As we continue to explore the cosmos, we are discovering an increasing number of exoplanets that could potentially <a href="https://www.earth.com/news/nasa-finds-17-exoplanets-that-have-oceans-and-possibly-alien-life/" target="_blank" rel="noreferrer noopener">harbor life</a>. One such world is K2-18 b, an exoplanet that has recently captured the attention of astronomers due to the presence of intriguing DMS gas molecules in its atmosphere.



<h2 class="wp-block-heading" id="h-carbon-footprints-found-on-k2-18-b">Carbon footprints found on K2-18 b</h2>



In September 2023, Nikku Madhusudhan, an astronomer at the <a href="https://www.cam.ac.uk/" target="_blank" rel="noreferrer noopener">University of Cambridge</a>, announced a <a href="https://www.earth.com/news/does-exoplanet-k2-18-have-the-right-conditions-to-support-alien-life/" target="_blank" rel="noreferrer noopener">very intriguing discovery</a>. 



Using the powerful James Webb Space Telescope (<a href="https://webb.nasa.gov/" target="_blank" rel="noreferrer noopener">JWST</a>), Madhusudhan and his team detected the presence of carbon-bearing molecules, including methane and carbon dioxide, on exoplanet K2-18 b. 



This discovery was added to other <a href="https://hubblesite.org/contents/news-releases/2019/news-2019-50" target="_blank" rel="noreferrer noopener">recent studies</a> suggesting that K2-18 b could be a Hycean exoplanet, characterized by a hydrogen-rich atmosphere and a water ocean-covered surface.



"Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere," explained Madhusudhan, the lead author of the paper announcing these results. 



"Traditionally, the search for life on exoplanets has focused primarily on smaller rocky planets, but the larger <a href="https://www.earth.com/news/new-class-of-exoplanets-discovered/" target="_blank" rel="noreferrer noopener">Hycean worlds</a> are significantly more conducive to atmospheric observations," he continued.



<h2 class="wp-block-heading" id="h-tantalizing-hint-of-dimethyl-sulfide-dms">Tantalizing hint of dimethyl sulfide (DMS)</h2>



The initial Webb observations also provided a possible detection of a molecule called dimethyl sulfide (DMS). On Earth, this molecule is "only produced by life", primarily by <a href="https://www.earth.com/news/plankton-tiny-ocean-creatures-overlooked-critical-life-on-earth/" target="_blank" rel="noreferrer noopener">phytoplankton</a> in marine environments. 



The abundance of methane and carbon dioxide, along with the shortage of ammonia, support the hypothesis that K2-18 b may have a water ocean underneath a hydrogen-rich atmosphere.



"It was a real shock, I had sleepless nights for a week," enthused Dr. Madhusudhan, recalling the moment when the analysis showed a possible hint of DMS in the planet's atmosphere. "That week, I didn't even muster the courage to break it to my own team."



<h2 class="wp-block-heading" id="h-why-a-whiff-of-dms-made-astronomers-look-again">Why a whiff of DMS made astronomers look again</h2>



Dimethyl sulfide (DMS) is an organic compound with the chemical formula (CH3)2S. This colorless, flammable liquid possesses a characteristic odor often associated with the smell of the ocean. 



DMS plays a crucial role in the Earth's sulfur cycle and has garnered significant attention due to its potential as a biomarker for extraterrestrial life.



<h3 class="wp-block-heading" id="h-biological-significance-of-dms-on-earth">Biological significance of DMS on Earth</h3>



On Earth, dimethyl sulfide is predominantly produced by marine organisms, particularly <a href="https://www.earth.com/news/marine-plankton-hold-a-long-record-of-ocean-health/" target="_blank" rel="noreferrer noopener">phytoplankton</a>. These tiny, photosynthetic organisms release DMS as a byproduct of their metabolic processes. 



When DMS enters the atmosphere, it undergoes oxidation, contributing to the formation of cloud condensation nuclei. This process influences cloud formation and, consequently, Earth's climate.



<h3 class="wp-block-heading">DMS as a biomarker for extraterrestrial life</h3>



Detecting DMS on distant exoplanets presents numerous challenges. The molecule's spectral signature is difficult to distinguish from other compounds, and its presence in an atmosphere may be masked by other gases. 



The detection of DMS in the atmosphere of an exoplanet, such as K2-18 b, has significant implications for the search for extraterrestrial life. 



On Earth, DMS is exclusively produced by biological processes, making it a compelling biomarker. The presence of DMS in an exoplanet's atmosphere suggests the possibility of marine life similar to Earth's <a href="https://www.earth.com/news/rising-temperatures-may-flip-plankton-into-carbon-emitters/" target="_blank" rel="noreferrer noopener">phytoplankton</a>.



<h2 class="wp-block-heading" id="h-k2-18-b-an-exoplanet-like-no-other">K2-18 b: An exoplanet like no other</h2>



K2-18 b orbits the cool dwarf star K2-18 in the <a href="https://www.earth.com/news/study-expands-the-habitable-zone-where-we-may-find-alien-life/" target="_blank" rel="noreferrer noopener">habitable zone</a>, approximately 120 light-years from Earth in the constellation Leo. With a radius 2.6 times that of Earth, K2-18 b is unlike anything in our solar system. 



These <a href="https://www.earth.com/news/neptune-like-exoplanets-atmospheres-interesting-earth-size-neighbors/" target="_blank" rel="noreferrer noopener">sub-Neptune exoplanets</a> are poorly understood, and the nature of their atmospheres is a matter of active debate among astronomers.



"Although this kind of planet does not exist in our solar system, sub-Neptunes are the most common type of planet known so far in the galaxy," explained team member Subhajit Sarkar of <a href="https://www.cardiff.ac.uk/" target="_blank" rel="noreferrer noopener">Cardiff University</a>. 



"We have obtained the most detailed spectrum of a habitable-zone <a href="https://www.earth.com/news/planetary-migration-model-explains-super-earths-and-sub-neptunes/" target="_blank" rel="noreferrer noopener">sub-Neptune</a> to date, and this allowed us to work out the molecules that exist in its atmosphere," Sarkar concluded.



<h2 class="wp-block-heading" id="h-cosmic-detective-story-continues">Cosmic detective story continues</h2>



The team is now conducting follow-up research with the JWST's <a href="https://webb.nasa.gov/content/observatory/instruments/miri.html" target="_blank" rel="noreferrer noopener">MIRI</a> (Mid-Infrared Instrument) spectrograph, hoping to further validate their findings and provide new insights into the environmental conditions on K2-18 b. 



The inference of DMS on the exoplanet, though incredibly tantalizing, requires further validation. As Madhusudhan explained, "Upcoming Webb observations should be able to confirm if DMS is indeed present in the atmosphere of K2-18 b at significant levels."



"Our ultimate goal is the identification of life on a <a href="https://www.earth.com/news/super-earth-discovered-in-the-habitable-zone-of-its-star/" target="_blank" rel="noreferrer noopener">habitable exoplanet</a>, which would transform our understanding of our place in the universe," concluded Madhusudhan. "Our past findings and future studies are a promising step towards a deeper understanding of Hycean worlds in this quest."



<h2 class="wp-block-heading" id="h-implications-of-finding-life-on-k2-18-b">Implications of finding life on K2-18 b</h2>



As we stand on the precipice of a potentially transformational discovery, the tantalizing hint of alien life on K2-18 b reminds us of the boundless possibilities that await us in the vast expanse of the universe. 



The tireless efforts of astronomers like Nikku Madhusudhan and his team, coupled with the unparalleled capabilities of the Webb Telescope, bring us closer than ever to answering one of humanity's most profound questions: Are we alone? 



As we eagerly anticipate the upcoming observations and the revelations they may bring, we find ourselves inspired by the relentless curiosity and unwavering dedication of those who seek to unravel the mysteries of the cosmos, pushing the boundaries of our understanding and redefining our place in the universe.



The full study was published in <a href="https://iopscience.iop.org/journal/2041-8205" target="_blank" rel="noreferrer noopener">The Astrophysical Journal Letters</a>.



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Webb studies planet K2-18 b again to confirm presence of gas ‘only produced by life’

As we continue to explore the cosmos, we are discovering an increasing number of exoplanets that could potentially harbor life. One such world is K2-18 b, an exoplanet that has recently captured the attention of astronomers due to the presence of intriguing DMS gas molecules in its atmosphere. Carbon footprints found on K2-18 b In September 2023, Nikku Madhusudhan, an astronomer at the University of Cambridge, announced a very intriguing discovery. Using the powerful James Webb Space Telescope (JWST), Madhusudhan and his team detected the presence of...

Tropical <a href="https://www.earth.com/news/plants-with-short-lives-are-more-sensitive-to-climate-change/">plants</a> with thick leaves will likely respond very successfully to rising levels of atmospheric carbon dioxide, according to a new study from the <a href="https://www.washington.edu/">University of Washington</a>.

The researchers found that competition between species, as well as multiple changes in the plant leaves, could preserve the ability of tropical forests to absorb CO2 from the atmosphere. 

It is difficult for scientists to predict how various plant species will respond to rising levels of carbon dioxide, particularly in the tropics. There will be both advantages and disadvantages, and the resulting shifts in vegetation will have a big influence on the future direction of climate change.

The UW team analyzed how tropical forests, which absorb large amounts of carbon dioxide, will respond as atmospheric CO2 levels continue to rise. 

"Our findings suggest that plants with some types of responses, like making their leaves thicker, will ultimately grow better in tropical forests than their competitors," said study senior author Professor Abigail Swann. 

"If these better-growing plants become more common in the forest, the total rates of water and carbon exchange could stay closer to what they are now."

In previous work, Professor Swann and colleagues showed that the CO2-related thickening of tropical plant leaves could worsen climate change, considering that thicker leaves may also be smaller. 

As a result of smaller leaves, plants would capture less sunlight for photosynthesis, absorb less carbon dioxide, and emit less water vapor - factors that all promote global warming. 

The new study expands on the earlier research to account for competition between plant species, and the ratio of carbon and nitrogen in the plants' leaves. 

While more carbon dioxide makes photosynthesis easier, the plants become less efficient at producing energy if nitrogen cannot keep pace with their growth rates. 

Professor Swann said that the verdict is still out on why exactly plants grow thicker leaves under high CO2 levels. However, the results of the modeling study indicate that there may be a simple explanation..

"Thicker leaves can concentrate the nitrogen so that photosynthesis rates per area of leaf are high," explained Professor Swann.

The study authors ran simulations for broad-leaf evergreen tropical trees, such as wild cashew and Ecuador laurel. The trees were programmed to have various responses to the higher carbon dioxide levels, and could compete with one another for space.

The study revealed that trees which were simulated to have more carbon relative to nitrogen in their leaves became less efficient at photosynthesis and emitted less water vapor. 

On the other hand, tree species with leaves that also thickened during the simulations were better at absorbing carbon and producing water vapor, helping them grow tall and stay cool. These trees could also outcompete their neighbors.

"Our work suggests that by shifting which plants are growing in the forest there may be less dire consequences of higher CO2 than other studies have suggested," said Professor Swann. 

"There is a lot we still don't know about how plants are responding to climate change -- this work really sets up some best guesses about which plants will grow best in future tropical forests that we can test with more observations."

The study is published in the journal <a href="https://agupubs.onlinelibrary.wiley.com/journal/19449224">Global Biogeochemical Cycles</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Tropical trees with thick leaves may thrive in higher CO2 conditions

Tropical plants with thick leaves will likely respond very successfully...

A fast-spreading <a href="https://www.earth.com/news/fiber-may-help-control-inflammation-in-covid-19-patients/">COVID-19</a> variant was already present in 15 countries before it was discovered, according to a new study from <a href="https://www.utexas.edu/">UT Austin</a>. The experts report that the highly contagious variant B117 was spreading throughout the United States for months by the time it was identified in the United Kingdom.

Study co-author Lauren Ancel Meyers is the director of the COVID-19 Modeling Consortium and a professor of Integrative Biology at the University of Texas at Austin.

"By the time we learned about the U.K. variant in December, it was already silently spreading across the globe," said Professor Meyers. "We estimate that the B117 variant probably arrived in the U.S. by October of 2020, two months before we knew it existed."

The researchers evaluated the likelihood that travelers from the U.K. introduced the variant into 15 countries between September 22 and December 7, 2020. Their analysis showed that the virus variant had almost certainly arrived in all of the 15 countries by mid-November. In the United States, evidence suggests that the variant had arrived by mid-October.

"This study highlights the importance of laboratory surveillance," said Professor Meyers. "Rapid and extensive sequencing of virus samples is critical for early detection and tracking of new variants of concern."

The experts have developed a new tool to help the U.S. expand national surveillance of variants. The online calculator indicates the number of virus samples that must be sequenced in order to detect new variants when they first emerge. 

"Health officials are looking for better ways to manage the unpredictability of this virus and future variants," said study co-author Spencer Woody. "Our new calculator determines how many positive SARS-CoV-2 specimens must be sequenced to ensure that new threats are identified as soon as they start spreading."

According to Woody, the calculator can also help labs figure out how quickly they will detect new variants, given their current sequencing capacity.

"We created this tool to support federal, state and local health officials in building credible early warning systems for this and future pandemic threats," said Professor Meyers.

A recent study published in the journal Nature found that the B117 COVID-19 variant may pose a 61 percent higher risk of mortality within 28 days. A separate investigation published in the BMJ drew a similar conclusion, reporting that B117 increases the risk of 28-day mortality by up to 64 percent.

"SARS-CoV-2 appears able to mutate quickly, and there is a real concern that other variants will arise with resistance to rapidly rolled out vaccines," said Dr. Leon Danon of the University of Bristol. 

"Monitoring for new variants as they arise, measuring their characteristics and acting appropriately needs to be a key part of the public health response in the future."

The UT Austin study is published in the journal <a href="https://wwwnc.cdc.gov/eid/">Emerging Infectious Diseases</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Highly contagious COVID-19 variant went undetected for months

A fast-spreading COVID-19 variant was already present in 15 countries...

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

The hidden diversity of coral species could help save them

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

A dangerous type of toxin is being emitted from pond scum, according to a study published by <a href="https://taylorandfrancis.com/">Taylor and Francis</a>. For the first time, scientists have detected the presence of anatoxin-a (ATX) in the atmosphere near a pond in Massachusetts with large algae blooms.

Anatoxin-a, also known as "Very Fast Death Factor," is a neurotoxin produced naturally by cyanobacteria in water bodies worldwide. ATX can cause a range of symptoms including loss of coordination, muscular twitching, and respiratory paralysis. The toxin can be fatal to dogs, livestock, and other animals who drink contaminated water.

Harmful algal blooms emerge when large amounts of cyanobacteria grow on the surface of a pond or lake, and these blooms are amplified by fertilizer runoff from wastewater or nearby farm fields. Cyanobacteria, which are also called blue-green algae, are a type of bacteria that can photosynthesize.

Algae blooms can further degrade water quality by depleting it of oxygen. When the algae eventually die, they sink to the bottom of the water and decompose. This process can consume all of the oxygen, killing fish and other animals. In addition, the toxins released from the algae blooms can prove fatal for marine life. 

"ATX is one of the more dangerous cyanotoxins produced by harmful algal blooms, which are becoming more predominant in lakes and ponds worldwide due to global warming and climate change," said study lead author Dr. James Sutherland.

The researchers speculated that ATX may become airborne under certain environmental conditions, even though it had never been detected in the atmosphere before.

To investigate, the team collected samples of airborne particles from around the edge of Capaum Pond on Nantucket Island from July to October, when it was regularly covered with algae blooms.

An analytical technique called liquid chromatography-tandem mass spectrometry was used to search for ATX in the samples, as well as in samples of water from the pond.

Anatoxin-a was consistently detected in the pond water at concentrations of up to 21ng/mg. On one occasion, it was also detected in the air around the pond.

According to the researchers, the neurotoxin was likely blown from the surface of the water by strong wind the previous night. Then, ATX could have persisted in the foggy conditions that were present the day that it was detected. 

The airborne source of ATX is not yet clear. The toxins could be released into the air within small water droplets, attached to aerosol particles, or even inside cyanobacteria blown into the air. The potential impacts on humans and wildlife are also unknown, but the possibility of exposure is cause for concern and further investigation.

"People often recreate around these lakes and ponds with algal blooms without any awareness of the potential problems," said Dr. Sutherland. "Direct contact or inhalation of these cyanotoxins can present health risks for individuals, and we have reported a potential human health exposure not previously examined."

The study is published in the journal <a href="https://www.tandfonline.com/toc/ulrm20/current">Lake and Reservoir Management</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Algae blooms can release neurotoxins into the air

A dangerous type of toxin is being emitted from pond...

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

Greater sage-grouse populations have declined by 80 percent

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

Despite claims that the negative impacts of pesticides are declining, researchers have discovered that the <a href="https://www.earth.com/news/it-pays-off-to-read-labels-and-avoid-products-with-harmful-chemicals/">chemicals</a> have become even more damaging over the past 25 years. 

Experts at the <a href="https://www.uni-koblenz-landau.de/en">University of Koblenz-Landau</a> report that while there has been a decrease in the amount of pesticides used, they have become increasingly toxic to plants and insects. 

The team demonstrated that the applied pesticide toxicity in agriculture increased substantially between 2004 and 2016. The researchers even found this pattern in genetically modified crops that were designed to reduce the environmental impacts of pesticides.

The results of the study clearly show that even in the two most important genetically modified crops in the U. S. - corn and soybean - the applied toxicity increases at the same rates as conventional crops.

"We have taken a large body of pesticide use data from the U.S. and have expressed changes of amounts applied in agriculture over time as changes in total applied pesticide toxicity," said study lead author Professor Ralf Schulz. "This provides a new view on the potential consequences that pesticide use in agriculture has on biodiversity and ecosystems".

The amount of insecticides used for agricultural activities in the United States decreased by more than 40 percent between 1992 and 2016. As a result, fish, mammals, and birds face lower applied toxicities compared to the 1990s.

Meanwhile, pollinators and other insects experienced double the toxicity between 2005 and 2015, as pesticide use shifted toward pyrethroid and neonicotinoid insecticides. 

According to the study authors, their findings likely apply to many other regions dominated by modern agriculture, though often the data for a thorough evaluation of trends in applied toxicity are not publicly available.

"These results challenge the claims of decreasing environmental impact of chemical pesticides in both conventional and GM crops and call for action to reduce the pesticide toxicity applied in agriculture worldwide," said Professor Schulz.

The study is published in the journal <a href="https://www.sciencemag.org/">Science</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Pesticides have become increasingly toxic to insects

Despite claims that the negative impacts of pesticides are declining,...

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

African elephants only inhabit a small part of their potential range

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

In a new study led by <a href="https://www.cornell.edu/">Cornell University</a>, experts have found that <a href="https://www.earth.com/news/offshore-wind-farms-europe/">farms</a> have been an average of 21 percent less productive over the last six decades as a result of climate change. According to researchers, this is equivalent to completely losing the last seven years of growth in agricultural productivity.

The results of the study suggest that global agriculture is becoming increasingly vulnerable to the effects of climate change, and warmer locations like Africa and Latin America are being hit the hardest. In these regions, growth in agricultural productivity has already been cut by up to 34 percent. 

The experts developed an all-encompassing econometric model to quantify the effect of human-caused climate change on what economists call "total factor productivity," a measure of the overall productivity of the agricultural sector.

"Our study suggests climate and weather-related factors have already had a large impact on agricultural productivity," said Professor Robert Chambers of the University of Maryland. "We used the model in this paper to estimate what total factor productivity patterns would have looked like in the absence of climate change."

Study lead author Ariel Ortiz-Bobea is an associate professor in the Charles H. Dyson School of Applied Economics and Management at Cornell.

"We find that climate change has basically wiped out about seven years of improvements in agricultural productivity over the past 60 years," said Professor Ortiz-Bobea. "It is equivalent to pressing the pause button on productivity growth back in 2013 and experiencing no improvements since then. Anthropogenic climate change is already slowing us down."

According to Professor Ortiz-Bobea, the team considered more than 200 systematic variations of the econometric model, and the results remained largely consistent. 

"When we zoom into different parts of the world, we find that the historical impacts of climate change have been larger in areas already warmer, including parts of Africa, Latin America and Asia."

Humans have already altered the climate system, said Professor Ortiz-Bobea, as climate science indicates the globe is about one degree Celsius warmer than without atmospheric greenhouse gases.

"Most people perceive climate change as a distant problem. But this is something that is already having an effect. We have to address climate change now so that we can avoid further damage for future generations."

The study is published in the journal <a href="https://www.nature.com/nclimate/">Nature Climate Change</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Climate change has cut agricultural productivity by 21 percent

In a new study led by Cornell University, experts have...

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

Hippos and whales evolved their hairless skin independently

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

In the past, melting <a href="https://www.earth.com/news/lakes-on-the-greenland-ice-sheet-are-draining-in-the-winter/">ice</a> sheets pushed up the sea level by as much as 18 meters, according to a new study led by <a href="https://www.dur.ac.uk/">Durham University</a>. The experts found that the sea level rose by about 6 meters per century during past warming events.

The research provides new insight into the potential consequences of climate change, especially if it continues at the current rate without mitigation. 

The team analyzed geological records of past ocean levels to determine which ice sheets were responsible for rapid sea-level rise. The investigation revealed that at the end of the last ice age around 14,600 years ago, the sea level rose at ten times the current rate due to Meltwater Pulse 1A (MWP-1A).

Prior to this analysis, it was widely believed that the Antarctic Ice Sheet was responsible for rapid sea-level rise at the end of the last ice age. The new study shows that most of the meltwater appears to have originated from the former North American and Eurasian ice sheets, with minimal contribution from Antarctica.

"Despite being identified over 30 years ago, it has been surprisingly challenging to determine which ice sheet was the major contributor to this dramatic rise in sea levels," said study lead author Yucheng Lin.

"Previously, scientists tried to work out the source of the sea-level rise based on sea-level data from the tropics, but the majority of those studies disagreed with geological records of ice sheet change."

"Our study includes novel information from lakes around the coast of Scotland that were isolated from the ocean due to land uplift following the retreat of the British Ice Sheet, allowing us to confidently identify the meltwater sources."

The freshwater that dumped into the ocean was comparable to melting an ice sheet twice the size of Greenland in only 500 years. The event disrupted ocean circulation, which in turn modified the climate. 

Now that experts know the source of the meltwater, they can improve the accuracy of climate models that are used to predict future changes based on the past. The findings are particularly important with the rapid retreat of the Greenland ice sheet.

"The technique we have used allows us to really dig into the error bars on the data and explore which ice-melt scenarios were most likely," explained study co-author Dr. Pippa Whitehouse.

"We found that most of the rapid sea-level rise was due to ice sheet melt across North America and Scandinavia, with a surprisingly small contribution from Antarctica.

"The next big question is to work out what triggered the ice melt, and what impact the massive influx of meltwater had on ocean currents in the North Atlantic. This is very much on our minds today - any disruption to the Gulf Stream, for example due to melting of the Greenland Ice Sheet, will have significant consequences for the UK climate."

The study is published in the journal <a href="https://www.nature.com/ncomms/">Nature Communications</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The sea level rose by 18 meters after the last ice age

In the past, melting ice sheets pushed up the sea...

For the first time, researchers have confirmed that <a href="https://www.earth.com/news/hundreds-of-northern-lakes-will-permanently-lose-their-ice-cover/">lakes</a> on the Greenland Ice Sheet drain enormous amounts of water, even during the wintertime. The new study from the <a href="https://www.cam.ac.uk/">University of Cambridge</a> raises new concerns about how fast the ice sheet is flowing into the ocean. 

The investigation was focused on radar data from a European Space Agency satellite. The experts found that even without heat from the Sun, lakes on the Greenland Ice Sheet often discharge large amounts of water to the base of the ice sheet. 

The "drainage events" are thought to play a significant role in accelerating the movement of the ice by lubricating it from below.

"Glaciers slow down in the winter, but they're still moving," said study co-author Dr. Ian Willis. "It must be this movement that causes fractures to develop in certain places allowing some lakes to drain." 

"We don't yet know how widespread this winter lake drainage phenomenon is, but it could have important implications for the Greenland Ice Sheet, as well as elsewhere in the Arctic and Antarctic."

The experts developed a new approach to detect changes in the lakes during the winter, when Greenland is in near-total darkness. This method uses the radar "backscatter," which is the reflection of waves back to the satellite from where they were emitted.

The study revealed that even in the depths of the Arctic winter, large amounts of surface lake water periodically cascade to the base of the ice sheet.

"One of the unknowns in terms of predicting the future of the ice sheet is how fast the glaciers move - whether they will speed up and if so, by how much," said Dr. Willis.

"The key control on how fast the glaciers move is the amount of meltwater getting to the bottom of the ice sheet, which is where our work comes in."

Lakes form on the Greenland Ice each summer. While the lakes can persist for weeks or even months, they can also drain in a matter of hours due to hydrofracturing. 

The draining lakes transfer millions of cubic meters of water and heat to the base of the ice sheet. According to the experts, affected areas include sensitive regions of the ice sheet interior where the impact on ice flow is potentially large.

"It's always been thought that these lakes drained only in the summer, simply because it's warmer and the sun causes the ice to melt," said study co-author Corinne Benedek. 

"In the winter, it's dark and the surfaces freeze. We thought that the filling of the lakes is what caused their eventual drainage, but it turns out that isn't always the case."

The researchers analyzed data from the Sentinel-1 satellite, which uses a type of radar called synthetic aperture radar (SAR). Over three winters, the team identified six lakes which appeared to drain over the winter months. 

"The first lake I found was surprising," said Benedek. "It took me a while to be sure that what I thought I was seeing was really what I was seeing." 

"We used surface elevation data from before and after the events to confirm what we were thinking. We know now that drainage of lakes during the winter is something that can happen, but we don't yet know how often it happens."

The study is published in the journal <a href="https://www.the-cryosphere.net/">The Cryosphere</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Lakes on the Greenland Ice Sheet are draining in the winter

For the first time, researchers have confirmed that lakes on...

<a href="https://www.earth.com/news/plants-have-a-memory-of-drought/">Plants</a> play a major role in cycling toxic mercury through the environment. This discovery was made by researchers at the <a href="https://www.uml.edu/">University of Massachusetts Lowell</a> while they were studying mercury gas in the atmosphere. The team found that a large amount of mercury is absorbed by plants and then deposited into soils.

Each year, hundreds of tons of mercury are emitted into the atmosphere from industrial activities, such as burning coal and mining, and also from natural processes.

Mercury emissions are absorbed by plants in a process that is similar to how they take up carbon dioxide. After the plants shed their leaves or die, and the mercury is transferred into soils, it can make its way into watersheds where it becomes a threat to wildlife and people who eat contaminated fish.

Study lead author Professor Daniel Obrist is an expert on mercury cycling within the environment. He explained that exposure to high levels of mercury over long periods of time can lead to neurological and cardiovascular problems in humans.

For the current investigation, the researchers analyzed more than 200 published studies with data on mercury levels in vegetation across more than 400 sites worldwide.

The analysis revealed that about 88 percent of the mercury found in plants was absorbed from the atmosphere. According to study co-author Jun Zhou, vegetation can take up more than 1,300 tons of mercury each year globally, which accounts for 60 to 90 percent of that which is deposited over land.

"When I walk outside here in New England, I am always amazed at the greenness of our forest, grasslands and salt marshes," said Professor Obrist. "One goal of my research is to determine how strongly vegetation controls the cycling of elements - some of which can be toxic pollutants - so we can better mitigate damaging effects."

Zhou noted that the research moves scientists toward a greater understanding of how mercury cycling works.

"Researchers have worked on the role that vegetation plays on cycling of mercury for over 30 years now, but the full extent of these impacts are still not yet fully realized," said Zhou.

"It was timely to write this comprehensive review and communicate to colleagues and the public about the current state of knowledge in this area."

The study is published in the journal <a href="https://www.nature.com/natrevearthenviron/">Nature Reviews Earth &amp; Environment</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Plants play a major role in mercury cycling

Plants play a major role in cycling toxic mercury through...

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

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

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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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.esa.int/">European Space Agency</a> features Kainji Lake, a reservoir on the Niger River.



In 1968, Kainji Lake was created by the construction of the Kainji Dam. The Niger River, the third longest in Africa, enters the lake in the north.&nbsp;



According to <a href="https://www.earth.com/news/rivers-in-the-american-west-are-a-lifesaving-resource-for-birds/">ESA</a>, the creation of the lake submerged Foge Island and the town of Bussa and permanently flooded other riverine settlements, leaving around 50,000 people displaced.&nbsp;



Large parts of Foge Island are temporarily exposed during low water tides, and the land is often used by migrating fishermen. Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria. 



Wild mammals occur at relatively low densities due to illegal hunting. Lake Kainji has suffered a dramatic decline as a fishery due to the high numbers of artisanal and subsistence fisherfolk using the lake. It has been suggested that a period of closure, together with controlled fishing rights may help improve fish stocks.



Kainji Lake National Park is the oldest of its kind in Nigeria. The park contains three distinct areas: a part of the Kainji Lake, the Borgu Game Reserve to the west of the lake, and the Zugurma Game Reserve to the southeast. The park is home to around 65 mammal species, 350 bird species, and 30 species of reptiles and amphibians. 



Video/ Image Credit: European Space Agency&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.

Kainji Lake in north central Nigeria

[sendtonews key="iuA5mpp3jv-1641775-12187" type="single"] Today’s Video of the Day from the...

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Today’s Video of the Day from <a href="https://www.igb.illinois.edu/">Carl R. Woese Institute for Genomic Biology</a> reveals how scientists can modify common crops like soybean, rice, and wheat to protect them from heat stress.



“We need to double crop production by 2050 to feed a growing global population, and not only are we not on track to do that, but climate change is further complicating things,” said Amanda Cavanagh, a lecturer at the University of Essex. 



The study is part of Realizing Increased Photosynthetic Efficiency (RIPE), an international research project that aims to develop food crops that turn the sun’s energy into food more efficiently.



“Using an engineering approach we designed multiple alternative metabolic pathways to photorespiration. Testing them in the field showed increases in productivity which led Amanda to significantly move the project forward by showing our engineered plants can withstand pretty extreme temperature stress,” said study co-author and RIPE researcher Paul South.&nbsp;



“As the climate changes and temperature stresses increase the pressure on our global food supply, farmers will need every tool available including engineering approaches like the synthetic biology used here to maintain safe and productive harvests.”



The experts tested plants modified to have more efficient photorespiration to see if they were better adapted to warmer temperatures.&nbsp;



The team found that the engineered plants produced 26 percent more biomass than the wild-type plants exposed to the same temperatures, and had 15 percent less yield loss under the higher temperatures.



Video Credit: Amanda Nguyen/University of Illinois



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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.

Designing crops that can beat the heat

[sendtonews key="QGPzYnXEtN-1712599-12187" type="single"] Today’s Video of the Day from Carl...

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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

[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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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes the first comprehensive estimate of carbon density in the Saharan, Sahel, and Sudanian zones of Africa. In an effort to measure the amount of carbon stored across these drylands, a team of scientists used high-resolution satellite images and artificial intelligence to map nearly 10 billion individual trees. 



"The high spatial resolution (50 cm) combined with AI and field measurements used in this study is key to improving tree inventories in drylands," said Pierre Hiernaux, a French researcher working for NASA. "The ever-increasing availability of very high-resolution satellite imagery will make it possible to assess carbon pools and their dynamics at the individual tree level on a global scale."



"This study is exceptional because it is pioneering a type of approach that will revolutionize the monitoring of trees and forests on a global scale: in the short term, it will be possible to map the world's trees from the centre of the Amazon to our schoolyards," said <a href="https://www.inrae.fr/en">INRAE</a> researcher Jean-Pierre Wigneron.



"Many fields of application will become much more efficient and accurate, such as tracking carbon stocks, biodiversity, monitoring logging and protection against illegal forest degradation, in near real time.”



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.

Remote sensing will revolutionize the way we monitor trees

[sendtonews key="EjmSP20gQK-2593093-12187" 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 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



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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://www.nasa.gov/goddard">NASA Goddard</a> features a visual dataset of.methane emissions from wetlands across the globe. Atmospheric methane levels have reached record highs in recent years, and wetlands are a major source of these emissions.&nbsp;



"Methane is an important greenhouse gas that contributes substantially to global warming. On a molecule by molecule basis, methane is much more efficient at trapping heat than carbon dioxide, the main driver of warming," says NASA.



"Though human activities, including agriculture, oil and natural gas production and use, and waste disposal, collectively contribute the majority of methane to the atmosphere, about a third of total methane emissions comes from wetlands."&nbsp;



According to NASA, understanding methane emissions from wetlands and other natural sources is critically important for scientists and policymakers who are working to combat climate change by reducing emissions from human activities.



Video Credit: NASA Goddard



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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.

Wetlands are a major source of methane emissions

[sendtonews key="f8fukm28Vz-2491833-12187" type="single"] Today's Video of the Day from NASA...

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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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Today’s Video of the Day from <a href="https://www.stowers.org/">Stowers Institute for Medical Research</a> describes why experts are studying zebrafish to gain a better understanding of how the immune system responds to injury. Zebrafish have the ability to repair and regenerate organs.



“Organ regeneration offers an exciting opportunity for studying the immune system and to inquire why some species can regenerate organs like the heart or missing limbs while others like humans cannot,” explained Dr. Tatjana Piotrowski.



Zebrafish sensory organ hair cells are an ideal system to investigate the pathways and cell types involved in regeneration since they are easily destroyed with antibiotics and begin regenerating within five hours. This enabled the researchers to identify the exact timing and genetic programs for each anti-inflammatory macrophage activation state.&nbsp;



“Our hypothesis is that human macrophages do not receive the proper chemical activation 'cocktail' to instruct pro-regenerative processes,” said Dr. Nicolas Denans. “Identifying the molecular recipe of macrophage activation in zebrafish may one day enable us to design regenerative immunotherapies in humans.”&nbsp;&nbsp;&nbsp;



“The new evidence is a valuable resource for comparative studies on the genetic programs involved in macrophage-mediated repair and regeneration. In other words, different types of injuries may induce different kinds of inflammatory responses. We want to decipher whether this 'language' is universal or if there are a variety of dialects."



Video Credit: Stowers Institute for Medical Research&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.

How the immune system responds to injury

[sendtonews key="0dEcERCq61-2283382-12187" type="single"] Today’s Video of the Day from Stowers...

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes how record-breaking heat expressed itself around the world in 2022.



Scientists have determined that 2022 was the 5th warmest year since 1880. Furthermore, the last nine consecutive years have been the warmest on record.



From devastating floods and wildfires to natural disasters like Hurricane Ian, 2022 showed us yet again how a warming climate affects people across the globe.&nbsp;



"As we look back at 20:22 and years past, we see that each year we better understand the challenges we face and how important it is to meet them," says NASA.



Video/ Image Credit: NASA Goddard



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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.

2022 illustrated the consequences of a warming climate

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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"

[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



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

Satellites reveal how Earth's systems are interconnected

[sendtonews key="JbW4VsY53O-1632195-12187" type="single"] Satellites reveal how Earth's systems are interconnected...

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



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



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



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



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



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



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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...