Young aspen trees in Yellowstone are doing something they have not done in almost 100 years. Rather than sprouting and being eaten back to nubs by elk and bison, they're actually growing into tall, adult forest trees rising up towards the canopy.



This matters more than it might seem, because it shows what happens when a missing piece of an ecosystem returns.



<h2 class="wp-block-heading" id="h-yellowstone-aspens-and-elk">Yellowstone, aspens, and elk</h2>



In the 1920s, people <a href="https://www.yellowstone.org/wolf-project/" target="_blank" rel="noreferrer noopener">eliminated wolves in Yellowstone</a>. At the time, with limited scientific knowledge, managers believed it was the right thing to do.



<a href="https://www.earth.com/news/from-wolves-to-dogs-did-domestication-begin-without-human-help/">Without wolves</a>, elk herds grew very large. Elk love to eat aspen shoots - the tender young growth is highly palatable to them.



For roughly 70 years, elk browsed aspen sprouts down to stub height, and the trees couldn't grow. 



If you had walked through Yellowstone in the 1980s, you would have seen many tiny aspen shoots covering the ground, but almost no young trees gaining height. 



The forest's regeneration was stalled. Old trees died, and no new ones replaced them.



In 1995 and 1996, park managers reintroduced wolves into the <a href="https://www.earth.com/news/yellowstone-supervolcano-eruption-study-sparks-new-debate-on-where-and-when-it-will-erupt/">Yellowstone Park ecosystem</a>. Scientists hoped and wondered whether this would change anything for the trees.



<h2 class="wp-block-heading" id="h-why-aspen-matter-to-yellowstone">Why aspen matter to Yellowstone</h2>



Aspen groves provide habitat for many species. Birds nest in them. Beavers eat the bark and use the wood for dams. Butterflies and moths lay eggs on the leaves. 



Their canopy admits enough light for wildflowers and shrubs to grow beneath. When it rains, aspen groves hold water in the soil better than some other forest types.



In short, when aspen return, dozens of other species benefit. More trees support more insects, which in turn support more birds, enriching the ecosystem.



<h2 class="wp-block-heading" id="h-checking-the-trees-three-decades-later">Checking the trees three decades later</h2>



<a href="https://fwcs.oregonstate.edu/users/luke-painter" target="_blank" rel="noreferrer noopener">Luke Painter</a>, an ecologist at <a href="https://oregonstate.edu/" target="_blank" rel="noreferrer noopener">Oregon State University</a>, sought clear answers. His team returned to 87 aspen stands across Yellowstone that scientists had previously surveyed. 



They measured thousands of young trees, looked for bite marks, and counted how many stems were tall enough that elk could no longer reach the tips.



About a third of these stands now have many tall young aspens pushing toward the canopy. 



"About 26 of the 87 aspen stands we examined had large numbers of tall saplings throughout, a remarkable change from the 1990s when surveys found none at all," Painter said.



<h2 class="wp-block-heading" id="h-why-wolves-matter-to-yellowstone-aspens">Why wolves matter to Yellowstone aspens</h2>



Breaking it all down, the conclusions of this study are pretty simple. 



<a href="https://www.earth.com/news/wolves-move-pups-across-mountains-to-adapt-to-climate-pressure/">Wolves hunt elk</a>. When wolves came back, two things happened. First, elk numbers declined from unusually high levels. Second, elk changed their behavior. They spent less time in the same areas feeding.



With fewer elk and shorter feeding bouts, more aspen shoots survived long enough to exceed the browsing zone - about six to seven feet high. 



Once a sapling reaches that height, elk cannot easily reach the growing tip. The tree continues to grow.



"The reintroduction of large carnivores has initiated a recovery process that had been shut down for decades," Painter explained.



Scientists call this a <a href="https://www.nature.com/scitable/knowledge/library/trophic-cascades-across-diverse-plant-ecosystems-80060347/" target="_blank" rel="noreferrer noopener">trophic cascade</a> - when adding or removing one species causes changes that ripple through the whole system.



<h2 class="wp-block-heading" id="h-some-places-recover-others-don-t">Some places recover, others don't</h2>



Unfortunately, not every aspen stand has recovered yet. Some valleys still have many short, heavily browsed shoots, because it's not only elk eating them anymore. 



<a href="https://www.earth.com/news/yellowstones-iconic-bison-have-merged-into-a-single-herd/">Bison herds have grown</a>, and bison browse on aspen as well. They are strong enough to break young trees. 



"Increasing numbers of bison may be emerging as a new constraint to aspen in some areas," Painter confirmed.



Additionally, winter snow depth varies; droughts stress trees; bears and mountain lions also hunt elk; and hunting outside the park influences elk distribution. 



All of these factors interact, which is why some sites show strong recovery, others show moderate recovery, and a few have changed very little.



The key pattern is that places with many tall saplings experience little browsing, and aspen groves that remain popular eating grounds today stay short. 



This fact is the strongest indication that tree recovery is linked directly to wolf presence, not solely to weather or soil conditions.



<h2 class="wp-block-heading" id="h-proof-in-the-measurements">Proof in the measurements</h2>



Painter's team did not rely on casual observation. They used the same methods as earlier researchers, measuring the same plots. 



They counted recruitment - when young trees surpass browsing height and begin progressing toward maturity. This measure is crucial. Sprouts are insufficient if they never grow; without recruitment, the forest cannot replace itself.



The results are robust. After being stalled for most of a century, Yellowstone's aspens are increasing in height. In recovering stands today, you will see saplings - six, eight, or ten feet tall - that were not present in the 1990s.



<h2 class="wp-block-heading" id="h-the-future-of-yellowstone-s-aspens">The future of Yellowstone's aspens</h2>



"This is a remarkable case of <a href="https://www.earth.com/news/giant-viruses-found-in-yellowstones-hot-springs-may-be-near-the-root-of-all-life-on-earth/">ecological restoration</a>," Painter concluded. "Wolf reintroduction is yielding long-term ecological changes contributing to increased biodiversity and habitat diversity."



Trees grow slowly, so even with wolves restored, it will take decades for these young aspens to form a full-grown forest. 



Some areas might never fully recover if bison numbers continue to rise or if the climate becomes too hot and dry.



Thanks to the work of Painter and his team, scientists are now certain that restoring the Yellowstone predator has restarted aspen forest regeneration. Not everywhere and not perfectly, but enough to be measured, creating hope for the future.



The full study was published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S0378112725004499?via%3Dihub" target="_blank" rel="noreferrer noopener">Forest Ecology and Management</a>.



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Yellowstone's aspen trees are growing again thanks to the reintroduction of wolves

Young aspen trees in Yellowstone are doing something they have not done in almost 100 years. Rather than sprouting and being eaten back to nubs by elk and bison, they're actually growing into tall, adult forest trees rising up towards the canopy. This matters more than it might seem, because it shows what happens when a missing piece of an ecosystem returns. Yellowstone, aspens, and elk In the 1920s, people eliminated wolves in Yellowstone. At the time, with limited scientific knowledge, managers believed it was the right...

According to a <a href="https://www.noaa.gov/news-release/increase-in-atmospheric-methane-set-another-record-during-2021">preliminary analysis</a> led by the National Oceanic and Atmospheric Administration (<a href="https://www.noaa.gov/">NOAA</a>), increases in atmospheric methane hit a new record in 2021, averaging 1,895.7 parts per billion (ppb) during last year – which is 15 percent higher than in the 1984-2006 period, and around 162 percent greater than pre-industrial levels.



Although carbon dioxide remains the biggest contributor to anthropogenic global warming, methane is roughly 25 times more powerful at trapping heat in the atmosphere, and thus has a major short-term impact on the rate of <a href="https://www.earth.com/news/flash-droughts-are-coming-on-faster-due-to-climate-change/">climate change</a>. This gas is emitted by oil and natural gas production, as well as by livestock farming and wetlands, whose microbe-rich soils are ideal for naturally producing and emitting methane.



In November, 2021, over 100 countries signed a “<a href="https://www.state.gov/united-states-european-union-and-partners-formally-launch-global-methane-pledge-to-keep-1-5c-within-reach/">Global Methane Pledge</a>” to cut methane emissions by 30 percent until the end of this decade. However, some major emitters such as Russia and China have not signed this pledge yet, and NOAA’s analysis suggests that even in countries that signed it, the rates of emissions remain extremely high.&nbsp;&nbsp;



“Our data show that global emissions continue to move in the wrong direction at a rapid pace. The evidence is consistent, alarming, and undeniable,” said NOAA administrator Richard Spinrad. “Reducing methane emissions is an important tool we can use right now to lessen the impacts of climate change in the near term, and rapidly reduce the rate of warming.”



Since a large part of methane emissions originate from unintentional leaks from industrial wells and pipelines, fixing these problems should be relatively easy. “Reducing methane emissions from fossil fuel is an important step, and a low-hanging fruit to reduce atmospheric methane levels,” said Xin “Lindsay” Lan, a research scientist at NOAA’s <a href="https://gml.noaa.gov/">Global Monitoring Laboratory</a>.&nbsp;



“The latest increases in methane concentrations reinforce the critical importance of reducing human-caused methane emissions if we are going to slow the rate of increase in warming,” confirmed Steven Hamburg, a chief scientist at the <a href="https://www.edf.org/">Environmental Defense Fund</a>. “There is agreement in the scientific community that the majority of methane emissions are human caused and account for more than a quarter of the warming we are currently experiencing.”



However, other factors such as the massive rains in tropical areas that have flushed huge quantities of methane from wetlands, or the major role livestock play in methane emissions, could be more difficult to control and mitigate. Nevertheless, slashing these emissions as much as we can remains the fastest and cheapest way to reduce global warming in the short term.



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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

Methane emissions hit a new record in 2021

According to a preliminary analysis led by the National Oceanic...

Tanis, an important fossil site in North Dakota, has produced some fascinating findings. Previously at the site, scientists discovered sturgeon and paddlefish that died as Chicxulub - the <a href="https://www.earth.com/news/new-details-on-the-asteroid-impact-that-killed-the-dinosaurs/">asteroid</a> that killed the dinosaurs - hit Earth.&nbsp;



Lodged in the fishes gills are tiny spherules, particles created from molten rock that date to the impact. The fish seem to have inhaled these particles with their dying breath. It was through analyzing the growth patterns of these fish that scientists determined the <a href="https://www.earth.com/news/the-dinosaurs-died-in-the-springtime/">asteroid struck in springtime</a>.&nbsp;&nbsp;



Other fossils from the site have included a turtle impaled on a wooden stake, a pterosaur egg with embryo inside, small mammals along with their burrows and triceratops skin. Scientists believe that all of these amazing remains come from the moment of the asteroid impact.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;



Now, another spectacular and perhaps more momentous finding comes from Tanis. An incredibly well preserved dinosaur leg with impressions of skin including foot pads was found by a team led by Robert DePalma, a University of Manchester graduate student. The leg appears to be that of a thescelosaurus, according to professor Paul Barrett of London’s <a href="https://www.nhm.ac.uk/">Natural History Museum</a>.&nbsp;



"It's from a group that we didn't have any previous record of what its skin looked like, and it shows very conclusively that these animals were very scaly like lizards. They weren't feathered like their meat-eating contemporaries.” Barrett told BBC.&nbsp;



"This looks like an animal whose leg has simply been ripped off really quickly. There's no evidence on the leg of disease, there are no obvious pathologies, there's no trace of the leg being scavenged, such as bite marks or bits of it that are missing,"



Some scientists are suspicious of the claims at Tanis. For one thing, the entire site is a jumble of terrestrial and marine fossils from the western interior seaway mixed together, probably by the meteor impact. It’s possible that some of these animals died earlier and were mixed together after the impact. So far, the findings have not been presented in a peer reviewed scientific journal, and their scientific merit is yet to be confirmed.&nbsp;&nbsp;



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

Dinosaur fossil suggests it was killed by THE asteroid

Tanis, an important fossil site in North Dakota, has produced...

Although rain is essential for the survival of <a href="https://www.earth.com/news/invisible-flower-colors-help-plants-survive/">plants</a>, it also frequently carries harmful pathogens, such as bacteria, viruses, or filamentous fungi. A new study led by <a href="https://en.nagoya-u.ac.jp/">Nagoya University</a> in Japan has found that when plants are exposed to rain, hair-like structures on their leaves’ surface called trichomes recognize the rain as a risk factor for disease and promptly activate their immune systems to prevent or fight off infections.



Just like humans and other multicellular organisms, plants also have immune systems that help them detect pathogens and defend themselves against infections. To find out how plants respond to rain, the scientists conducted an experimental study using Arabidopsis thaliana&nbsp;seedlings. By performing RNA-sequencing analyses, they found that several major immune-related genes are expressed in response to rain. These genes are regulated by immunosuppressive genes called calmodulin-binding transcription activators (CAMTAs), which are controlled by calcium ions.&nbsp;



The researchers discovered that when the plants were exposed to rain, calcium ions levels around the trichomes on leaf surfaces increased, suggesting that trichomes can sense rain as a risk factor and induce calcium waves across the leaves to inactivate the immunosuppressor CAMTA and thus activate immune-related genes.&nbsp;



In order to confirm these findings, the researchers conducted similar experiments on Arabidopsis mutants which lacked trichomes. As they expected, the propagation of calcium waves was compromised in these mutants, and their immune responses were consequently dampened.&nbsp;



“From these results, we confirmed that trichomes play a role in sensing rain as a risk factor and activating immune responses,” said study senior author Yasuomi Tada, an associate professor of Genetics at Nagoya University. “Our findings suggest that we may be able to artificially improve plants’ defensive capabilities against diseases at any time and for any length of time. Using this technology, we could make it possible to activate crops’ immune responses when environmental conditions are harsh enough to possibly cause disease in plants, which could result in stable crop yields.”



The study is published in the journal <a href="https://www.nature.com/articles/s41467-022-28813-8">Nature Communications</a>.&nbsp;



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

Plants activate immune defenses against pathogens in rain

Although rain is essential for the survival of plants, it...

It’s strange that cacao, the main ingredient in chocolate, is central to a great mystery. For centuries, humans have grown and eaten cacao but somehow, we never understood one of the central processes that gave us such delicious food - its <a href="https://www.earth.com/news/bird-pollination-can-be-advantageous-for-plants/">pollination</a>.



Cacao flowers are tiny and the insects that gather on the tree are also miniscule and diverse, so it may be excusable that no one’s looked close enough at the right time to find a pollinator for cacao. Now, new research published in the journal <a href="https://besjournals.onlinelibrary.wiley.com/journal/26888319">Ecological Solutions and Evidence</a> examines the pollination of cacao.&nbsp;&nbsp;&nbsp;



In northern Peruvian dry agroforests - that is, cacao plantations grown in the shade of other trees - glue was applied to the flowers of the plant to see what insect visited. A variety of insects were caught, with 38% being aphids, 13% were ants and 10% were thrips. In wet agroforests of southern Peru, thrips made up 65% of the insects caught, midges were 14%, and parasitic wasps were 10% of visitors.&nbsp;



There was also a difference in the behavior of insects in these different habitats. In dry agroforests, more insects were found in the shade. In the wetter agroforests, however, insects preferred to be in the sun - at least during the rainy season when the research was carried out.&nbsp;



Interestingly, the cacao set fruit at a rate of just 2%, hand pollination was only able to raise this number to 7%. This baffled the scientists who could only hypothesize. Perhaps there are no good pollinators for cacao in Peru. The scientists also noted that only an average of 30 pollen grains were found on cacao flowers, much less than expected for successful pollination.&nbsp;



There is still much to investigate in the pollination of cacao. "Among other things, it would be important to identify the main pollinators," said Justine Vansynghel, lead researcher and PhD student.



This information could help improve the yields of cacao in native regions like Peru, which lags behind the pollination rates of plantations in Asia and Africa, probably because these plants are high yielding clones. More research may finally discover the pollinator but for now, cacao remains a delicious mystery.&nbsp;



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

Cacao tree pollination remains a mystery

It’s strange that cacao, the main ingredient in chocolate, is...

Empathy is by definition, trying to feel the experience of another. Researchers recently asked whether people empathize more with other people or with <a href="https://www.earth.com/news/experts-identify-100-cases-of-humans-passing-disease-to-animals/">animals</a>. The study was published in a special issue of the journal <a href="https://www.hogrefe.com/us/journal/social-psychology">Social Psychology</a>.



To investigate this question, scientists recruited 193 participants. The research subjects were then asked whether they wanted to empathize with a human or an animal. If the participants said human, they were shown a picture of a college age person and asked to put themselves in their situation. If they chose an animal, the participants were shown the image of a koala bear. In this study, the participants more often chose the human.&nbsp;



“Participants indicated that empathizing with animals felt more challenging, and that belief of empathy being more difficult drove them to choose animal empathy less," said study lead author Daryl Cameron of the <a href="https://rockethics.psu.edu/">Rock Ethics Institute</a>. "It’s possible that people felt empathizing with a mind that’s unlike our own was more challenging than imagining the experience of another human.”



Another study illuminated and complicated things a bit more. In a second study, two new groups of 192 and 197 participants were given two choices. First, researchers asked one group to either empathize with or just describe without empathizing a person. The second group was given the same choice but with a koala instead of a person. Interestingly, with the image of the human, people tended to avoid empathizing. With the image of the koala people didn’t avoid empathy but embraced it.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;



“It’s possible that if people are seeing humans and animals in competition, it might lead to them preferring to empathize with other humans,” said Cameron. “But if you don’t see that competition, and the situation is just deciding whether to empathize with an animal one day and a human the other, it seems that people don’t want to engage in human empathy but they're a little bit more interested in animals.”



The researchers hope that this sort of psychology study might help better target conservation efforts and in the end help further the cause of wild animals.&nbsp;



---



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

Do humans empathize more with people or other animals?

Empathy is by definition, trying to feel the experience of...

A new study led by the <a href="https://www.bas.ac.uk/">British Antarctic Survey</a> (BAS) has found that rising greenhouse gas emissions have a long-term warming effect on the Amundsen Sea in West Antarctica, leading to significant <a href="https://www.earth.com/news/how-antarctic-sea-ice-has-fluctuated-over-the-past-century/">sea ice</a> melting. Although scientific observations of this region only began in 1994, the patterns of ice loss the scientists mapped suggest that the ocean may have been gradually warming over the past century, due to a combination of natural and anthropogenic factors.



Ice loss from the West Antarctic Ice Sheet in the Amundsen Sea is one of the main contributors to sea level rises worldwide. According to the researchers, if this massive ice sheet were to melt completely, global sea levels could rise by up to three meters.



By using advanced computer modelling to simulate the response of the Southern Ocean to changes in the atmosphere from 1920 to 2013, the scientists found that the Amundsen Sea became increasingly warmer during this period, due to changes in wind patterns that increased temperatures by driving warm water currents towards and beneath the ice. These changes in wind patterns are partly driven by rising greenhouse emissions.



“The main cause of the warming in our simulations is changes in the winds near the edge of the Amundsen Sea that pump more warm water from the deep ocean onto the shallower continental shelf. These wind trends are partly caused by greenhouse gas emissions from the burning of fossil fuels,” the study authors explained.



According to study lead author Kaitlin Naughten, an ocean-ice modeler at BAS, if greenhouse gas emissions increase, further rises in ocean temperatures, ice melt, and global sea levels are to be expected. However, the fact that these patterns are partly caused by human activity should also give us reason to hope: if emissions are sufficiently reduced and wind patterns in the area are stabilized, this trend could be curbed and perhaps even reversed.



“Changes in the Southern Hemisphere westerly winds are a well-established climate response to the effect of greenhouse gases. However, the Amundsen Sea is also subject to very strong natural climate variability. The simulations suggest that both natural and anthropogenic changes are responsible for the ocean-driven ice loss from the West Antarctic Ice Sheet,” said study co-author Paul Holland, an oceanographer at BAS. While the natural changes occurring in the area are most probably beyond our control, urgent measures should be taken to curb emissions in order to protect our planet from catastrophic sea level rises.&nbsp;



The study is published in the journal <a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL094566">Geophysical Research 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

Sea ice loss is directly affected by greenhouse gas emissions

A new study led by the British Antarctic Survey (BAS)...

<a href="https://www.earth.com/news/as-oceans-warm-up-smaller-species-of-fish-will-dominate/">Oceans</a> are made up of multiple layers. Lighter, warmer waters sit at the top while denser, cooler waters can be found at the bottom. To move heat, ocean mixing is vital.&nbsp;



Ocean mixing also moves oxygen, nutrients and pollutants between different layers, playing a major role in how ecosystems sustain life. A new study has shown how fish can influence ocean ecosystems by circulating nutrients and oxygen around the waters when they spawn. Prior to this study, it was not previously understood how fish contribute to ocean mixing.



A team led by the <a href="https://www.southampton.ac.uk/">University of Southampton</a> spent fifteen days monitoring water turbulence in the Ría de Pontevedra, a bay in the northwest coast of the Iberian Peninsula. The experts measured variations in ocean current speed and temperature over very small distances.



It is known that turbulence and mixing increases during major storm events. The results of the study showed that increased levels of turbulence and mixing occurred every night, even without a storm.



The research team used acoustic data and samples collected with small fishing nets. This allowed the team to identify fish that were gathering in the area at night. The small nets were full of recently spawned eggs of European anchovy.&nbsp; The anchovies’ frantic behaviour during spawning had caused the turbulence. This is referred to as ‘biological mixing’.



“We believe that biological mixing was intense in our observations because the bay is highly stratified - the temperature and other properties vary significantly at different depths,” explained Dr. Bieito Fernández Castro, who led the study.&nbsp;



Previous studies suggested that biological turbulence causes minimal mixing because the circular motions fish generate while swimming are too small, especially in deeper ocean water. “However, we have shown that closer to land, where the layers change over a much shorter distance, the anchovies are able to mix them together,” said Dr. Castro.



While biological mixing may influence the open ocean, the study revealed that it can be significant in coastal ecosystems. This is because thriving marine life coexists with rapid changes in the make-up of the ocean.&nbsp;



The ocean mixing generated by fish could impact the redistribution of temperature, nutrients and oxygen, which play a fundamental role in the functioning of the ecosystem that fish rely on. The findings highlight the capacity of living organisms to influence the environment they live in.



“The observation of how our anchovies drove mixing was totally fortuitous. We were set to study how turbulence affects marine life and we end up showing, for the first time, that marine life can influence ocean turbulence, which in turn influences marine life!” concluded Dr Fernández Castro.



The research is published in the journal <a href="https://www.nature.com/ngeo/">Nature Geoscience</a>. To learn more, you can watch a short video of the study <a href="https://www.youtube.com/watch?v=f-fosxKyzQ8">here</a>.&nbsp;



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

Spawning fish generate ocean mixing, help sustain a healthy ecosystem

Oceans are made up of multiple layers. Lighter, warmer waters...

In arid Western states, the climate is becoming increasingly warmer and drier, leading to rises in the demand for water resources from humans and most ecosystems. According to a new study led by the <a href="https://www.dri.edu/">Desert Research Institute</a> (DRI), the atmosphere across most of the United States is also demanding a greater amount of water than it ⁰previously used to. These substantial increases in “atmospheric thirst” are leading causes of <a href="https://www.earth.com/news/flash-droughts-are-coming-on-faster-due-to-climate-change/">droughts</a>, wildfires, and reduced streamflows.



Evaporative demand – known colloquially as atmospheric thirst – is a measure of the loss of water from the earth’s surface to the atmosphere, calculated through variables such as temperature, humidity, wind speed, and solar radiation. By assessing trends in evaporative demand across the United States from 1980 to 2020, the researchers found massive increases in the Western states, particularly in the area centered around the Rio Grande and Lower Colorado rivers.



“This means that atmospheric thirst conditions in parts of the country are now verging outside of the range that was experienced 20 to 40 years ago, especially in some regions of the Southwest,” said lead author Christine Albano, an assistant professor of Ecohydrology at DRI. “This is really important to understand, because we know that atmospheric thirst is a persistent force in pushing Western landscapes and water supplies toward drought.”&nbsp;



Professor Albano and her colleagues have found that increases in temperature were responsible for 57 percent of the changes observed in these regions, while humidity, wind speed, and solar radiation played important yet lesser roles (26 percent, 10 percent, and 8 percent, respectively).



For farmers and other water users, increases in atmospheric thirst mean that more water will be required to meet existing needs.&nbsp;



“Our analysis suggests that crops now require more water than they did in the past and can be expected to require more water in the future,” said study co-author Justin Huntington, a research professor of Hydrology at DRI.&nbsp;



Other significant impacts of increased atmospheric thirst include droughts, rises in the frequency and extent of forest fires, and reduced streamflows.&nbsp;



“Our results indicate that, decade by decade, for every drop of precipitation that falls, less and less water is likely to drain into streams, wetlands, aquifers, or other water bodies,” said study co-author Michael Dettinger, a climate scientist at DRI. “Resource managers, policy makers, and the public need to be aware of these changes and plan for these impacts now and into the future.”



The study is published in the journal <a href="https://journals.ametsoc.org/view/journals/hydr/23/4/JHM-D-21-0163.1.xml">Hydrometeorology</a>.&nbsp;



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

Atmospheric thirst has increased in the US over the past decades

In arid Western states, the climate is becoming increasingly warmer...

An international team of researchers recently completed a study that confirmed a link between diet, habitat, and social behavior in weaver birds. This relationship is not a new idea; it was first hypothesized in 1964 by British ethologist, John Crook. Still, this is the first time a team has been able to support the hypothesis with statistical evidence.&nbsp;



Weaver birds are known for their elaborate nests. This family of songbirds are primarily found in sub-Saharan Africa. However, they live in various habitats. Some species live in the savannah, where they consume seeds. Other species live in the forest, and their preference is for insects.&nbsp;



After analyzing previous research, the scientists noticed several trends. They saw that birds on the savannah flocked together. Weavers living on the savannah also nested in colonies and were polygamous. However, birds living in the forest were solitary hunters, with no large nesting colonies, but monogamous pairing.&nbsp;



The study was led by Professor Tamás Székely from the <a href="https://www.bath.ac.uk/research-centres/milner-centre-for-evolution/">Milner Centre for Evolution</a> at the University of Bath. He explained why diet, habitat, and social behavior are affected by each other.



"For birds that feed on seeds in the open savannah, flocking together improves feeding efficiency because it makes it easier to locate patches where there are abundant seeds," said Professor Székely.



"Flocking also lowers the risk of predation out in the open by providing them safety in numbers."



"However, in open habitats such as the savannah there are limited nesting sites, meaning the birds live together in a colony and this often leads to polygamous breeding."



"On the other hand, forest-dwelling, insect-eating birds must search a wider area for food as insects are more widely distributed. The relatively safer, closed habitat of the forest provides lots of suitable nesting sites, so the birds don't need to live close together."



According to Professor Székely, this more solitary social system also means the birds are more likely to stick with the same mate during the breeding season."



Moreover, the researchers discovered details beyond Crook's hypothesis. They found that diet and habitat affect whether a species is dimorphic, meaning males and females have distinct differences in size or appearance. Polygamous species living on the savannah were more likely to be dimorphic, while forest-dwelling, monogamous species tend to have identical males and females.&nbsp;&nbsp;



The research team doesn't want to stop at weaver birds, and they look forward to testing Crook's theory on other bird species, mammals, fish, and insects.&nbsp;



The study is published in the journal <a href="https://www.journals.uchicago.edu/toc/an/current">The American Naturalist</a>.&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

Diets of weaver birds are influenced by their social lives

An international team of researchers recently completed a study that...

Rising numbers of free-roaming stray <a href="https://www.earth.com/news/how-to-tell-whether-you-cat-is-a-psychopath/">cats</a> is a global problem. They are considered one of the world’s most invasive species, posing a health risk to humans and destroying large numbers of wildlife. Nevertheless, people are reluctant to cull them, as they usually do with pests such as rats or cockroaches. A new study led by the <a href="https://en.huji.ac.il/en">Hebrew University of Jerusalem</a> (HUJI) has now investigated the impact of different protocols to control stray cat populations over a period of 12 years.



At the moment, the most popular and widespread population-control method is TNR - in which street cats are Trapped, Neutered, and Returned to the location where they were initially found.&nbsp;



“Although this method has been implemented in various parts of the world, there was controversial evidence regarding its effectiveness for reducing cat populations and no hard evidence regarding its effectiveness in reducing cat-related nuisances or improving their welfare,” said study lead author Eyal Klement, an expert in Veterinary Epidemiology at HUJI.



Professor Klement and his colleagues focused on one Israeli city (Rishon LeZion) where they tried out different population-control measures during three four-year periods. While in the first period there was no intervention, in the second one the scientists organized an intensive program of neutering cats in half of the city, using the other half as a control group. Finally, in the third period, neutering was applied city-wide.



Surprisingly, neutering cats in only half of the city did not seem to reduce cat populations at all. According to the researchers, the migration of unneutered cats into the area can explain this unexpected finding. While in the third case, a seven percent annual reduction of cat population was achieved, a rebound increase in the number of kittens was later on noted, most probably due to an increase in their survival rates due to lack of competition with the neutered, less aggressive cats.&nbsp;



“Intact cats are more territorial than their neutered counterparts.&nbsp;Once they move into a neighborhood with neutered cats, they tend to thrive and take over,” explained Professor Klement.&nbsp;&nbsp;&nbsp;



These results and further analysis suggest that, ideally, 70 percent of stray cat populations should be neutered on a continuous basis. Moreover, in order to avoid the rebound effect, cat food resources should be controlled in parallel to the TNR campaign.&nbsp;



“This can be achieved by setting up feeding stations in agreed-upon locations and by prohibiting feeding in other public areas,” said Professor Klement. Such a method would make sure that the cats are properly fed and the neutering procedures could be implemented efficiently, by catching the cats when they come to eat.



The study is published in the journal <a href="https://www.pnas.org/doi/full/10.1073/pnas.2119000119">Proceedings of the National Academy of Sciences</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

How can we control the growing issue of stray cats?

Rising numbers of free-roaming stray cats is a global problem....

In a new study from the <a href="https://www.leeds.ac.uk/">University of Leeds</a>, researchers have assessed more than 17,000 privately protected areas (PPAs) across five continents. The study is the largest of its kind to investigate how PPAs help conserve highly threatened regions and underrepresented <a href="https://www.earth.com/news/shrinking-habitats-alien-species-threaten-native-trout/">habitats</a>.



Privately protected areas are privately managed portions of land set aside to preserve biodiversity and ecosystems. While these regions are increasing in number, the extent of their contribution to conservation has remained unknown.



The experts found that, when compared to state protected areas, privately protected areas are twice as likely to be exposed to human disturbances, such as farming or mining. In addition, the study shows that PPAs are three times more likely to be in biomes with almost no established conservation reserves.



“Our study shows that privately protected areas can make unique and very real contributions to the conservation estate. They deserve more attention, recognition and resources for better design and implementation," said study lead author Rachel Palfrey.



“By recognizing their role in conservation efforts, more can be done to coordinate the establishment of privately protected areas and maximise their benefits."



“State governed protected areas dominate conservation strategies in most countries but government action alone will be insufficient to reach global conservation targets and help safeguard against devastating biodiversity loss."



The researchers found that PPAs account for 3.4 percent of land under protection, and increase the connectivity between conserved areas by more than seven percent. According to the researchers, connectivity is incredibly important in supporting seed dispersal and animal migration.&nbsp;



“The current global network of protected areas underrepresents key species and ecosystems. It lacks connectivity and does not adequately protect areas of high wildlife and biodiversity importance," said Dr. Johan Oldekop of the University of Manchester.&nbsp;



“Privately protected areas are not the silver bullet for conservation efforts, but they are clearly an important part of the picture."



“This study highlights the importance of using all available resources and interests to establish vitally important protected portions of land. Greater legislative, technical and financial support for privately protected areas could help facilitate their establishment and also strengthen legal frameworks for other forms of conservation, including indigenous reserves and community conserved areas.”



Dr. George Holmes noted that further research is needed to examine the underlying factors and governance structures that influence the landscape choices of privately protected areas.



“Future analyses should include efforts to better understand the role of different stakeholders, such as private landowners and land trusts, and their motivations for the establishment of privately protected areas, as well as assessments of national policies and incentives that support privately protected areas.”



Conservation efforts will be a key topic at the upcoming UN biodiversity Conference in May 2022.&nbsp;



The study is published in the journal <a href="https://www.nature.com/natecolevol/">Nature Ecology and Evolution</a>.



Image Credit: George Holmes, University of Leeds



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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

Private protected areas could help save threatened wildlife

In a new study from the University of Leeds, researchers...

Honey bees are pollinators of flowering <a href="https://www.earth.com/news/invisible-flower-colors-help-plants-survive/">plants</a> all over the world and are therefore critical for the production of food crops. In recent decades, honey bees have been subjected to numerous environmental and management stresses that have impacted their survival rates. Among these, the most devastating has been infection by the parasitic mite Varroa destructor.&nbsp;



Varroa is an external parasite of Asian and European honey bees. Not only does it attach to the bodies of adult and larval bees and suck out nutrients, but it also carries at least five viruses that are devastating to the bees. The parasite’s original host was Apis cerana, the Asian hive bee, but it was introduced to the European honey bee, Apis mellifera, in the mid-1800s. Since then it has spread to all continents and regions of the world, except Australia and Antarctica.&nbsp;



Interestingly, Asian honey bees show certain behavioral traits that help keep infestations of varroa mites under control. These behaviors include grooming mites off their own and other bees’ bodies, as well as getting rid of larvae that have been infected with mites. Such hygienic strategies have genetic components and are heritable. It is likely that, since the Asian honey bees have been exposed to varroa mite infestations over evolutionary time, natural selection has gradually favored the survival of colonies where bees practice these behaviors. As a result, Asian honey bees are largely resistant to the parasite.



In the U.S., scientists have spent 20 years breeding a line of European honey bees that also shows hygienic behavior towards infestations of varroa mites. Beekeepers in this country, as in many others, have resorted to using pesticides and other chemical agents to control varroa mites in bee colonies. This has meant that natural selection for more resistant bees has not been able to take place and apiculturists are faced with large losses in colony numbers each year.&nbsp;



In a new study, published today in the journal <a href="https://www.nature.com/srep/">Scientific Reports</a>, experts from the universities of Louisiana and Exeter, and from the Agricultural Research Service of the US Department of Agriculture (USDA), tested the survival rates of these varroa resistant “Pol-line” bees in the field. The study took across three US states (Mississippi, California, and North Dakota), where commercial beekeepers move tens of thousands of colonies annually to provide pollination services for large-scale agriculture. The survival of colonies of varroa resistant bees was compared with the survival of standard bees that had not been selectively bred for hygienic behavior.



“The&nbsp;Varroa&nbsp;mite is the greatest threat to managed honey bee colonies globally,” said&nbsp;<a href="https://biosciences.exeter.ac.uk/staff/profile/index.php?web_id=Thomas_OShea-Wheller">Dr. Thomas O’Shea-Wheller</a> of the&nbsp;<a href="https://www.exeter.ac.uk/research/esi/">Environment and Sustainability Institute</a>&nbsp;at Exeter's Penryn Campus in Cornwall.



“So far, new methods to control the mites – and the diseases that they carry – have had limited success, and the mites are becoming increasingly resistant to chemical treatments. It’s a ticking time-bomb.”&nbsp;



The results of the study showed that the mite-resistant bee colonies were more than twice as likely to survive the winter (60% survival compared to 26% in standard honey bee colonies). The standard honey bees experienced high losses unless extensive chemical treatments were used. Colony survival over the winter is particularly important for beekeepers, because honey bees are needed in early spring to pollinate many valuable crops.&nbsp;



“By selectively breeding bees that identify and remove mites from their colonies, our study found a significant reduction in mite numbers, and crucially, a two-fold increase in colony survival,” explained Dr. O’Shea-Wheller. “While this is the first large-scale trial, continued breeding and use of these bees has shown consistently promising results.”



Although European honey bees are not naturally resistant to varroa mite infestations, they do show some of the specific hygienic behaviors that are common in Asian honey bees. The incidence of the cleaning behaviors is very low but it does indicate that the genes for these behaviors are present. By selectively breeding for these behavioral traits, colonies can been produced that automatically protect themselves from infestation, while maintaining large colony sizes and ample honey production.



“The great thing about this particular trait is that we’ve learned honey bees of all types express it at some level, so we know that with the right tools, it can be promoted and selected for in everyone’s bees,” said research molecular biologist Dr. Michael Simone-Finstrom, of the USDA Agricultural Research Service.



According to Dr. O’Shea-Wheller: “This kind of resistance provides a natural and sustainable solution to the threat posed by&nbsp;Varroa&nbsp;mites, and does not rely on chemicals or human intervention.”



The current study also monitored the levels of three debilitating viruses present in the varroa resistant colonies. These viruses (DWV-A, DWV-B and CVPV) are carried by the mites and transmitted to the bees. The results showed that the colonies bred for varroa resistant behavior also had significantly lower levels of these viruses. This is explained by the fact that cleaning behavior by the bees removes mites from the colonies and therefore also removes the viruses.&nbsp;&nbsp;



Interestingly however, when examined separately from levels of mite infestation, these viruses were not strong predictors of colony losses.



“A lot of research is focused on the viruses, with perhaps not enough focus on the mites themselves,” said Dr. O’Shea-Wheller.



“The viruses are clearly important, but we need to take a step back and be rigorous in delivering the best practical outcomes, because if you control the mites, you automatically control for the viruses that they transmit.”



Dr. O’Shea-Wheller said that breeding and testing is expensive and takes time, but that breeding mite-resistant bees is cost-effective in the long term, and is likely to be the only sustainable solution to deal with the&nbsp;Varroa&nbsp;pandemic.



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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

Breeding “cleaner” bees may stop varroa mites in their tracks

Honey bees are pollinators of flowering plants all over the...

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https://www.youtube.com/watch?v=3Y4eLFNYrKE
</div></figure>



On the unforgiving landscape of North Greenland, temperatures drop and sunlight barely penetrates through the polar winter. It was here, however, that an international team of scientists found <a href="https://www.earth.com/news/predatory-worms-were-terror-beasts-half-a-billion-years-ago/#google_vignette" target="_blank" rel="noreferrer noopener">evidence of sea monsters</a> that would change our understanding of ocean life in the past.



This video captures the discovery of Timorebestia fossils that had been hidden for more than 500 million years in the Sirius Passet formation. The "terror beasts," as they are called, are a hidden chapter in the evolutionary history of <a href="https://www.earth.com" target="_blank" rel="noreferrer noopener">Earth</a>, showing that sophisticated predator-prey interactions occurred much earlier than previously envisioned.



Dr. Jakob Vinther and his research team at the <a href="https://www.bristol.ac.uk/" target="_blank" rel="noreferrer noopener">University of Bristol</a>, in collaboration with researchers at the <a href="https://eng.kopri.re.kr/" target="_blank" rel="noreferrer noopener">Korean Polar Research Institute</a>, braved extreme weather conditions at 82.5 north latitude to locate these giant creatures. Using sophisticated electron microprobe analysis, they revealed the detailed anatomy of the animals, including their muscle and nerve tissues.



The find upsets the traditional timeline of sea predators. Although we've long appreciated that Cambrian oceans were at one time ruled by <a href="https://www.youtube.com/watch?v=jWI3-UgA3_o&amp;list=PL1QLQMW9MWDwpkFOnvgAmu7wT6rZmYqdJ&amp;index=19" target="_blank" rel="noreferrer noopener">arthropods</a>, these discoveries indicate that relatives of arrow worms were first to dominate the seas. These worms were building sophisticated food webs several million years before other predator groups arose.



Each fossil is a story of ancient hunger, with fossil stomach contents revealing these meter-long beasts dined on heavily armored arthropods regularly, cementing their place as the ocean's first apex predators.



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Worms dominated seas before dinosaurs

https://www.youtube.com/watch?v=3Y4eLFNYrKE On the unforgiving landscape of North Greenland, temperatures drop...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=Ow3JH03PqEQ
</div><figcaption class="wp-element-caption">New York is the site of the world's oldest forest.</figcaption></figure>



<h2 class="wp-block-heading" id="h-385-million-year-old-trees-discovered">385-million-year-old trees discovered</h2>



Scientists have uncovered something extraordinary just two hours north of New York City. The <a href="https://www.earth.com/news/worlds-oldest-forest-discovered-close-to-new-york-city/" target="_blank" rel="noreferrer noopener">world's oldest forest</a>, dating back 385 million years, offers a window into how Earth's first complex forests shaped our planet's atmosphere.



Located near <a href="https://townofcairo.com/" target="_blank" rel="noreferrer noopener">Cairo, New York</a>, in Greene County, these weren't merely primitive plants struggling to survive. These were sophisticated trees with root systems remarkably similar to modern forests. This ancient woodland predates dinosaurs by 140 million years.



<h2 class="wp-block-heading" id="h-the-cairo-forest-discovery">The Cairo forest discovery</h2>



385 million years ago, upstate New York was a tropical paradise near the equator. Thanks to continental drift, this ancient forest has traveled thousands of miles to its current location.



The fossil forest sits in an abandoned quarry, roughly half the size of a football field. This represents just a slice of what was likely a massive forest system stretching from New York into Pennsylvania.



Charles Ver Straeten, curator of sedimentary rocks at the <a href="https://www.nysm.nysed.gov/" target="_blank" rel="noreferrer noopener">New York State Museum</a>, made the discovery in 2009. While scouting the former highway department property, his trained eye spotted wandering patterns in the stone that looked like marine features.



<h2 class="wp-block-heading" id="h-revolutionary-age-and-preservation">Revolutionary age and preservation</h2>



The site contains 385-million-year-old rocks with fossilized woody roots forming horizontal patterns up to 18 feet (5.5 meters) wide. As Christopher Berry, a paleobotanist at Cardiff University, explains: "You are walking through the roots of ancient trees."



This discovery pushes back advanced tree evolution by millions of years. The research, published in <a href="https://www.cell.com/current-biology/home" target="_blank" rel="noreferrer noopener">Current Biology</a> in December 2019, fundamentally changes our understanding of when complex forests first emerged.



Researchers believe a massive flood buried the forest floor, creating perfect fossilization conditions. Over millions of years, sediment hardened into rock, preserving these root patterns like nature's time capsule.



<h2 class="wp-block-heading" id="h-meet-archaeopteris-the-first-modern-tree">Meet Archaeopteris: the first modern tree</h2>



The star of this ancient forest is Archaeopteris – not to be confused with the feathered dinosaur Archaeopteryx. This tree was far older and more revolutionary.



William Stein from <a href="https://www.binghamton.edu/" target="_blank" rel="noreferrer noopener">Binghamton University</a> describes the roots as "strikingly modern, essentially what you'd see outside in my yard right now." These weren't simple root systems you'd expect from ancient plants.



Some fossilized roots are six inches (15 centimeters) in diameter, forming 36-foot-wide (11-meter) patterns. These giants grew up to 65 feet (20 meters) tall with five-foot-diameter (1.5-meter) trunks.



<h2 class="wp-block-heading" id="h-climate-changing-impact">Climate-changing impact</h2>



These trees fundamentally changed Earth's environment. Kevin Boyce, a Stanford University geoscientist, explains how their deep roots triggered "weathering," chemical reactions that pulled carbon dioxide from the atmosphere.



This process dropped atmospheric CO2 levels from 10-15 times higher than today to roughly modern concentrations. These ancient trees helped create atmospheric conditions that made complex life possible.



<h2 class="wp-block-heading" id="h-ancient-forest-ecosystem">Ancient forest ecosystem</h2>



The forest was remarkably diverse. Scientists identified Eospermatopteris, palm tree-like plants with short roots that reached 30 feet (9 meters) tall but lacked woody structure. The forest also housed cladoxylopsids and a mysterious third species still being studied.



All reproduced through spores rather than seeds – millions of years before seeds evolved. This tropical environment had no grass, flowers, or flying insects, just towering trees creating Earth's first complex forest canopy.



<h2 class="wp-block-heading" id="h-scientific-significance">Scientific significance</h2>



Before this finding, the Gilboa forest, located 25 miles (40 kilometers) away, held the "oldest forest" title. Cairo's trees are 2-3 million years older, showing that complex forest ecosystems developed much faster than scientists believed possible.



Patricia Gensel, a <a href="https://www.unc.edu/" target="_blank" rel="noreferrer noopener">University of North Carolina</a> paleobotanist, notes: "The size of those root systems is really changing the picture. Even 20 years ago, researchers assumed trees with such complex root systems didn't evolve so early."



The Cairo site presents three unique root systems, suggesting Devonian period forests were diverse ecosystems with different trees occupying different environmental niches, much like today's forests.



<h2 class="wp-block-heading" id="h-modern-preservation-efforts">Modern preservation efforts</h2>



In 2022, New York State Senator Michelle Hinchey secured a $170,000 grant for the town of Cairo to construct specialized fencing around the fossil forest site. The town plans to conduct a feasibility study exploring the possibility of creating an educational center and working lab on-site.



Joe Hasenkopf, chair of the Cairo Planning Board, hopes to partner with educational institutions to create a research facility serving scientists, students, and the public.



<h2 class="wp-block-heading" id="h-lessons-for-today-s-climate">Lessons for today's climate</h2>



Why does a 385-million-year-old forest matter today? It shows how dramatically forests can change Earth's climate. These ancient woodlands created the atmospheric conditions supporting complex life.



Understanding how prehistoric forests transformed the planet helps us appreciate modern forests' critical role in addressing climate change. Forests remain Earth's most effective carbon capture systems.



These prehistoric trees changed Earth's atmosphere by pulling massive amounts of carbon dioxide from the air. As we face modern climate challenges, this ancient forest reminds us of trees' incredible power to transform our planet's environment.



The next time you walk through a forest, remember you're experiencing an ecosystem whose blueprint was established 385 million years ago in upstate New York. These ancient pioneers didn't just survive – they thrived and changed the world forever.



The full study was published in the journal Current Biology.



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Earth's oldest forest found in the United States

https://www.youtube.com/watch?v=Ow3JH03PqEQ New York is the site of the world's oldest...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=prrq8Ql81zk
</div><figcaption class="wp-element-caption">Acid rain and a crisis solved.</figcaption></figure>



<h2 class="wp-block-heading" id="h-why-don-t-we-ever-hear-about-acid-rain-anymore-the-environmental-crisis-that-was-solved">Why don't we ever hear about "acid rain" anymore? The environmental crisis that was solved</h2>



Remember the 1980s when acid rain dominated headlines? Dire warnings about rain eating buildings, killing fish, and destroying forests filled every news cycle. Then, almost like magic, acid rain vanished from public discourse. What happened? Did we actually solve one of the late 20th century's most pressing environmental challenges?



The answer might surprise you. Unlike many environmental issues that drag on indefinitely, acid rain represents one of modern history's most successful ecological recovery stories. It's a tale of science, politics, and technology working together to tackle what seemed impossible.



<h2 class="wp-block-heading">What was acid rain?</h2>



Acid rain isn't regular rain having a bad day – it's precipitation that became significantly more acidic due to air pollution. When power plants, factories, and vehicles burn fossil fuels, they release sulfur dioxide (SO2) and nitrogen oxides (NOx) into the atmosphere.



<h2 class="wp-block-heading">The science behind it</h2>



Think of acid rain as nature's chemistry experiment gone wrong. These compounds react with water, oxygen, and other chemicals to form sulfuric and nitric acids. When mixed with water vapor in clouds, they create precipitation with dangerously low pH levels.



While clean rain has a pH of about 5.6, acid rain could drop as low as 4.2 to 4.4 – roughly as acidic as tomato juice or coffee. According to US Geological Survey documentation, Scottish chemist Angus Smith first coined "acid rain" in 1872, but it didn't become a household phrase until the 1960s and 1970s when Swedish scientist Svante Odén documented its devastating effects on Scandinavian lakes and European forests.



<h2 class="wp-block-heading">The crisis at its peak</h2>



During the height of public concern, environmental damage was both widespread and visible. This wasn't some abstract future threat – people could see destruction happening in real-time.



<h2 class="wp-block-heading">Environmental devastation</h2>



The most dramatic impacts were impossible to ignore. Research documented by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation shows that in the Adirondack Mountains, more than 200 lakes became so acidic they couldn't support fish life. The Adirondack Council reports that 409 lakes once supported brook trout, but many lost their fish populations due to acid rain.



By 1976, when scientists cataloged all acidified lakes in the Adirondack Park, researchers found that half of the lakes over 2,000 feet above sea level had no fish, according to studies published in environmental journals. The acidification process worked like a slow-motion disaster. As acid rain fell into watersheds, it gradually lowered pH levels. Fish couldn't survive in acidic water, and their food sources died off too.



Trees at high elevations showed stress directly linked to acid rain. It weakened them by leaching nutrients and making them susceptible to disease. Historical records show Germany's Black Forest saw nearly half its trees damaged by the mid-1980s.



<h2 class="wp-block-heading">Economic impact</h2>



Acid rain wasn't just environmental – it was expensive. Acidic precipitation corroded infrastructure, buildings, and monuments. Historic stone structures deteriorated at accelerated rates. Tourism suffered as lakes became fishless and forests declined. EPA economic analyses from the period documented repair costs mounting into billions annually.



<h2 class="wp-block-heading">The solution: government action and technology</h2>



Transformation from crisis to success required unprecedented cooperation between governments, industries, and environmental groups.



<h2 class="wp-block-heading">The Clean Air Act of 1990</h2>



The turning point came with the Clean Air Act Amendments of 1990, signed by President George H.W. Bush. This represented a fundamentally new approach to environmental regulation, as documented in EPA historical records.



<h2 class="wp-block-heading">Cap-and-trade success</h2>



Instead of mandating specific technologies, the 1990 amendments introduced something revolutionary: a cap-and-trade system for sulfur dioxide emissions. EPA program documentation shows this market-based approach set overall limits but allowed companies to trade emission allowances.



The genius was harnessing market forces to find cost-effective pollution reduction. Companies reducing emissions cheaply could sell excess allowances to those facing higher costs. Research published in environmental economics journals and EPA progress reports shows this resulted in dramatic SO2 reduction at a fraction of projected costs.



<h2 class="wp-block-heading">Technology advances</h2>



Policy provided the framework, but technology made reductions possible. Studies in atmospheric science journals document the widespread adoption of flue gas desulfurization systems ("scrubbers") that removed sulfur dioxide before it reached the atmosphere. By the 2000s, new installations could remove over 95% of SO2 emissions, according to EPA technical reports.



The push coincided with cleaner energy development. Natural gas produces fewer sulfur compounds than coal. Wind and solar, emerging in the 1990s, captured growing market share, reducing reliance on high-sulfur coal.



<h2 class="wp-block-heading" id="h-why-we-don-t-hear-about-it-today">Why we don't hear about it today</h2>



Why did acid rain disappear from headlines? Simple: the problem was largely solved.



<h2 class="wp-block-heading">Success doesn't make news</h2>



There's an old journalism saying: "If it bleeds, it leads." Environmental success stories don't generate urgency like crisis reporting. Media attention shifted to other challenges: climate change, plastic pollution, and biodiversity loss. There's only so much environmental anxiety the public can absorb, and newer concerns replaced acid rain.



<h2 class="wp-block-heading">Mission accomplished</h2>



The primary reason is beautifully simple: interventions worked. EPA monitoring data shows sulfur dioxide emissions dropped over 90% since 1990. Academic research published in environmental science journals confirms pH levels in formerly affected areas returned closer to normal. This represents one of history's most dramatic environmental recoveries. Studies by the Adirondack Lakes Survey Corporation show fishless lakes now support healthy populations. Forests recovered, and building damage slowed dramatically.



<h2 class="wp-block-heading" id="h-is-it-really-gone">Is it really gone?</h2>



The crisis is largely resolved, but monitoring data shows the problem isn't completely eliminated – it's managed to acceptable levels. Some areas still experience occasional events during high pollution periods. International environmental research indicates that rapidly industrializing Asian countries face similar problems to what we experienced decades ago, though they're implementing successful strategies.



EPA research shows nitrogen oxide emissions proved more challenging than sulfur dioxide, coming from vehicles and mobile sources. Climate science studies suggest changing weather patterns add complexity to how acid rain forms and falls.



<h2 class="wp-block-heading">What this teaches us</h2>



The acid rain experience proves that seemingly intractable environmental problems can be solved with scientific understanding, political will, and technological innovation. Environmental monitoring data shows recovery speed was remarkable – within a decade, measurable improvements appeared in air quality and ecosystem health.



Success came from bipartisan support across party lines. Policy analysis studies show the market-based approach appealed to those preferring economic incentives while achieving environmental goals. This support created lasting policy surviving political changes.



<h2 class="wp-block-heading">Conclusion</h2>



Acid rain's disappearance from public consciousness represents environmental science's greatest success stories. Through effective regulation, technological innovation, and international cooperation, we transformed an overwhelming crisis into a manageable challenge.



Today's silence isn't because we forgot – it's because we solved it. The 1990 Clean Air Act, combined with technology and energy market changes, reduced acid rain emissions over 90%, according to comprehensive EPA data analysis.



This success offers hope for current challenges. It proves complex problems can be solved when science, policy, and technology work together. As we face climate change and plastic pollution, acid rain reminds us that dramatic positive change is possible.



Next time someone asks whether environmental regulations work, remember acid rain. It's proof that sometimes, we get it right.



<hr class="wp-block-separator has-alpha-channel-opacity"/>



Sources: This article draws from EPA official documentation and progress reports, peer-reviewed research published in environmental and atmospheric science journals, historical data from the Adirondack Lakes Survey Corporation, New York State Department of Environmental Conservation records, US Geological Survey publications, policy analysis studies, and environmental monitoring data collected over three decades.



<h2 class="wp-block-heading">Frequently Asked Questions</h2>



1. Is acid rain completely gone? No, but EPA monitoring shows it's reduced to manageable levels. US sulfur dioxide emissions dropped over 90% since 1990, making acid rain much less severe than the 1980s crisis.



2. How long did solving take? Environmental monitoring data shows significant improvements began within 5-10 years of 1990s emission controls. Full ecosystem recovery took longer – some areas need 20-30 years for complete recovery.



3. What made the solution successful? Clear scientific understanding, visible damage motivating action, bipartisan support, available technology, and innovative market-based policies like cap-and-trade.



4. Do other countries have acid rain problems? Yes, particularly rapidly industrializing Asian countries. However, international environmental research shows many implement similar successful control strategies.



5. Could acid rain return? Potentially, if regulations weaken or we return to high-sulfur coal without controls, though effects would take years to become severe according to environmental projections.



6. Can you recommend any teaching tools on the subject of "acid rain"? The United States Environmental Protection Agency produced a wonderful teacher's guide for ages 14 and under that you can find on the EPA website here: <a href="https://www.epa.gov/sites/default/files/2017-03/documents/teachersguide.pdf" target="_blank" rel="noreferrer noopener">https://www.epa.gov/sites/default/files/2017-03/documents/teachersguide.pdf</a>



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The environmental problem we actually solved

https://www.youtube.com/watch?v=prrq8Ql81zk Acid rain and a crisis solved. Why don't we...

Fresh,Radish,Harvest,On,Soil,In,Garden.

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Mid-July is an opportune time to kick-start a thriving fall garden, and this guide lays out the best vegetables and herbs to plant now for a fruitful autumn harvest. 



Fast-growing leafy greens such as spinach, lettuce, kale, and arugula perform especially well in the waning summer heat, with harvests beginning as soon as 30 days. 



These cool-season crops relish the transition into fall, offering repeated yields with cut-and-come-again methods.



Root vegetables like radishes, carrots, and beets also excel during this period. Radishes deliver satisfaction in under a month, while carrots and beets mature in about two months. Employing succession planting ensures a continuous stream of produce deep into the cooler months. 



For a boost of fresh flavor, herbs like cilantro, basil, dill, and chervil are excellent picks. These heat-loving varieties flourish in July’s warmth and are harvest-ready in about 30 days, especially when sown continuously.



Gardeners in zones 6 through 9 can benefit from planting bush beans and snap peas, which don’t require trellising and are ideal for compact plots. 



Maturing in 50–60 days, they’re a smart choice for quick, protein-rich harvests. For those in hotter regions, heat-tolerant crops such as okra and southern peas provide reliable yields and thrive in scorching conditions.



This guide emphasizes more than crop selection—it highlights the importance of timing, soil preparation, and ongoing sowing techniques. 



With thoughtful planning and attention to regional climate needs, even late-summer gardeners can enjoy fresh salads, hearty stews, and the satisfaction of a robust, homegrown harvest well into fall.



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What to plant in your garden in mid-July

https://youtu.be/Fi2OeEwuzRM?si=vTyd2m9FMmtyWkex Mid-July is an opportune time to kick-start a thriving...

Green,Ecoduct,Over,An,Empty,Highway,During,Sunset.

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A new long-term study in Monkton, Vermont, reveals that wildlife tunnels significantly reduce amphibian road mortality during seasonal migrations. 



Frogs and salamanders often cross roads to reach breeding ponds each spring, but many are killed by vehicles. 



Researchers from the <a href="https://www.uvm.edu/" target="_blank" rel="noreferrer noopener">University of Vermont</a>, in collaboration with local citizens and the Vermont Agency of Natural Resources, installed two underpass tunnels in 2015. 



Over a 12-year monitoring period, they observed an 80.2% reduction in amphibian deaths, and up to 94% for non-climbing species like salamanders. 



The study used a before-after-control-impact design and documented more than 5,200 amphibians, highlighting the tunnels’ effectiveness even in nearby buffer zones.



Funded at $342,397 - far cheaper than wildlife crossings for large mammals - the project showcased the power of community-led conservation.



Local groups initiated the effort after observing mass amphibian deaths. Wildlife cameras later captured over 2,200 amphibians using a tunnel in just one spring, along with other species like raccoons and bobcats, indicating wider ecosystem benefits.



This marks the first peer-reviewed, long-term data set in the northeastern U.S. confirming amphibian-specific underpasses work. 



The study urges transportation departments to incorporate these designs into road planning and highlights how community action, thoughtful infrastructure, and persistence can make a real difference for biodiversity.



The full study was published in the <a href="https://linkinghub.elsevier.com/retrieve/pii/S1617138125000780" target="_blank" rel="noreferrer noopener">Journal for Nature Conservation</a>.



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Wildlife tunnels save millions of amphibians

https://youtu.be/XYgiPzmNBTU?si=eFYY7gPHU1JznLvU A new long-term study in Monkton, Vermont, reveals that...

Scientists are transforming chocolate into a functional food by infusing it with probiotics and prebiotics, aiming to create a treat that satisfies cravings while supporting gut health. 



The challenge lies in maintaining chocolate's beloved texture and flavor while adding health benefits.



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https://youtu.be/Ug657J67iEo?si=w96YjGMsg939LD_3
</div></figure>



Probiotics - beneficial microbes that balance gut bacteria and aid digestion - are typically fragile and can be destroyed by stomach acid or processing. 



Prebiotics act as food for these microbes, helping them thrive. Together, they form "synbiotics," a powerful health combination.



Researchers Smriti Gaur and Shubhi Singh from India's Jaypee Institute of Information Technology took an innovative approach, using natural prebiotics like corn and honey instead of complex processing methods. 



They created five chocolate varieties: a control and four synbiotic versions containing different combinations of prebiotics, probiotics (Lactobacillus strains), and flavor enhancers (cinnamon or orange).



Laboratory simulations of human digestion showed the probiotics remained viable for over five hours, suggesting they could survive long enough to benefit gut health.



Taste tests were positive, with researchers particularly enjoying the orange-flavored variety, describing it as having "vibrant citrus notes" complementing the "rich cocoa" with a "luxurious" texture.



This research represents just the beginning. With further refinement of strains, textures, and flavors, chocolate could evolve beyond mere indulgence to become a functional food that nourishes while it delights.



The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsfoodscitech.4c00741" target="_blank" rel="noreferrer noopener">ACS Food Science &amp; Technology</a>.

Is chocolate the next nutritional powerhouse?

Scientists are transforming chocolate into a functional food by infusing...

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

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

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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

Detecting mercury contamination with the tap of a finger

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

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



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



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



Video Credit: ACS Reactions



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



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

How does salt makes things taste better?

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

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



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



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



Video/ Image Credit: ESA



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



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

Santiago, Chile in South America

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

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

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



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



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



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



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



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



Video Credit: Johns Hopkins&nbsp;



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



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

Interactive map of the universe includes 200,000 galaxies

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

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



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



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



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



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



Video Credit: ESA&nbsp;&nbsp;



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



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

Lesotho: Africa's "Kingdom in the Sky"

[sendtonews key="uV9Lh2fQbV-1760058-12187" type="single"] Lesotho: Africa's "Kingdom in the Sky" Today’s...

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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

[sendtonews key="qjvhBOBnY8-2426650-12187" 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 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

[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

[sendtonews key="6HyfrAJTBI-1831843-12187" type="single"] Today’s Video of the Day from the...

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"

[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...

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