It's no secret that the global health community has been grappling with the catastrophic impacts of the COVID-19 pandemic since it arose in 2019. This disease has presented unprecedented challenges in treatment and prevention, and we still do not fully understand the behavior of the SARS-CoV-2 virus.



As of today, the World Health Organization has documented over 770 million COVID-19 cases worldwide, indicating the extensive reach and impact that this virus has had on global populations.



<h2 class="wp-block-heading" id="h-the-mystery-of-how-covid-19-travels">The mystery of how COVID-19 travels</h2>



While we have decent knowledge about how the <a href="https://www.earth.com/news/covid-19-virus-lingers-body-two-years-after-infection/" target="_blank" rel="noreferrer noopener">virus</a> enters our bodies - by attaching onto healthy cells in our nose and throat - there remains a level of mystery about how COVID-19 further travels and spreads once inside an airway, and how it contributes to severe illness and long-term complications.



But recently, thanks to extensive research efforts and collaborative studies, a new piece of the puzzle has been identified. The findings offer fresh insights that may inform future treatment strategies and preventive measures.



Scientists at <a href="https://www.nm.org/" target="_blank" rel="noreferrer noopener">Northwestern Medicine</a> embarked on a mission to uncover the mysteries of SARS-CoV-2 's proliferation in our bodies.



One of their most significant findings was that the virus uses our body's own mucus as its personal highway into the lower lungs.



<h2 class="wp-block-heading" id="h-mucus-the-unexpected-accomplice">Mucus: The unexpected accomplice</h2>



In their study, which was published recently in Nature Communications, the researchers performed live imaging on human bronchial epithelium cells after they were exposed to SARS-CoV-2 virus.



Their observations revealed the virus' cunning tactic - the movement of our own mucus helps the virus to travel inside the respiratory tract.



This eventually leads to the formation of <a href="https://www.earth.com/news/how-covid-19-is-transmitted-through-aerosols/" target="_blank" rel="noreferrer noopener">infectious aerosols</a>, which can further affect other individuals.



"The virus goes where the mucus goes," said Mark Becker, the leading student author of the study.



We generally understand mucus as a protective shield against infection, that traps viruses and other harmful particles before they can enter the tissues. Our own ciliated cells help to "sweep" dirty mucus upwards towards the throat, thus keeping the respiratory surfaces clean.



Ironically, when exploited by the SARS-CoV-2 virus , this protective defense becomes an accomplice that aids the spread after <a href="https://www.earth.com/news/covid-impacts-the-brain-through-inflammation-not-infection/" target="_blank" rel="noreferrer noopener">infection</a>.



<h2 class="wp-block-heading" id="h-covid-19-insights-and-future-research">COVID-19 insights and future research</h2>



While funding for COVID-19 related research has started to decrease, the experts remain hopeful. 



They believe their discovery of how COVID-19 travels could have substantial applications in the context of other viral diseases as well, specifically <a href="https://www.earth.com/news/genetic-variant-linked-to-both-covid-risk-and-hiv-protection/" target="_blank" rel="noreferrer noopener">HIV</a>.



"The mucosal environment most similar to the lungs is the upper female reproductive tract," noted study senior author Dr. Thomas Hope.



Perhaps, then, this understanding of how the virus that causes COVID-19 manoeuvres through the respiratory tract can open doors to new research on other diseases that may similarly exploit the supply of mucus.



<h2 class="wp-block-heading" id="h-a-story-of-scientific-innovation">A story of scientific innovation </h2>



The success of this study is also a reflection of the robust infrastructure and commitment at Northwestern Medicine.



"The university really supported us and that is a testament to what a great environment Northwestern Medicine is," noted Dr. Hope.



It's a story of scientific innovation, pushing the boundaries of our understanding of the virus that has turned our world upside down. And above all, it's about teamwork - because that's how scientific breakthroughs happen.



This research contributes to the ever-growing body of knowledge about COVID-19. It demonstrates the virus's surprisingly strategic use of our <a href="https://www.earth.com/news/reprogramming-the-immune-system-to-attack-cancer-cells/" target="_blank" rel="noreferrer noopener">body's own defenses</a>.



<h2 class="wp-block-heading" id="h-covid-19-insights-and-innovative-treatments">COVID-19 insights and innovative treatments</h2>



The newfound understanding of SARS-CoV-2's behavior in the mucosal environment has sparked interest in developing innovative treatment approaches.



Researchers are now looking at how this knowledge could be applied to create therapies that reinforce mucosal barriers, potentially preventing viral entry and spread. 



This type of preventive treatment could revolutionize how viral diseases are managed, particularly for infections that target mucosal tissues.



By focusing on fortifying the body’s first line of defense, scientists hope to reduce the severity and transmission of certain viral diseases.



Beyond COVID-19, these strategies could offer hope for combating other viruses that similarly exploit mucosal pathways, such as influenza and respiratory syncytial virus (RSV). 



The potential for cross-applicability means that advancements made now could lay the groundwork for a more resilient response to future viral outbreaks, and create a broad-spectrum approach to viral prevention and treatment.



The study is published in the journal <a href="https://www.nature.com/articles/s41467-024-53791-4" target="_blank" rel="noreferrer noopener">Nature Communications</a>.



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How the COVID-19 virus travels deep inside our lungs

It's no secret that the global health community has been grappling with the catastrophic impacts of the COVID-19 pandemic since it arose in 2019. This disease has presented unprecedented challenges in treatment and prevention, and we still do not fully understand the behavior of the SARS-CoV-2 virus. As of today, the World Health Organization has documented over 770 million COVID-19 cases worldwide, indicating the extensive reach and impact that this virus has had on global populations. The mystery of how COVID-19 travels While we have decent knowledge...

Plants let their <a href="https://www.earth.com/news/invisible-colors-in-sunflowers-dont-only-attract-bees/">flowers</a> fade quickly for protection from detrimental microbes, according to a study led by experts at <a href="https://www.kyoto-u.ac.jp/en">Kyoto University</a>. Using field experiments and plant microbiome analyses, the researchers discovered that microbes growing on flowers can have a negative impact on fruit yields. As a defense mechanism, plants are quick to shed their flowers before the microbes increase in abundance.



"The results suggest that old flowers harbor microbial communities different from those at anthesis, and that the microbes abundant on old flowers negatively affect plant reproduction," wrote the study authors.&nbsp;



"Although it has received little attention, antagonistic microbes that rapidly proliferate on the flowers may have affected the evolution of various flower characteristics such as flower volatiles and life span."



Previously, researchers have investigated the tradeoff between energy that plants spend on producing and maintaining their flowers. Since flowers serve as a reproductive structure, it seems that plants would benefit from keeping them longer.&nbsp;



In an earlier study, the Kyoto team had looked at the mystery of why plants invest their energy to produce fragile flowers that wither quickly, rather than investing a bit more energy to produce flowers that are more durable.



“Interestingly, flower lifespan is negatively correlated with temperature; the hotter the environment where they bloom, the shorter the period a plant retains them. The phenomenon has been known for a long time,” said study co-author Shoko Sakai.



“Then, at some point, I came up with the hypothesis that antagonistic microbes, such as bacteria and fungi growing on flowers after the flower bud opens, must be the driver that shortens the lifespan of a flower. I doubted that it was a coincidence that microbes grow faster in higher temperatures.”



The team conducted field experiments to determine what microbial communities appear on flowers that live longer. The experts transferred microbes from old flowers of wild ginger to other wild ginger plants with new flowers that had just opened.



The experimental plants ultimately produced fewer fruits, despite the fact that there were no visible signs of infection or disease. When the researchers analyzed the microbiomes of the plants, they found several groups of bacteria that were increasing with time.&nbsp;



“So far, flower characteristics have mostly been studied in the context of their interactions with pollinators," said Sakai. "Recent studies have raised the question whether we have overlooked the roles of microbes in the studies of floral characteristics. For example, flower volatiles - which are often regarded as a primary pollinator attractant - can also function to suppress antagonistic microbes."



"The impacts of microbes on plant reproductive ecology may be more deeply embedded in the evolution of angiosperms than we have considered."



The study is published in the journal <a href="https://mbmg.pensoft.net/">Metabarcoding and Metagenomics</a>.



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

Plants shed their flowers quickly for protection

Plants let their flowers fade quickly for protection from detrimental...

Each year, the United States spends almost a trillion dollars attempting to combat metallic corrosion, an electrochemical reaction which occurs when metals oxidize and begin to rust. Now, a team of researchers led by the <a href="https://www.osu.edu/">Ohio State University</a> (OSU) has estimated how much corrosion is gradually worsening global carbon <a href="https://www.earth.com/news/plant-roots-will-increase-arctic-co2-emissions-by-40-billion-tons/">emissions</a>.&nbsp;



Although previous research has already estimated the economic cost of corrosion to be about three to four percent of United States’ gross domestic product, this is the first study to quantify the environmental impact associated with steel corrosion.



Global steel production has increased steadily for decades and, since steel has poor resistance to corrosion, part of that demand is to replace steel from construction materials that have become corroded over time. According to the experts, reducing the amount of steel which needs to be replaced due to corrosion could have significant effects on the amount of greenhouse gases produced to make steel.



“Given society’s reliance on coal fuel, iron and steel production is one of the largest greenhouse gases emitters of any industry. But most of the costs associated with the industry actually stem from the energy that goes into creating steel, and that energy is lost as the steel reverts to rust, which is similar to its original form of iron ore,” explained study senior author Gerald Frankel, a professor of Materials Science and Engineering at OSU.&nbsp;&nbsp;



By using historical carbon dioxide intensity data in order to estimate CO2 levels per year starting from 1960, the scientists found that, in 2021, steel production accounted for 27 percent of the carbon emissions of the global manufacturing sector, and approximately 10.5 percent of the total carbon emissions worldwide, while corroded steel emissions accounted for about 1.6 to 3.4 percent of emissions.



Fortunately, due to regulations placed on the steel industry, technological advancements in the steel industry have resulted in a 61 percent reduction in energy consumption over the past half a century. Nonetheless, policy makers and industry officials should still act urgently to amend and coordinate international policy concerning steel production and corrosion management.



“Coordinated international strategies, as well as decreasing global steel demand, by using best practices for corrosion mitigation, could better improve global corrosion management strategies and drastically reduce the rise in greenhouse gas emissions we’re seeing due to repeatedly replacing corroded steel,” Frankel said.



If such actions are not undertaken soon, greenhouse emissions caused by the steel industry could spike to 27.5 percent of the global carbon emissions by as early as 2030, with corroded steel representing four to nine percent of that number. This could have dire impacts on the Earth’s climate.



“Global warming is a societal challenge that takes coordination of a lot of multidisciplinary approaches. Our work is bringing to light an issue that seems to have gone under the radar in terms of the importance of adding to the problem,” Frankel concluded.



The study is published in the journal <a href="https://www.nature.com/articles/s41529-022-00318-1">npj Materials Degradation</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



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Steel corrosion is a major contributor to climate change

Each year, the United States spends almost a trillion dollars...

According to a new study led by an international team of scientists, China is currently a nighttime “hotspot” for the production of nitrate radicals (PNO3) that may have a significant impact on health-threatening levels of ozone and fine particulates (PM2.5) in the atmosphere. 



While the United States and Europe experienced a decline in nocturnal production of NO3, China has recently experienced a rapid increase in these pollutants. The experts believe that this may have serious implications not only for China, but also for other developing countries such as India.



“Nitrogen oxides derived from combustion and natural sources are reactive gases that regulate the formation of key air pollutants including both ozone (O3) and PM2.5. Nocturnal oxidation driven by nitrate radicals is an important, but poorly understood, process in atmospheric chemistry – we must understand this better, if we are to formulate effective global pollution mitigation strategies and understand the influence of nitrogen oxides on air quality and climate,” said study co-author Zongbo Shi, an expert in Aerosol Chemistry and Physics at the <a href="https://www.birmingham.ac.uk/index.aspx">University of Birmingham</a>.



The analysis revealed that the current production of NO3&nbsp;radicals increased significantly in three megacity clusters (the North China Plain, the Yangtze River Delta, and the Pearl River Delta), while in eight major Chinese cities - Beijing, Shanghai, Guangzhou, Chengdu, Xi’an, Jinan, Zhengzhou and Shijiazhuang – it is currently comparable to that in Los Angeles in the 1990s, and keeps increasing. Moreover, if ozone <a href="https://www.earth.com/news/air-pollution-linked-to-a-higher-risk-of-stroke/">pollution</a> keeps rising, nighttime oxidation in China will most likely increase further, even if NO3&nbsp;emissions are curbed.



Considering the fact that much lower levels of NO3&nbsp;radicals in both U.S. and Europe have been shown to exert significant impacts on particulate nitrate and organic aerosol formation in those regions, the scientists believe that NO3&nbsp;radical chemistry may play a more critical role in atmospheric oxidation and thus aggravate both O3&nbsp;and PM2.5&nbsp;pollution in China very soon, posing public health problems in this country, as well as abroad.



The study is published in the journal <a href="https://www.nature.com/articles/s41561-022-01122-x">Nature Geoscience</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



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Nocturnal pollution is a rising public health threat in China

According to a new study led by an international team...

Sometimes the common names for <a href="https://www.earth.com/news/grazing-animals-play-a-key-role-in-stabilizing-soil-carbon/">animals</a> can end up being rather confusing. For example, guinea pigs are not related to pigs and neither are they native to Guinea. In the case of American black bears, not all of them are black. In fact, they come in a range of colors, including brown (also known as cinnamon), blond, or bluish-grey, and some even have coats with mixed colors.&nbsp;



Scientists have wondered why there is this diversity in coat color among black bears. Some have hypothesized that the cinnamon coat is a way of mimicking the generally larger grizzly bear (Ursus arctos), which is brown (but can also be black!) This may provide some form of camouflage or defense for the American black bears.&nbsp;



In new research from scientists at <a href="https://www.hudsonalpha.org/">HudsonAlpha</a>, the University of Memphis, and the University of Pennsylvania, the answer to this question has been discovered in the genomes of the black bears, and it involves a mutation in a pigment gene that happened a very long time ago. The research paper is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.



Dr. Emily Puckett is an assistant professor of Biological Sciences at the University of Memphis. She has devoted her career to learning more about the evolution and genetics of bears. With help from partners in state, provincial, and federal wildlife agencies, she collected hundreds of DNA and hair samples from North American bears. Dr. Puckett teamed up with Dr. Greg Barsh, an animal pigmentation expert at HudsonAlpha, to figure out why black bears aren’t always black.



Melanin is the pigment that gives mammals their coat colors. It is produced in the skin by cells known as melanocytes. There are two types of melanin: eumelanin is black or brown, and pheomelanin is red or yellow. It is widely accepted that genetic variation in melanin biosynthesis is what gives rise to differences in hair, eye, and skin color.&nbsp;



The researchers studied photos of bears and analyzed their hair samples. They found that the cinnamon-colored black bears produce reduced amounts of eumelanin, just like grizzly bears. They then sequenced the genomes of nearly 200 bears and identified several different missense mutations in the gene&nbsp;called TYRP1&nbsp;that codes for making the enzyme tyrosinase-related protein 1.&nbsp;



Cinnamon-colored black bears have a mutation called&nbsp;TYRP1R153C,&nbsp;while most (but not all) grizzly bears have a mutation called&nbsp;TYRP1R114C. The&nbsp;TYRP1&nbsp;gene produces the enzyme within the melanocytes, and this enzyme helps produce eumelanin, which explains why the cinnamon and grizzly bears have less of this specific pigment.&nbsp;



In addition, studies carried out in the lab of Dr. Mickey Marks at the University of Pennsylvania determined that the TYRP1R153C and TYRP1R114C&nbsp;mutations interfere with melanin synthesis and distribution.



“When we looked at other species, we were surprised to find the&nbsp;TYRP1R153C&nbsp;variant responsible for cinnamon&nbsp;U. americanus&nbsp;is identical to one previously described as a cause of oculocutaneous albinism (OCA3) in humans,” says Dr. Barsh. OCA3 is characterized by reddish skin and hair and frequent visual abnormalities and is most common in people of African or Puerto Rican ancestry. But according to Puckett, bears with&nbsp;TYRP1&nbsp;mutations have normal skin and can see just fine.



The&nbsp;TYRP1R153C&nbsp;variant was primarily found in bears from the southwest United States, and at lower frequencies moving northward to Southeast Alaska and the Yukon Territory.&nbsp;The TYRP1R153C&nbsp;mutation was associated with the cinnamon color in black bears, as well as with the chocolate and light brown colors, meaning it accounts for almost all of the color diversity among&nbsp;U. americanus.



The researchers used their data to learn more about the&nbsp;TYRP1R153C&nbsp;mutation. One hypothesis is that it may first have occurred in grizzly bears and then been&nbsp; transferred to black bears, but demographic analysis indicated that this was not what happened. Instead, the&nbsp;TYRP1R153C&nbsp;mutation arose spontaneously about 9,360 years ago in black bears living in the western United States, then spread as the bears moved and became distributed across their current geographic range.



“Based on its wide range today, the&nbsp;TYRP1R153C&nbsp;mutation that arose in black bears over 9,000 years ago probably gave an advantage to the cinnamon-colored bears,” says Dr. Puckett. “We used genetic modeling and simulations to predict the selective forces acting on the cinnamon morph. But our predictions ruled out the grizzly mimicry hypothesis as well as another hypothesis having to do with thermoregulation.”



The research team proposed a new explanation for the persistence of the coat color variant: crypsis. This refers to the ability of an animal to conceal itself by blending into the surrounding environment, usually by having similar coloration or patterning as the background. The researchers suggest that this is not only important for prey species or ambush predators, but also for large-bodied species that need to blend into their habitat.&nbsp;



“These results illustrate how genetic variation in melanin biosynthesis can underlie iconic phenotypes and inform our understanding of color variation and recent evolution in large carnivores,” says Dr. Barsh.



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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



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Why are some black bears actually brown?

Sometimes the common names for animals can end up being...

A new study led by&nbsp;the&nbsp;<a href="https://www.nord.no/en/Pages/default.aspx">Nord University</a> in Norway in collaboration with the&nbsp;<a href="https://www.icm.csic.es/es">Institut de Ciències del Mar</a>&nbsp;(ICM-CSIC) in Spain has found that the rise in <a href="https://www.earth.com/news/arctic-temperatures-rise-when-plants-stop-breathing/">temperature</a> in the Arctic and sub-Arctic regions caused by global warming are promoting the settlement in these areas of species that previously lived in warmer, southern regions. These findings suggest that climate change is leading to a redistribution of species not only in the much more studied warmer areas of our planet, but also in colder regions which are warming at a much faster rate than the rest of the planet.



The scientists collected data from over 20,000 trawl surveys in the Norwegian and Barents Seas between 1994 and 2020. “In 1994, an average of eight fish species were caught in each trawl in the Norwegian and Barents Seas, while in 2020 the number rises to more than 13, which represents an increase of 66 percent. The results of the study also shown increases, albeit less significant, in the richness of adjacent areas,” said study lead author&nbsp;Cesc Gordó-Vilaseca, a doctoral student in Biosciences at the Nord University.&nbsp;



The analysis revealed that, of the 193 species included, 71 relatively warm-water species are now more common in the Arctic and sub-Arctic regions, while 23 species which were previously more common in the north are now occurring there less frequently. However, the study also documented the expansion of some Arctic species that seem to adapt well to rising temperatures, such as the commercially valuable common cod (Gadus morhua).&nbsp;



“The shift in frequency of species, sometimes favored by high temperatures and sometimes not, could lead to a reconfiguration of ecological interactions and, therefore, could cause changes in the structure and functioning of the entire ecosystem,” warned co-author Marta Coll, a researcher at the ICM-CSIC.



These findings could contribute to the design of more effective conservation and management strategies. In future research, the scientists aim to analyze in more detail the changes at the level of the entire ecosystem that may be caused by rising temperatures in the Arctic, as well as the effects on fisheries management and protection measures such changes may cause.



The study is published in the journal <a href="http://dx.doi.org/10.1073/pnas.2120869120">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



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Arctic biodiversity will get a boost from rising temperatures

A new study led by&nbsp;the&nbsp;Nord University in Norway in collaboration...

For decades, immunobiologists have pondered what are the long-term effects of infections on people’s immune systems. For instance, after the organism fights off a pathogen, does the immune system return to a previous baseline, or could a single infection change it in ways that alter how it will respond not only to an already familiar virus or bacteria but also to a new pathogenic threat?



Now, a team of researchers led by <a href="https://www.yale.edu/">Yale University</a> and the <a href="https://www.niaid.nih.gov/">National Institute of Allergy and Infectious Diseases</a> (NIAID) has systematically analyzed immune responses of healthy people who had received the flu vaccine, and compared the responses between those who had never been infected with SARS-CoV-2 and those who experienced mild cases but recovered.



The analysis revealed that the immune systems of men previously infected with the new coronavirus responded more robustly to flu vaccines than previously-infected women or people who had never been infected with SARS-CoV-2. These findings suggest that the immune statuses of men previously infected with SARS-CoV-2 was altered in ways that changed their response to a different type of future exposure.



“This was a total surprise,” said study senior author John Tsang, an immunobiologist at Yale. “Women usually mount a stronger overall immune response to pathogens and vaccines, but are also more likely to suffer from autoimmune diseases.”&nbsp;



According to the scientists, this discovery could also be linked to an intriguing aspect noticed already early in the <a href="https://www.earth.com/news/the-origins-of-covid-19-will-most-likely-remain-a-mystery/">Covid-19</a> pandemic: men appeared much more likely to die from a runaway immune response than women after contracting Covid. The new study shows that even mild cases of Covid-19 may trigger stronger inflammatory responses in males than females, resulting in stronger functional changes to the male immune system, even a long time after recovery.



When analyzing the participants’ response to flu vaccinations, the experts found that males previously infected with SARS-CoV-2 produced more antibodies to influenza and increased levels of interferons (proteins produced by cells in response to infections or vaccines). This was surprising since, in general, healthy females have stronger interferon responses than males.



Since hundreds of millions – if not, according to some estimates, several billions – of people worldwide have been infected with the new coronavirus so far, and the emergence of long-Covid symptoms in some people is currently a major health concern, understanding the lingering effects of Covid on the immune system is crucial.&nbsp;



“Our findings point to the possibility that any infection or immune challenge may change the immune status to establish new set points. The immune status of an individual is likely shaped by a multitude of prior exposures and perturbations,” Sparks concluded.&nbsp;



The study is published in the journal <a href="https://www.nature.com/articles/s41586-022-05670-5">Nature</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



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What are the lingering immune system effects of Covid?

For decades, immunobiologists have pondered what are the long-term effects...

Mountains host about half of the world’s biodiversity hotspots, and action is urgently needed to protect these ecosystems. According to Professor Robert Marchant at the <a href="https://www.york.ac.uk/">University of York</a>, these critically important <a href="https://www.earth.com/news/green-turtle-recovery-greatly-depends-on-foraging-habitats/">habitats</a> should be prioritized in biodiversity policies.



Professor Marchant is calling on national governments to focus on mountain ecosystems while addressing the climate and biodiversity crises. He says that national policy simply isn’t keeping pace with land use change, development, population growth and the impacts of climate change on global mountain systems.



“Government environmental and business policies are rarely joined up and we are seeing continued widespread land degradation in mountain habitats. This includes uncontrolled grazing, deforestation, or overdevelopment - and much of it is resulting from weak policies and changing tenure laws," explained Professor Marchant.



Even though mountain ecosystems are particularly vulnerable to climate change and human development, they do not receive the necessary attention and investment from their governments.&nbsp;



In Kenya, for example, the area around Mount Kilimanjaro has endured a major increase in population density and agriculture over the last two decades. Companies have bought land to drill boreholes and extract water from the mountain’s aquifer.



“Once you’ve paid for that borehole, that water is a free resource to you. But these services are provided by nature – and no one is presently paying for either the water resources or for stewardship of that land. Asking companies to pay for this kind of service, by issuing controllable permits for example,&nbsp; would be a step towards treating our mountain resources with more respect.”



Professor Marchant is calling on countries to invest more in mountain ecosystem restoration activities, and to develop effective climate change policies. His policy brief will be presented later this month at the United Nations Biodiversity Conference (COP15) in Montreal, Canada.



"We are hoping for some progress at COP15, but what is really needed is an international treaty or code of practice that accepts the value of our mountain ecosystems, and I suspect that is some way off.”



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



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Mountain ecosystems are in urgent need of protection

Mountains host about half of the world’s biodiversity hotspots, and...

<a href="https://www.earth.com/news/oxytocin-promotes-cooperation-among-humans/">Oxytocin</a> – the so-called “love hormone” – has been considered for decades to be essential for the development of social attachments in a variety of animal species. However, according to a new genetic study led by the <a href="https://www.ucsf.edu/">University of California, San Francisco</a> (UCSF) and <a href="https://www.stanford.edu/">Stanford University</a>, prairie voles can still form enduring attachments with their mates and provide parental care even without oxytocin receptor signaling.&nbsp;



Prairie voles are one of the few monogamous mammalian species, forming life-long partnerships called “pair-bonds.” Pair-bonded voles share parental responsibilities, and prefer the company of their partners over other members of the opposite sex, actively rejecting potential new partners. Previous research which used drugs to block oxytocin from binding to its receptor found that voles lacking oxytocin binding were unable to pair-bond.



However, by using a groundbreaking genetic manipulation technique called CRISPR to generate prairie voles lacking oxytocin receptor signaling, the researchers found that these genetically-altered voles could still form pair-bonds just as easily as normal voles.



“We were all shocked that no matter how many different ways we tried to test this, the voles demonstrated a very robust social attachment with their sexual partner, as strong as their normal counterparts,” said study lead author Devanand Manoli, a neuroscientist at UCSF.



Following this surprising discovery, the experts investigated whether oxytocin receptor signaling is similarly dispensable for other functions, such as parturition, parenting, and milk release during lactation. “We found that mutant voles are not only able to give birth, but actually nurse,” reported co-author Nirao Shah, a neuroscientist at Stanford. In fact, both male and female mutants engaged in usual parental behavior, such as huddling, licking, or grooming, and were capable of rearing their offspring to weaning age.



However, the mutant voles had limited milk release compared to the normal ones, which caused fewer of their pups to survive to weaning age. In addition, the pups that managed to survive were smaller compared those of normal voles. The fact that voles could nurse at all is highly different from what has been observed in studies involving oxytocin-deficient mice. According to the researchers, this could be due to the inbred nature of lab mice strains in contrast to the genetically heterogenous voles.&nbsp;



“It could be that inbreeding in mice has selected for a large dependence on oxytocin signaling, or this may represent a species-specific role of oxytocin receptor signaling,”&nbsp;Shah explained.



“For at least the last ten years people have been hoping for the possibility of oxytocin as a powerful therapeutic for helping people with social cognitive impairments due to conditions ranging from autism to schizophrenia. This research shows that there likely isn’t a magic bullet for something as complex and nuanced as social behavior,” Manoli concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1016/j.neuron.2022.12.011">Neuron</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



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Prairie voles can form close bonds without oxytocin

Oxytocin – the so-called “love hormone” – has been considered...

The Late <a href="https://www.earth.com/news/permian-mass-extinction/">Permian Mass Extinction</a> (LPME) was the largest such in event in the Earth’s history, decimating between 80 and 90 percent of life on our planet. However, the causes of this devastating event and the ways in which it unfolded are not yet fully understood. By analyzing mercury from Siberian volcanoes that ended up in sediments in Australia and South Africa, a team of researchers led by the <a href="https://uconn.edu/">University of Connecticut</a> (UConn) has managed to shed more light on this mass extinction’s causes and timeline.&nbsp;



Although scientists have long argued that the rapid warming associated to this event was linked to massive volcanism occurring at a large deposit of lava called the Siberian Traps Large Igneous Province (STLIP), clear evidence for this was still lacking. While volcanoes leave helpful clues in the geological record – such as traces of carbon dioxide and methane launched into the atmosphere and deposited around the globe – it is hard to directly link something like that to the extinction event. 



“As geologists, we’re looking for a signature of some kind - a smoking gun - so that we can absolutely point to the cause,” said study co-author Tracy Frank, an expert in Earth Sciences at UConn.



However, the researchers believe that they finally might have found such a “smoking gun” – mercury, one of the heavy metals associated with volcanic eruptions, analyzed from sediments from the Sydney Basin in Eastern Australia and the Karoo Basin in South Africa.&nbsp;



“It turns out that volcanic emissions of mercury have a very specific isotopic composition of the mercury that accumulated at the extinction horizon. Knowing the age of these deposits, we can more definitively tie the timing of the extinction to this massive eruption in Siberia. What is different about this paper is we looked not only at mercury, but the isotopic composition of the mercury from samples in the high southern latitudes, both for the first time,” explained study lead author Jun Shen, an expert in volcanism at the <a href="https://en.cug.edu.cn/">China University of Geosciences</a> in Wuhan.



“As a starting point, geologists have pinpointed the timing of the major extinction event at 251.9 million years with a high degree of precision from radiogenic isotope dating methods. Researchers know that is when the major extinction event happened in the marine environment and it was just assumed that the terrestrial extinction event happened at the same time,” added co-author Christopher Fielding, a professor of Earth Sciences at UConn.



According to Fielding’s previous research though, the extinction event on land happened about 200,000 to 600,000 years earlier. “That suggests that the event itself wasn’t just one big whammy that happened instantaneously. It wasn’t just one very bad day on Earth, so to speak, it took some time to build and this feeds in well into the new results because it suggests the volcanism was the root cause,” he explained. “That’s just the first impact of the biotic crisis that happened on land, and it happened early. It took time to be transmitted into the oceans. The event 251.9 million years ago was the major tipping point in environmental conditions in the ocean that had deteriorated over some time.”&nbsp;



“The main point is that we now have a chemical signature in the form of mercury isotope signatures, that definitively ties the extinction horizon in these terrestrial sections that provide a record of what was happening on land due to Siberian Traps volcanism.”



The study is published in the journal <a href="https://www.nature.com/articles/s41467-022-35272-8">Nature Communications</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



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New clues about Earth's largest mass extinction event

The Late Permian Mass Extinction (LPME) was the largest such...

A new study led by the <a href="https://www.uq.edu.au/">University of Queensland</a> has revealed that some of Asia’s largest animals are thriving near humans. The experts say that <a href="https://www.earth.com/news/tigers-are-threatened-by-road-and-railway-development/">tigers</a>, elephants, and other animals are essentially defying 12,000 years of extinction trends.



Based on paleontological records, the researchers established the historic distribution of Asia’s 14 largest species. The experts compared this data with the present-day distribution of the same species in tropical forests.



According to study lead author and PhD student Zachary Amir, four species showed increased populations in areas with human infrastructure, including tigers, Asian elephants, wild boars, and clouded leopards.



“These results show that, under the right conditions, some large animals can live nearby humans and avoid extinction,” said Amir. “These results challenge the narrative within some conservation circles that humans and megafauna are incompatible."



“Globally there is a trend towards ‘trophic downgrading,' a term referring to the disproportionate loss of the world’s largest animals. Trophic downgrading is usually worst near humans because hunters target larger species."



“But in the case of tigers, elephants, wild boars and clouded leopards, their Asian populations are higher near humans. This may be the outcome of tougher anti-poaching efforts in the national parks that are closer to human settlements and are more frequently visited by tourists.”



On the other hand, the results showed that deforestation is still impacting species - with clouded leopards taking the hardest hit in deforested areas.&nbsp;



Even still, Amir said the research suggests that if the large animal species were not hunted, they could live in relatively small habitats and near humans.



“Previously, there have only been a few examples of large Asian species thriving in small habitats near humans, notably in Mumbai, India where leopards in an urban park prey on stray dogs,” said Amir. “Thankfully, we found that a wider range of animals can coexist with humans.”



At one particular study site in Singapore, poaching has been eliminated and forest restoration efforts are underway. Here, the researchers found that two large animal species are thriving again.



“Singapore has actually experienced the natural re-wilding of sambar deer and wild boars, which are now frequently observed in an urban forest, the Bukit Timah Nature Reserve,” said Amir. “If we replicate those protection efforts in larger forests and other counties, we may see positive impacts right around the world. But before this can happen, humans need to get our act together and limit poaching.”



The study is published in the journal <a href="http://dx.doi.org/10.1126/sciadv.abq2307">Science Advances</a>.



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



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Large Asian animals are successfully coexisting with humans

A new study led by the University of Queensland has...

Plants in the mint family are rich in chemical molecules that give distinctive scents and flavors to their leaves. The mint family (Lamiaceae) is the sixth largest family of flowering plants and includes many familiar species, apart from mint itself, such as basil, rosemary, peppermint, lavender, sage and coleus. The aromatic and flavorful compounds produced by these plants function to attract <a href="https://www.earth.com/news/gardeners-can-make-small-changes-to-benefit-pollinators/">pollinators</a> and to deter herbivores, and they have been essential in driving the diversification of this large group of plants.



Researchers from <a href="https://msu.edu/">Michigan State University</a> have been studying the great variety of metabolites found in mint plants for many years, and have recently focused on a group of molecules called terpenoids. These compounds are essential in protecting the plants from predators and pathogens, and are also common ingredients in green and sustainable agrochemicals, antioxidants, cosmetics and fragrances.&nbsp;



“People easily recognize members of the mint family for their specialized metabolites,” said Dr. James K. Billman, Jr. and Professor&nbsp;<a href="https://biomolecular.natsci.msu.edu/faculty/alphabetical-directory/bjoern-hamberger/">Björn Hamberger</a>. “Metabolites are an efficient way for plants to defend themselves because they can’t run away.”



Professor Hamberger worked previously with Robin Buell, a former MSU genomics researcher, who sequenced the genomes from several different species in the mint family. This collaboration with Buell’s team led graduate students Abigail Bryson and Emily Lanier to discover how several genomes of the mint family have evolved over the past 60 million to 70 million years and how their chemistries have emerged.&nbsp;



“Over millions of years, plants have adapted and evolved for their particular niches where they thrive, and that means that these chemistries are diverse and have clearly adjusted to their environment,” said Professor Hamberger. “So, we try to identify and discover pathways to these specialized metabolites that plants make.”



According to the researchers, this family of plants have diversified the natural characteristics of their metabolites throughout their evolution, leading to the great variety of different chemical compounds found in today’s members of the group. In order to understand the mechanisms by which such diversity has evolved, the researchers took an interdisciplinary approach and analyzed the genetic and chemical pathways involved in terpenoid biosynthesis in different species in the mint family.



Bryson identified the genomic framework of terpenoid biosynthesis, and Lanier analyzed the chemical pathways. Together, Lanier and Bryson discovered something highly unusual in the beautyberry (Callicarpa americana) genome from the mint family. It has a large biosynthetic gene cluster (BGC), which is a group of genes, located close together in the genome, that are involved in the same metabolic pathways. Additionally, Bryson and Lanier found variants of this BGC in six other species in the mint family.



“We are learning that the physical location of genes within the genome is important,” Bryson said. “It can drive evolution of specialized metabolic pathways in the plant, leading to a vast diversity of interesting natural plant compounds.”&nbsp;



The BGC cluster of the beautyberry plant contains genes that encode two distinct terpenoid pathways. The team found these terpenoids accumulate in various parts of the plant, such as the leaves and roots, and may play distinct roles in helping the plant to adapt to its environment.&nbsp;



“It’s the same base molecule, but each species is making its own version and modifying it in different ways to fit their survival needs,” Lanier said.&nbsp;



Professor Hamberger describes it like a recipe that everyone has a copy of and changes to suit their requirements and preferences.&nbsp;



The researchers hope that a better understanding of the ways in which these compounds have been modified by different plant species will lead to potential future applications that could include new medicines and pesticides. We already use some of the compounds as flavor additives, fragrances, and anti-herbivory agents.



Previous research has led to unique medical uses for mint plants. For example, Indian Coleus can be used as a natural treatment for glaucoma and Texas sage is a natural antimicrobial that is effective against tuberculosis. The new molecular adaptations that have been found in the current study open the door for future applications of natural plant products from the mint family.



“Our team has been excited about the opportunities within the mint family,” said Professor Hamberger. “Those mint enzymes, as in the American beautyberry plant, give us the ability to make plant-natural products in the lab, including – hopefully in the future – natural good-smelling mosquito repellants.”



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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



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Plants in the mint family may help produce new medicines

Plants in the mint family are rich in chemical molecules...

Scientists have long argued that self-awareness is a rare phenomenon in the animal kingdom, with only a few mammals, some birds, and some fish appearing to have it. However, according to a new study published on the <a href="https://www.biorxiv.org/content/10.1101/2022.11.04.515260v1.full">bioRxiv</a> preprint server, some species of wild penguins, such as the <a href="https://www.earth.com/news/adelie-penguins-antarctica/">Adélie penguins</a> from Antarctica, may also have a certain degree of self-awareness.



While in humans, self-awareness is an easy thing to test, in animals it is much more complicated to reliably assess this capacity. Most studies aiming to test the presence of self-awareness in animals have used the so-called “mirror test,” in which animals are allowed to see themselves in a mirror while scientists observe their reactions. For instance, if animals touch a red mark on their own face that they can only see in the mirror, experts usually assume they have a degree of self-awareness.



In the new study, the researchers traveled to Svenner Island in eastern Antarctica to observe the behavior of Adélie penguins, and conducted four experiments. In the first one, they placed several mirrors on the ground nearby the penguins and observed the animals’ behaviors while looking down at the mirrors. The second experiment involved constructing a cardboard corral around some of the penguins which directed them toward mirrors at the ends of an enclosure, while the third involved placing small stickers on the mirrors that, when viewed, appeared as if they were on the penguins looking at them. In a final experiment, they placed a bib on random penguins in front of a mirror and observed their reactions.



In the first experiments, the scientists detected no response, which was actually an important finding, since many animals fail such a test, believing that the creatures they are seeing in the mirror are actually conspecifics and respond accordingly. While in the second experiment, the penguins moved in ways that suggested they might be examining themselves, in the third one, they became agitated when looking at mirrors with stickers on them and actively tried to remove the stickers. However, they did not respond at all when seeing themselves wearing a bib. Although the results remain rather ambiguous, the researchers argued that they may suggest the presence of at least some degree of self-awareness in penguins.



“Future studies, integrating the socioecology and cognitive ethology of penguins, may provide insights into whether our experimental paradigms could provide evidence to confirm the presence of self-awareness and even of self-recognition in this species and examine whether the observed social awareness may have evolved due to the social needs of individual penguins to engage in cooperative behavior with conspecific individuals, while maintaining their independent decision-making capacities, throughout their communal lives,” the authors concluded. 



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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



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Penguins may have a degree of self-awareness

Scientists have long argued that self-awareness is a rare phenomenon...

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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Flu viruses are more flexible than expected

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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Detecting mercury contamination with the tap of a finger

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Kainji Lake, a reservoir on the Niger River.



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



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



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



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



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



Video/ Image Credit: European Space Agency&nbsp;



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



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Kainji Lake in north central Nigeria

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



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



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



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



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



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



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



Video Credit: Amanda Nguyen/University of Illinois



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



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Designing crops that can beat the heat

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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



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How does salt makes things taste better?

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



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



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



Video/ Image Credit: ESA



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



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Santiago, Chile in South America

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

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



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



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



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



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



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



Video Credit: Johns Hopkins&nbsp;



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



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Interactive map of the universe includes 200,000 galaxies

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



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



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



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



Video Credit: NASA Goddard&nbsp;



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



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Remote sensing will revolutionize the way we monitor trees

[sendtonews key="EjmSP20gQK-2593093-12187" type="single"] Today's Video of the Day from NASA...

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Dublin, the capital and largest city of Ireland. Beyond its pub culture, Dublin is known as a modern culinary destination and a UNESCO City of Literature.



"Dublin is located near the midpoint of Ireland’s east coast in the province of Leinster. The city, which covers an area of around 115 square kilometers, is bordered by the Dublin Mountains, a low mountain range to the south, and is surrounded by flat farmland to the north and west," says ESA.



"The city straddles the River Liffey, which rises in the Wicklow Mountains and flows around 80 kilometers eastwards through the city of Dublin, in which it is canalised and bordered with quays. It then empties into Dublin Bay, an arm of the Irish Sea."



Dublin has an abundance of green spaces, including one of the largest enclosed public parks in any European capital city. Phoenix Park, which was originally formed as a royal hunting park in the 1660s, includes 707 hectares of green space.



Video Credit: ESA&nbsp;



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



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The city of Dublin on Ireland's east coast

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the province of Zaragoza in northeast Spain. The image was captured by the Copernicus Sentinel-2 mission.



"Together with the provinces of Huesca and Teruel, Zaragoza formed the old kingdom of Aragon. Its capital, also called Zaragoza (not visible in this image) is home to around half of Aragon’s population," says ESA.



"The Ebro River can be seen winding its way through the province from west to east in this image. Between its source in the Cantabrian Mountains in the northwest and its delta on the Mediterranean coast, the Ebro River is fed by more than 200 tributaries as it flows 910 km across much of northern Spain."



Since rainfall is very scarce in this region, irrigation in the Ebro basin is critically important. In the valleys surrounding the Ebro River, many fields are used for growing crops such as corn, wheat, and barley.



Video/ Image Credit: ESA



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



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

The province of Zaragoza in northeast Spain

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



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



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



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



Video Credit: NASA Goddard



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



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

Wetlands are a major source of methane emissions

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> reveals the evolution of the Columbia Glacier in southeastern Alaska. Columbia is among the fastest shrinking glaciers in the world, and the video documents its rapid retreat over the years.&nbsp;



Columbia Glacier is a large, multi-branched calving glacier that flows out of the Chugach Mountains to the Prince William Sound.&nbsp;



According to USGS, Columbia had a long history of stability prior to 1980, with a length 41 miles, and small, short-lived advances or retreats.



In the years since 1980, however, satellite images have captured Columbia’s alarming retreat. By using false-color images, scientists can distinguish between snow and ice, open water, vegetation, and rocky debris on the glacier’s surface.



The series of false-color images featured in today's video were acquired over the span of 35 years. You can see that by 2021, the glacier’s main branch had retreated about 15 miles from its initial position.



The Columbia Glacier has also lost more than 50 percent of its volume, mostly due to calving. <a href="https://www.earth.com/video/nasa-reveals-3d-visual-of-an-atmospheric-river/">NASA</a> reports that while climate change likely started the retreat, mechanical processes kept the disintegration going.



The NASA images are provided by Jesse Allen, Robert Simmon, Joshua Stevens, and Lauren Dauphin using data from Landsat satellites, from the U.S. Geological Survey, and data from MODIS on NASA’s Terra satellite. The structure of Columbia’s moraine played a large role in the stability of the glacier before 1980. 



Like other tidewater glaciers, the Columbia built up a moraine over time, and the mixture of ice and rock functioned like a dam keeping out the sea. It was supported on one end by the shoreline and by the underwater terminal moraine at the other.



Video Credit: NASA Earth Observatory/&nbsp; NASA’s Scientific Visualization Studio



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



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

The rapid retreat of the Columbia Glacier

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



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



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



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



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



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



Video &amp; Image Credit: ESA



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



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

The Pyrenees Mountains in southwest Europe

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



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



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



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



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



Video Credit: Stowers Institute for Medical Research&nbsp;



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



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

How the immune system responds to injury

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



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



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



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



Video/ Image Credit: NASA Goddard



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



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2022 illustrated the consequences of a warming climate

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Earth,Like,Exoplanet,3d,Render

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



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



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



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



Video Credit: NASA Goddard



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



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



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

Two distant planets may be "water worlds"

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



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



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



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



Video Credit: NASA Goddard&nbsp;



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



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

Satellites reveal how Earth's systems are interconnected

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

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



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



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



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



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



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



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



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

Tiger sharks are shifting poleward as temperatures rise

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