monkeys; there are frogs who primarily live underwater; and then there are frogs that just mostly walk. Frogs have evolved to move in so many ways, but the radius and ulna bones are always fused together,” explained Dr. Rachel Keeffe with the <a href="https://www.floridamuseum.ufl.edu/">Florida Museum of Natural History</a>.



Dr. Keeffe wondered if there was a better explanation for the forelimbs of frogs. For instance, during mating, male frogs clasp females with their forelimbs and also fight other males for access to females. These activities could explain the beefier forelimbs.&nbsp;&nbsp;



To test this idea, Dr. Keeffee used museum specimens to create forelimb models. She modeled the leg of a bullfrog, a frog known for its jumping prowess. Next, she developed other models with varying degrees of fusion between the ulnae and radii, including one model where the bones were separate, another where they were partially fused, and a third where there was a single bone.&nbsp;



Dr. Keeffee ran software simulations on these different models to mimic the stress of jumping. Other simulations were used to mimic the stress of mating on a forelimb.&nbsp;&nbsp;



Surprisingly, in both jumping and mating scenarios, less stress was put on the semi-fused model than on the fully fused forelimbs frogs possess.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;



Rather than disproving her hypothesis, Dr. Keeffee interprets her results as a sort of evolutionary compromise. Although the bones have more stress when they’re fused, these bones are thicker and lighter, possibly for better jumping.&nbsp;



As for mating, the stress is also more on the fused bones; however, with two unfused bones, the single tendon could be attached to only the ulna or radius, not both, making a weaker forearm than the fused bone. Dr. Keefe hopes to explore this idea with further model research.&nbsp;



This study was published in the <a href="http://dx.doi.org/10.1111/joa.13737">Journal of Anatomy</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

Why do frogs have fused forearms?

Human forearms are made out of two bones - the...

<a href="https://www.earth.com/news/wild-horses-have-higher-stress-levels-than-domestic-ones/">Horses</a> have been living together with human for thousands of years – a long co-evolution that helped them develop impressive social skills: they seem to be highly receptive to human emotions and are proficient at understanding human demands. A new study led by the <a href="https://www.utu.fi/en">University in Turku</a> in Finland has found that horses are often more reluctant in new situations if they have multiple riders, have had several owners, or have been with the current owner for just a brief period of time.&nbsp;



“Domestic horses may spend several hours daily in close contact with humans, which can affect horse welfare, physiology, and behavior. Therefore, it is important to understand which factors can influence the horses’ emotions during interactions with humans and what shapes their relationship - particularly in novel situations that can be very stressful to the animals,” said study lead author Océane Liehrmann, a doctoral student in Biology at the University of Turku.



The researchers recruited 76 privately owned horses from the Turku area and analyzed their reactions to novel objects. In a first experiment, the horses were led to walk on two surfaces which were new to them – a white tarp and a fluffy blanket – while in a second test, they were presented with a fluffy stuffed toy. In both cases, the horses had to interact either with their owner or a stranger.



“Interestingly, horses with an exclusive relationship with their owner were the calmest when approaching the novel surfaces and easily agreed to be touched with the toy. Horses that are regularly ridden or trained by different persons showed more stress behaviors in the test situations,” Liehrmann explained.



Moreover, the experiments revealed that horses with shorter relationships with their owners were more reluctant in new situations and seemed more stressed when asked to interact with unfamiliar objects or surfaces. By contrast, those that had at least six to eight years of relationship with their owner were usually very calm in novel situations. Horses older than 17 refused more often to step on the unfamiliar surfaces when led by a stranger, while they easily agreed to when led by their owners.



“Our findings suggest that a positive horse-human relationship may take time to develop as it is shaped by multiple factors, such as the horse’s previous interactions with humans. Overall, the results show that animals’ relationships with their human caretakers should be better considered in animal welfare and its research,” Liehrmann concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1016/j.applanim.2022.105709">Applied Animal Behavior Science</a>.&nbsp;&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;

Horses with a trusted owner remain calm in new situations

Horses have been living together with human for thousands of...

Not all microbes bring disease and discomfort for animals; in fact, many are very useful, or even essential for survival. Beetles of the genus Lagria are dependent on their symbiotic bacterial bodyguards for <a href="https://www.earth.com/news/coral-reproductive-capacity-decreases-with-depth/">reproductive</a> success, and therefore have to keep them close. This is not a simple matter as the beetles metamorphose completely during their life cycle, meaning that their tissues get reorganized, new organs develop and their exoskeletons get shed. All of this makes it difficult for the useful microbes to tag along to beetle adulthood.



Female beetles lay their eggs in humid soil, under leaf litter, where the eggs would certainly be colonized by fungi that are present among the decomposing leaves. This would lead to the decay and death of the eggs. Instead, a female carries several species of symbiotic bacteria in glands near the oviduct and, when she lays the eggs, bacteria get squeezed out and coat the surface of the eggs. These bacteria produce several types of antibiotic substances that protect the eggs, and then the larvae and pupae, from fungal colonization.&nbsp;



Until now, however, it has not been understood how the symbiotic bacteria remain with a beetle offspring as it changes through the egg, larva and pupa stages, such that the bacteria are present in the adult female’s reproductive organs when it is time for her to lay her own eggs. A new study by researchers from Germany and Denmark has now identified three unique storage pockets that are present, like backpacks, on the dorsal surface of each larva and that ensure the essential bacteria are carried along during the life cycle.&nbsp;



“Here we show how an insect can maintain beneficial microbial partners despite the drastic rearrangements of body structures that occur during metamorphosis,” said corresponding author Dr. Laura V. Flórez, a researcher at the Department of Plant and Environmental Sciences of the University of Copenhagen. “By modifying unique ‘pockets’ on their backs,&nbsp;Lagria&nbsp;beetles manage to keep their protective symbionts and facilitate their relocation, during pupation, to newly developed adult organs.”



Females of many&nbsp;Lagria&nbsp;species carry a mix of beneficial bacteria in their paired glands next to the oviduct. Antibiotics produced by the bacteria protect, the eggs, larvae, and pupae of the beetles against fungi. In one of the species studied here,&nbsp;L. villosa, the largest component of the symbiotic mix is a strain of Burkholderia bacteria called Lv-StB, which has lost the genes and cellular structures for motility, and probably can't survive for long outside the beetles.



Flórez and colleagues show, in their publication in the journal <a href="https://www.frontiersin.org/articles/10.3389/fphys.2022.979200/full">Frontiers in Physiology</a>, that&nbsp;L. villosa&nbsp;and&nbsp;L. hirta&nbsp;female pupae house their symbionts mostly inside the three two-lobed pockets on the back of the thorax, where they may be nourished by the beetles. Such ‘back pockets’ in larvae and pupae aren't known in any other insect. In female pupae, symbionts also congregate in a fourth spot, between bristles at the back of the head. The pockets are only vestigial in male pupae, and contain few or no symbionts. Clearly, the males have no role in laying eggs and therefore do not need to store useful bacteria for this purpose.&nbsp;



“The symbionts go from the highly exposed egg surface to colonize the pockets on the back of the larvae and pupae. Finally, they end up in specialized glands associated with the reproductive system of adult females,” summarized first author Rebekka S. Janke, a doctoral student at the Johannes Gutenberg University of Mainz.



But how, exactly, do the microbes get from the storage pockets on the pupa’s back, down to the genital organs at the tip of the abdomen of an adult female?&nbsp;



To answer this question, the experts scattered miniscule fluorescent beads, each only 1.0 μm wide, across the surface of early pupae. They found that, after the pupa had emerged, the majority of these beads ended up on the tip of the abdomen. The researchers conclude that the beads, like presumably the symbionts, are shuffled towards the genitals by friction during the emergence process. The mechanism by which the symbionts then colonize the accessory glands of females is not yet known.



“In the adult stage, the main purpose of the symbiotic organs seems to be to enable successful transmission onto the egg stage and to the next generation. Since only females lay eggs, male adults do not need to carry these potentially costly symbionts and are a dead-end for the bacteria,” explained Flórez.



“To better understand how beneficial symbionts are transmitted and maintained within and across generations, we'll need to identify which host and symbiont factors regulate symbiont establishment," said study co-author Dr. Martin Kaltenpoth. "For example, does the host select for specific symbionts? And through which mechanisms can immotile symbionts colonize the symbiotic organs?”



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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

Beetles have "backpacks" to protect their eggs

Not all microbes bring disease and discomfort for animals; in...

Social interactions between animals of the same species are often characterized by cooperation within groups and conflict or competition between groups. However, in certain circumstances, cooperation can arise between different social groups, such as is commonly apparent between groups of humans. Cooperation between groups is sometimes driven by the need for protection against common threats, such as predators, competitors or environmental hardships, but it can also be beneficial in securing access to scarce resources, such as females.&nbsp;



For a long time it was thought that intergroup cooperation was a behavior unique to humans as it has not been recorded among other social animals. However, a new study on male bottlenose <a href="https://www.earth.com/news/dolphins-have-accents-that-vary-by-region/">dolphins</a> in Australia has shown that they too benefit from maintaining multiple-level alliance networks between groups of associated individuals.&nbsp;



The research team, led by scientists from the <a href="https://www.bristol.ac.uk/">University of Bristol</a>, analyzed association and consortship data to model the structure of alliances between 121 adult male Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Shark Bay in Western Australia. The findings have been published in The Proceedings of the National Academy of Sciences (PNAS).



“Cooperation between allies is widespread in human societies and one of the hallmarks of our success. Our capacity to build strategic, cooperative relationships at multiple social levels, such as trade or military alliances both nationally and internationally, was once thought unique to our species," explained study co-lead author <a href="https://research-information.bris.ac.uk/en/persons/stephanie-l-king">Dr. Stephanie King</a>, an associate professor in Bristol’s&nbsp;<a href="http://www.bristol.ac.uk/biology/">School of Biological&nbsp;Sciences</a>.



The Bristol University scientists, along with colleagues from the University of Zurich and University of Massachusetts, found that male dolphins in Shark Bay form first-order alliances of two–three males and that these pairs or trios of unrelated males cooperate to herd individual females. Multiple first-order alliances (numbering 4-14 unrelated males) cooperate in teams to pursue and defend females, representing a second-order of alliances. In addition, multiple teams also work together, forming third-order alliances out of cooperating second-order alliances.&nbsp;



These findings indicate that dolphins make use of a complex, hierarchical social network system with cooperation between non-related individuals. Indeed, the researchers say that these dolphins exhibit the largest known multi-level alliance network of any non-human animal.&nbsp;&nbsp;



“Not only have we shown that male bottlenose dolphins form the largest known multi-level alliance network outside humans, but that cooperative relationships between&nbsp;groups, rather than simply alliance size, allows males to spend more time with females, thereby increasing their reproductive success," said Dr. King.



“We show that the duration over which these teams of male dolphins consort females is dependent upon being well-connected with third-order allies, that is, social ties&nbsp;between&nbsp;alliances leads to long-term benefits for these males," said Dr. Simon Allen, senior lecturer at Bristol’s School of Biological Sciences.



Intergroup cooperation in humans was thought to be unique and dependent upon two other features that distinguish humans from our common ancestor with chimpanzees - the evolution of pair bonds and parental care by males. “However, our results show that intergroup alliances can emerge without these features, from a social and mating system that is more chimpanzee-like,” noted Professor Richard Connor of the University of Massachusetts, who co-led the study with Dr. King.



The publication of the importance of intergroup alliances in dolphins in 2022 holds special significance as the team celebrates the 40th&nbsp;anniversary of the start of Shark Bay dolphin research in 1982, and the 30th&nbsp;anniversary of the publication in 1992 of their discovery of two levels of male alliance formation, also published in&nbsp;The Proceedings of the National Academy of Sciences.



“It is rare for non-primate research to be conducted from an anthropology department, but our study shows that important insights about the evolution of characteristics previously thought to be uniquely human can be gained by examining other highly social, large-brained taxa," explained study co-author Dr. Michael Krützen, head of the Anthropology Institute at the University of Zurich.



“Our work highlights that dolphin societies, as well as those of nonhuman primates, are valuable model systems for understanding human social and cognitive evolution," concluded Dr. King.



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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

Male dolphins form alliances to access females

Social interactions between animals of the same species are often...

Although leopard seals are some of Antarctica’s apex predators, their solitary habits and lethal reputation, combined with their habitat’s extreme <a href="https://www.earth.com/news/fish-die-offs-are-intensifying-with-climate-change/">climate</a>, make them one of the most difficult top predators to study on Earth. However, a research team led by <a href="https://www.baylor.edu/">Baylor University</a> has now attempted to shed more light on these fascinating creatures’ activities and behavioral patterns by studying 22 leopard seals off the Western Antarctica Peninsula, a region rapidly warming.



By weighing and measuring each seal and tracking their activities and diving patterns using satellite data and GPS tags, the scientists managed to document the flexible behaviors and traits which may offer leopard seals the necessary resilience to cope to Antarctica’s warming climate and environmental stresses.



“This study greatly increases our understanding of leopard seals’ life history, spatial patterns, and diving behavior,” said study lead author Sarah Kienle, an assistant professor of Biology at Baylor. “We show that these leopard seals have high variability (or, flexibility) in these different traits. Across the animal kingdom, variability is vital for animals adapting and responding to changes in their environment, so we’re excited to see high variability in this Antarctic predator.”



The analyses revealed that adult female leopard seals are 1.5 larger and longer than their male counterparts, an unusual phenomenon among marine mammals. According to the researchers, larger females may be better at defending feeding areas, and stealing prey from smaller seals. Moreover, they consume bigger, energy-rich prey, such as fur seals or penguins, while smaller females and males frequently eat smaller prey, like krill or fish.



Females also spend more time “hauled-out” on ice than males. For instance, two females spent two weeks hauled-out on ice in the middle of the ocean, without getting into the water or eating. The scientists argue that this two-week period is when female seals give birth and nurse their pups. Soon after, they wean their offspring and return to their usual activities.



Another interesting finding is that female and male leopard seals are capable of swimming both short and long distances in coastal, as well as open-ocean habitats. For example, one seal travelled only 46 kilometers from where the research team was located, while another one travelled 1,700 kilometers during the same period.



Finally, leopard seals of both sexes appear to be short, shallow divers, reaching an average of 30 meters deep during three-minute-long dives. However, there are exceptions too, with a male diving to 1,256 meters for 25 minutes.



“It’s interesting to see such variation [in movements and dive behavior] in a relatively small number of animals. To me, this means that leopard seals are highly flexible in their movement patterns, and that’s a really good thing in terms of adapting to changes in your environment,” Professor Kienle said.



In future research, the scientists aim to compare these leopard seals with other population across the Southern Ocean. “I have so many more questions, and I’m excited to continue learning about leopard seals for years to come. There’s so much more to discover about this incredible Antarctic predator,” Kienle concluded.



The study is published in the journal <a href="http://dx.doi.org/10.3389/fmars.2022.976019">Frontiers in Marine Research</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;

Scientists reveal new features of the elusive leopard seal

Although leopard seals are some of Antarctica’s apex predators, their...

As global temperatures have risen, so has the prevalence of <a href="https://www.earth.com/news/fish-worldwide-are-shockingly-vulnerable-to-climate-change/">fish</a> mass die-offs, according to a new study led by the <a href="https://www.uark.edu/">University of Arkansas</a>. Such catastrophic events can have severe impacts on the function of a variety of ecosystems, endangering fish populations and reducing the global food supply. The experts argue that the frequency of these events is steadily increasing, with potentially dire consequences for the whole world if greenhouse emissions are left unchecked.&nbsp;



The scientists compiled 526 documented cases of fish die-offs which occurred across the Minnesota and Wisconsin lakes between 2003 and 2013, and discovered that the main causes of these events were infectious diseases, summerkills, and winterkills. By narrowing their focus to summerkills – fish mass mortality linked to rising temperatures – they found a strong correlation between local air and water temperatures and the occurrence of such events. Their models that used either air or water temperature led to similar results – an important aspect, since air temperature data is more widely available globally than water temperature data.



After establishing a historical baseline, the researchers used air and water temperature-based models to estimate the frequencies of future summerkills. Local water temperature projection models estimated an approximate six-fold increase in the frequency of fish die-offs by 2100, while local air temperature projections predicted a staggering 34-fold increase.



“If there are eight summerkills per year now, the models suggest we could have about 41 per year based on water temperature estimates or about 182 per year based on air temperature estimates,” explained study lead author Simon Tye, a doctoral student in Evolutionary Ecology at the University of Arkansas.



“We think predictions from the water temperature model are more realistic, whereas predictions from the air temperature model indicate&nbsp;we need to better understand how and why regional air and water temperature estimates differ over time to predict how many mortality events may occur.”



Overall, the analysis revealed a strong correlation between rising temperatures and the frequency of ecological disasters. While the study only used data related to temperate northern lakes, the results could also apply to lakes in Arkansas. “One of the findings of the paper is that similar deviations in temperature affect all types of fish, such that a regional heatwave could lead to mortalities of both cold- and warm-water fish,” Tye said.



“Specifically, climate change is more than gradually increasing temperatures because it also increases temperature variation, such as we experienced much of this summer. In turn, our findings suggest these rapid changes in temperature affect a wide range of fish regardless of their thermal tolerance,” he concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1002/lol2.10274">Limnology and Oceanography Letters</a>.&nbsp;&nbsp;&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;

Fish die-offs are intensifying with climate change

As global temperatures have risen, so has the prevalence of...

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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

Detecting mercury contamination with the tap of a finger

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



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



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



Video Credit: ACS Reactions



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



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

How does salt makes things taste better?

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



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



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



Video/ Image Credit: ESA



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



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

Santiago, Chile in South America

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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

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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



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The province of Zaragoza in northeast Spain

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

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> 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

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

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Pyrenees Mountains, which form a natural boundary between France and Spain in southwest Europe.



The mountain range is 430 kilometers in length. It stretches from the Mediterranean Sea on the east to the Atlantic Ocean on the west.



At an elevation of 3404 meters, Pico de Aneto is the highest mountain peak in the Pyrenees, and the third-highest peak in Spain. Pico de Aneto is located in the Posets-Maladeta Natural Park, which spans more than 82,000 acres.&nbsp;



"Geological studies have revealed that the Pyrenees Mountains have been around for longer than the Alps, with their sediments first deposited in coastal basins during the Paleozoic and Mesozoic eras," reports ESA.



"The entire mountain range formed due to the upwelling of large sedimentary rocks by the collision of the Iberian and the Eurasian plate around 100 to 150 million years ago, followed by intense erosion from ice and water."



The western Pyrenees receive more precipitation due to moisture blowing in from the Atlantic Ocean. The mountain range contains many lakes, several small glaciers, and some of the highest waterfalls in Europe.



Video &amp; Image Credit: ESA



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



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

The Pyrenees Mountains in southwest Europe

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Earth,Like,Exoplanet,3d,Render

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes two exoplanets that are orbiting a star 218 light-years away. A team of researchers led by the University of Montreal has found evidence that these planets are "water worlds."



The experts used data from NASA’s Hubble and Spitzer Space Telescopes. They discovered that exoplanets Kepler-138 c and Kepler-138 could be composed largely of water.



"We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that's why we called them super-Earths," explained study co-author Björn Benneke.&nbsp;



"However, we have now shown that these two planets, Kepler-138 c and d, are quite different in nature and that a big fraction of their entire volume is likely composed of water. It is the best evidence yet for water worlds, a type of planet that was theorized by astronomers to exist for a long time."



Video Credit: NASA Goddard



Image Credit: NASA, ESA, and Leah Hustak (STScI)



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



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

Two distant planets may be "water worlds"

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



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



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



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



Video Credit: NASA Goddard&nbsp;



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



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

Satellites reveal how Earth's systems are interconnected

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Today’s Video of the Day from the <a href="https://welcome.miami.edu/">University of Miami</a> Rosenstiel School of Marine and Atmospheric Science explores how changes in water temperatures have affected tiger shark habitats and movements in the North Atlantic Ocean. The study reveals that rising temperatures have caused the sharks to shift toward the poles over the past 40 years.



“Tiger shark annual migrations have expanded poleward, paralleling rising water temperatures,” explained study lead author Neil Hammerschlag. “These results have consequences for tiger shark conservation, since shifts in their movements outside of marine protected areas may leave them more vulnerable to commercial fishing.”



The researchers analyzed nine years of tracking data from satellite-tagged tiger sharks, combined with four decades of conventional tag and recapture data provided by National Oceanic and Atmospheric Administration (NOAA) Cooperative Shark Tagging Program.



The experts found that during the last decade of record heat, for every one-degree Celsius increase in water temperatures, tiger sharks migrated further poleward by over 400 kilometers. They also migrated two weeks earlier than usual to waters off the northeastern coast of the United States.



“Given their role as apex predators, these changes to tiger shark movements may alter predator-prey interactions, leading to ecological imbalances, and more frequent encounters with humans,” concluded Professor Hammerschlag.



Video Credit: University of Miami Rosenstiel School of Marine and Atmospheric Science



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



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

Tiger sharks are shifting poleward as temperatures rise

Today’s Video of the Day from the University of Miami...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> is focused on the melt ponds that emerge during the spring and summer on the Greenland Ice Sheet, which is the largest ice mass in the northern hemisphere.



"Melt ponds are vast pools of open water that form on both sea ice and ice sheets and are visible as turquoise-blue pools of water in this Copernicus Sentinel-2 image," says ESA.



"When snow and ice melts atop glaciers, water flows in channels and streams and collects in depressions on the surface. These melt ponds can speed up the melting of the surrounding ice since they greatly reduce the ice’s ability to reflect sunlight."



"This can create a positive feedback where an increasing number of melt ponds absorb more heat which causes ice cover to melt even faster."



According to ESA, Greenland has been hit with a late-season heatwave that began in early September. This caused the type of melt event that usually occurs in the middle of summer.



"In a recent paper published in Nature Climate Change, scientists found that major sea-level rise from the melting of the Greenland ice cap is now ‘inevitable’ even if the burning of fossil fuels were to halt overnight," says ESA. "Using satellite observations of Greenland ice loss and ice cap from 2000 to 2019, the team found the losses will lead to a minimum rise of 27 cm regardless of climate change."



Video Credit: ESA&nbsp;



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



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

Melt ponds on the Greenland Ice Sheet

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> describes a new map of Mars that is providing insight into the planet’s watery past. The map also reveals where future missions could safely land on Mars.&nbsp;



The map has been created over the last decade using observations of water-rich rocks and mineral deposits. The images were captured by ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter.



"A big surprise is the prevalence of these minerals, with the map revealing hundreds of thousands of water-affected locations in the oldest parts of the planet," says ESA. "The new data will help answer exciting questions about Mars’ climate history, whether water was globally persistent or confined to short, intense episodes, and whether the conditions were ever suitable for life."



"Specifically, the map shows the locations and abundances of aqueous minerals. These are from rocks that have been chemically altered by the action of water in the past, and have typically been transformed into clays and salts."



According to John Carter of the Institut d’Astrophysique Spatiale (IAS), our collective understanding of Mars has been oversimplified. He explained that planetary scientists have tended to think that only a few types of clay minerals on Mars were created during its wet period, then as the water gradually dried up, salts were produced across the planet.



The new map shows that the composition of Mars is much more complicated than what we thought. For example, while many salts formed after Martian clays, there are some salts that are presumed to be older than some of the clays.&nbsp;



“The evolution from lots of water to no water is not as clear cut as we thought, the water didn’t just stop overnight. We see a huge diversity of geological contexts, so that no one process or simple timeline can explain the evolution of the mineralogy of Mars. That’s the first result of our study. The second is that if you exclude life processes on Earth, Mars exhibits a diversity of mineralogy in geological settings just as Earth does,” said Carter.



Video Credit: ESA



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



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

The history of Mars is much more complex than we thought

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Today's Video of the Day from the <a href="https://www.stowers.org/">Stowers Institute for Medical Research</a> describes how cavefish adapted to a sedentary lifestyle over tens of thousands of years. 



The experts found that the muscle metabolism of cavefish has been genetically reprogrammed over time. As a result, the animals have experienced major changes in their morphology and behavior. Despite these changes, however, the cavefish remain healthy and fit.



The research may provide new clues about the evolutionary consequences of prolonged physical inactivity in humans.&nbsp;



“It’s no surprise that people are moving less and less as technology has advanced,” said Rohner. “With cavefish, we have a unique system where we can study what might happen if people remained couch potatoes over very, very long periods of time.”



Video Credit: Stowers Institute for Medical Research



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



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

Cavefish are healthy despite their sedentary lifestyle

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> some of the most incredible waves in the world, as seen by Landsat satellites.



"With more than 370,000 miles of coastline on Earth, there are plenty of places where epic waves build up, curl over, and hurtle toward the shore.- much to the thrill of surfers," says NASA. "There are some places where these waves are so magnificent that they can be seen from space."



"With the broad perspective of satellites, we can see how these iconic waves develop into the world’s tallest, longest, fastest, and heaviest."



Video Credit: NASA Earth Observatory&nbsp;



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



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...