The development of a big brain in humans and its connection to social bonding has been a hot topic of debate, and secrets found in fossil teeth may hold the answers.



Researchers have been studying the fossilized teeth of an early Homo from Georgia, dating back approximately 1.77 million years. The research was made possible by the European Synchrotron in Grenoble, France.



The findings suggest that despite having a small brain and reaching adulthood at a similar pace to great apes, these early humans had a prolonged childhood. 



This could mean that the large brain of modern humans resulted from an extended childhood along with cultural transmission across generations instead of vice versa.



<h2 class="wp-block-heading" id="h-long-childhood-big-brains">Long childhood, big brains</h2>



A team of researchers - including specialists from Switzerland's <a href="https://www.uzh.ch/en.html" target="_blank" rel="noreferrer noopener">University of Zurich</a>, the European Synchrotron Radiation Facility and Georgia's National Museum - have challenged the theory that modern humans' extended childhood is directly linked to their large brains.



The team analyzed dental development in an early Homo that was almost an adult. The results suggest that though these early humans reached adulthood at a similar age as <a href="https://www.earth.com/news/buronius-manfredschmidi-tiny-great-ape-species-lived-11-million-years-ago/" target="_blank" rel="noreferrer noopener">great apes</a>, their tooth development followed a longer timeline similar to modern humans.



This proposes the distinct possibility of a longer dependency on adults and an elongated childhood for these early humans.



Remarkably, the brain size of these early Homo specimens was only marginally larger than that of a chimpanzee. This made the researchers question the link between the prolonged development and cultural transmission across generations.



An extended childhood within a three-generation context might have allowed the immature members of the group to effectively assimilate growing amounts of knowledge. 



Eventually, this led to the development of larger brains and longer life spans, traits characteristic of modern humans.



<h2 class="wp-block-heading" id="h-dental-development-in-early-homo">Dental development in early Homo</h2>



An enduring assumption has been that humans' extended growth period is a consequence of <a href="https://www.earth.com/news/our-brain-sizes-are-growing-possibly-lowering-dementia-risk/" target="_blank" rel="noreferrer noopener">increased brain volume</a> since a larger organ requires more energy resources to grow. But analysis of the fossil's dental growth has caused researchers to question this hypothesis.



The research team used synchrotron imaging to study the dental development of a near-adult fossil of early Homo from the Dmanisi site in Georgia, dated to around 1.77 million years ago. 



<div class="wp-block-sendtonews-playerselector">[sendtonews key="CWxiqQg039-4024544-12187" type="single"]</div>



“Childhood and cognition do not fossilize, so we have to rely on indirect information. Teeth are ideal because they fossilize well and produce daily rings, in the same way that trees produce annual rings, which record their development,” noted study first author Christoph Zollikofer from the University of Zurich.



<h2 class="wp-block-heading" id="h-unexpected-findings-and-a-new-perspective">Unexpected findings and a new perspective</h2>



“Dental development is strongly correlated with the development of the rest of the body, including brain development," explained study co-author Paul Tafforeau, scientist at the ESRF.



"Access to the details of a <a href="https://www.earth.com/search-results/?search=fossil%20hominid&amp;start=0" target="_blank" rel="noreferrer noopener">fossil</a> hominid's dental growth therefore provides a great deal of information about its general growth."



After almost two decades of research beginning in 2005, the initial results startled researchers. 



“We expected to find either dental development typical of early hominids, close to that of the great apes, or dental development close to that of <a href="https://www.earth.com/news/neanderthal-genes-still-influence-modern-humans/" target="_blank" rel="noreferrer noopener">modern humans</a>," said Tafforeau.



"When we obtained the first results, we couldn’t believe what we saw, because it was something different that implied faster molar crown growth than in any other fossil hominin or living great ape."



In the following years, the team conducted five series of experiments and completed four full analyses, employing various methods as dental synchrotron imaging technology advanced.



As the consistent results suggested significant implications for the "big brain - long childhood" hypothesis, the scientists needed to think creatively to interpret this fossil's findings.



“It's been a slow maturation, both technically and intellectually, to finally arrive at the hypothesis we are publishing today,” said Tafforeau.



<h2 class="wp-block-heading" id="h-longer-childhood-evolution-s-early-experiment">Longer childhood: Evolution's early experiment?</h2>



The dental development of the studied fossil suggested that milk teeth were used longer than in great apes, implying that early Homo children were dependent on adult care for a longer duration.



This could be the first experiment evolution took towards a prolonged childhood. Despite having brains only slightly larger than australopithecines or great apes, early Homo are believed to have lived longer.



The survival of a very old individual with no teeth for several years indicates that the group sufficiently cared for him. This alludes to a three-generation structure, a key aspect of <a href="https://www.earth.com/news/humans-started-cumulative-culture-around-600000-years-ago/" target="_blank" rel="noreferrer noopener">cultural transmission in humans</a>.



The new hypothesis begins with children's growth slowing down as cultural transmission increased. 



The accumulation of information from older to younger individuals had an advantageous effect on resource utilization and the development of complex behaviors, thus favoring a longer childhood. 



Once this mechanism was established, natural selection acted on cultural transmission, not just biological traits. 



<h2 class="wp-block-heading" id="h-big-brains-and-delayed-adulthood">Big brains and delayed adulthood</h2>



As the volume of transferrable information grew, evolution supported a larger brain and delayed adulthood, enabling a longer learning period in childhood and time to grow a bigger brain despite limited food resources.



The large brain of modern humans could be attributed to an extended childhood and a three-generation structure encouraging bio-cultural evolution. These mechanisms may have led to increased brain size, delayed adulthood, and longer lifespan. 



The study of this exceptional fossil could motivate researchers to rethink the evolutionary mechanisms that led to Homo sapiens.



The study is published in the journal <a href="https://www.nature.com/articles/s41586-024-08205-2" target="_blank" rel="noreferrer noopener">Nature</a>.



Image &amp; Video Credit: ESRF/Paul Tafforeau, Vincent Beyrand



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How did humans get big brains? Fossil teeth reveal new clues

The development of a big brain in humans and its connection to social bonding has been a hot topic of debate, and secrets found in fossil teeth may hold the answers. Researchers have been studying the fossilized teeth of an early Homo from Georgia, dating back approximately 1.77 million years. The research was made possible by the European Synchrotron in Grenoble, France. The findings suggest that despite having a small brain and reaching adulthood at a similar pace to great apes, these early humans had a prolonged...

Go to any natural history museum, watch any dinosaur movie, and undoubtedly the big bad will be a <a href="https://www.earth.com/news/flesh-eating-theropods-were-extremely-fast/">theropod</a>. This terrifying, exceptionally toothy group includes Tyrannosaurus, Velociraptor, Allosaurus, and many others. Paleontologists are finally unraveling how the murderous jaws of these predatory dinosaurs evolved.



A new study, published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a> looked at the lower jaws of over 40 theropod dinosaur species. While the most well-known theropods are big and toothy, they also came in many shapes and sizes. Some were small, and some were, in fact, toothless.&nbsp;



By running the different jaws through computer modeling to test their strength, the researchers found that over the course of their evolution, theropod jaws grew progressively stronger. The predatory dinosaurs expanded the rear, or posterior, portion of their jaws (sideways or laterally), and the mechanical strength increased over the course of their over 100-million year history.&nbsp;



“Although theropod dinosaurs are always depicted as fearsome predators in popular culture, they are in fact very diverse in terms of diets. It is interesting to observe the jaws becoming structurally stronger over time, in both carnivores and herbivores. This gives them the capacity to exploit a wider range of food items," explained study lead author Dr. Fion Waisum Ma of the <a href="https://www.birmingham.ac.uk/index.aspx">University of Birmingham</a>.



"Theropod dinosaurs underwent extreme dietary changes during their evolutionary history of 165 million years. They started off as carnivores, later on evolved into more specialized carnivores, omnivores and herbivores. Studying how their feeding mechanics changed is key to understanding the dietary transitions in other vertebrate animals too.”



While it makes sense that the hypercarnivorous meat-eaters would increase their lower-jaw strength, the herbivorous lineages also developed stronger jaws.&nbsp;



“It is fascinating to see how theropod dinosaurs had evolved different strategies to increase jaw stability depending on their diet," said study co-author Dr. Stephan Lautenschlager. "This was achieved through bone remodeling – a mechanism where bone is deposited in regions of the jaw that experience high stresses during feeding.”&nbsp;



This evolutionary pattern is reflected in the ontogeny, or growth, of the individual animals. For example, juvenile tyrannosaurs possessed proportionally slimmer and downturned jaws compared to adult individuals.&nbsp;



“The similarity between jaw strengthening through growth and through time suggests that developmental patterns in juvenile dinosaurs ultimately affected the evolution of the whole group," concluded Dr. Lautenschlager&nbsp; "This likely facilitated the jaw evolution of theropod dinosaurs and their overall success for over 150 million years.”



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By <a href="http://mailto:rugerpaleo@gmail.com">Alex Ruger</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Jaws of predatory dinosaurs grew stronger as they evolved

Go to any natural history museum, watch any dinosaur movie,...

A new study published in the journal <a href="https://dx.doi.org/10.1038/s41562-021-01254-x">Nature Human Behavior</a> has found that playing a recently developed action video game can help children significantly improve their reading skills. Since reading requires skills such as <a href="https://www.earth.com/news/exercise-can-reduce-or-prevent-vision-loss/">vision</a>, attention, working memory, and cognitive flexibility, a research team led by Angela Pasqualotto, a postdoctoral fellow in Psychology at the <a href="https://www.unige.ch/en/">University of Geneva</a>, created a video game aiming to help children develop these capacities.



“The universe of this game is an alternative world in which the child, accompanied by his Raku, a flying creature, must carry out different missions to save planets and progress in the game,” explained Dr. Pasqualotto. &nbsp;“For example, the Raku flies through a meteor shower, moving around to avoid those or aiming at them to weaken their impact, while collecting useful resources for the rest of the game, a bit like what you find in action video games.”&nbsp;



Dr. Pasqualotto and her colleagues enrolled 150 Italian schoolchildren aged between 8 and 12, and divided them into two groups: one group played the action game developed by the team, and the other played <a href="https://scratch.mit.edu/">Scratch</a>, a non-action game which teaches kids how to code, and also requires planning, reasoning, and problem-solving abilities.



After initially testing the children’s reading levels as well as their attentional control, the researchers asked them to play the games for six weeks (two hours per week) under supervision at school. After the end of this period, children’s reading capacities were tested again.



“We found a 7-fold improvement in attentional control in the children who played the action video game compared to the control group,” said Dr. Pasqualotto. “What is particularly interesting about this study is that we carried out three further assessment tests at 6 months, 12 months, and 18 months after training. On each occasion, the trained children performed better than the control group, which proves that these improvements were sustained.”



Moreover, the scientists observed clear improvements not only in reading speed, but also in reading accuracy, together with longer-term increases in the children’s overall school grades. &nbsp;“The effects are thus long-term, in line with the action video game strengthening the ability to learn how to learn,” said study co-author Daphne Bavelier, a professor of Psychology at the University of Geneva.



Researchers are now trying to adapt the videogame in German, English, and French to investigate whether its benefits on reading acquisition can extend to non-phonetic languages too, in which not all letters are pronounced, and thus require further abilities such as a greater reliance on memorization.&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

Playing action video games can improve reading skills

A new study published in the journal Nature Human Behavior...

We live in a diverse world with different ecosystems and <a href="https://www.earth.com/news/shrinking-habitats-alien-species-threaten-native-trout/">habitats</a>. For centuries, scientists have been studying how flora and fauna interact within these natural communities. Some animals are creatures of habit who frequently eat in the same spots, travel on the same roads, and raise their young in the same places. The term "site fidelity" is used by ecologists to characterize the behavior of animals who are fixed in their routines and tend to return to a previously occupied location. 



The habit of many animals, from fish to birds to mammals and insects, to return to regularly frequented areas. Site fidelity is everywhere in nature, whether it's salmon returning to their native streams to breed or birds returning year after year to the same nest site.



According to a new study, while this "consistent" behavior may be beneficial when environmental conditions aren't changing rapidly, the benefits may not be realized in the ever-changing world dominated by humans. The research was focused on a literature review led by the <a href="http://www.uwyo.edu/">University of Wyoming</a>.



When animals get familiar with a location, site fidelity can help them figure out where to obtain good food or safe havens from predators, as well as how to get to and from these resources quickly. On the other hand, the research team discovered a new trend in the scientific literature.



“Animals that have strong site fidelity are having a tough time adjusting to the novel landscapes that are showing up around them as a result of humans,” said study co-lead author Professor Jerod Merkle.



The researchers pointed out that animals with strong site fidelity may not survive or reproduce as well as animals with more flexible behaviors when faced with human disturbances or climate change. When a population consists of a large number of site loyalists, a population decrease might occur due to the changes in the environment.



For instance, there are numerous mule deer winter ranges in Wyoming. With the addition of large natural gas fields, mule deer can make slight range adjustments to avoid infrastructure, but they stick to the same general area rather than abandoning it completely. The continued use of those damaged places may have detrimental implications. In one long-term study, researchers discovered a 40% drop in the mule deer population following large-scale energy development in their winter area.



Climate change also plays a major role in the adverse impacts on site-fidel animals. Under normal climate circumstances, site fidelity is a winning strategy for female northern elephant seals in the Pacific Ocean. In average years, site-faithful seals are better able to acquire food and gain fat compared to their more flexible cousins. But when aberrant climate events - such as extreme El Nios - induce major changes in the ocean ecology, behaviorally flexible seals win out. Female seals with strong site fidelity are unable to gain as much vital fat as they require to reproduce.



“Despite each of us working on very different species from one another, our group came together because we all recognized that there was a clear connection between strong site fidelity and species declines," said study co-lead author Briana Abrahms, an assistant professor at the University of Washington.



"We all thought it was important to call attention to this connection for other researchers and wildlife managers. Recognizing the types of species or behaviors that may suffer most from human-induced environmental change can help develop conservation priorities and actions."



While the analysis paints a bleak picture of the future for animals with high site fidelity, they also offer hope. The experts noted that occasionally, an animal will try something new and succeed. While such instances are uncommon, those "innovators" can be critical to a company's long-term survival in a changing environment.



"While these species appear to be stuck in their ways, many of them also have some unique but subtle ways of dealing with change,” said study co-author Jonathan Armstrong, an assistant professor at Oregon State University. “We just have to be patient and make sure populations don’t crash before such innovators come along,” Armstrong added.



The researchers offer a number of recommendations for researchers and practitioners towards the end of their paper. To begin, long-term monitoring is essential for determining how individuals and populations react to change. Second, they argue that biologists should not always expect animals to use and discover the optimal habitats. This is especially crucial when it comes to restoring new habitat regions, which may not work well for species with high site fidelity because they may not be able to "discover" these regenerated habitats.



As a result, the study authors propose that, rather than off-site mitigation, the conservation of species with high site fidelity should focus on the protection and restoration of highly frequented locations.



The study is published in the journal <a href="https://www.esa.org/frontiers-in-ecology-and-the-environment/">Frontiers in Ecology and the Environment</a>.



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By <a href="http://mailto:ashikha92@gmail.com">Ashikha Raoof</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Animals with strong site fidelity face an uncertain future

We live in a diverse world with different ecosystems and...

A new study led by the <a href="https://www.ku.dk/english/">University of Copenhagen</a> has investigated how different health-promoting signaling <a href="https://www.earth.com/news/origins-life-simple-molecules/">molecules</a> produced by various organs of our bodies following physical exercise are influenced by the time of the day when exercise is performed. Understanding the relationship between circadian rhythms and exercise can have broad impacts on our health, helping us improve our sleep, memory, and metabolic homeostasis.



Most of our cells regulate their biological processes over a 24-hour period, operating in so-called “circadian rhythms.” Thus, the sensitivity of different bodily tissues to the effects of exercise depends on the time of day when exercise is performed. In order to better understand this complex connection, the researchers carried out experiments on mice that exercised either in the early morning or late evening.&nbsp;



Using mass spectrometry to analyze blood samples and tissues from the specimen’s heart, liver, brain, muscle, or fat, the scientists detected hundreds of metabolites and signaling molecules in each type of tissue, and monitored how they were changed by exercising at different times of the day. This resulted in an “Atlas of Exercise Metabolism,” a complex and comprehensive map of exercise-induced molecules found in different tissues following exercise at different times of day.



“A better understanding of how exercise affects the body at different times of day might help us to maximize the benefits of exercise for people at risk of disease, such as obesity and type 2 diabetes,” said study co-author Juleen R. Zierath, an expert in Circadian Biology at the University of Copenhagen.



“Not only do we show how different tissues respond to exercise at different times of the day, we also propose how these responses are connected to induce an orchestrated adaptation that controls systemic energy homeostasis,” added study co-author Jonas Thue Treebak, an associate professor specializing in molecular metabolism at the same university.



This research sheds new light on how tissues communicate with one another, and how exercise can help “realign” in particular tissues faulty circadian rhythms that have previously been linked to increased risks of metabolic diseases, such as obesity or type 2 diabetes. Further research is needed to understand how newly identified exercise-induced signaling molecules in multiple bodily tissues individually or collectively affect health.



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S1550413121006355?via%3Dihub#sec2">Cell Metabolism</a>.&nbsp;



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

How exercise affects the body at different times of day

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

Osteoarthritis (OA) affects 45 percent of all cats, and over 90 percent of those older than 12. The condition is caused by the breakdown of cartilage cushion surrounding the joints, which makes the bones rub against each other, leading to chronic <a href="https://www.earth.com/news/why-does-our-breathing-rate-increase-when-we-feel-pain/">pain</a> and decreased joint movement.&nbsp;&nbsp;



The traditional medical treatments for cat arthritis consist of animal-specific nonsteroidal anti-inflammatory drugs (NSAID), similar to ibuprofen. These drugs can only be used safely for a short period of time, and cannot be given to cats suffering from kidney disease (which is another very common cat affliction).



However, a new drug manufactured by the company <a href="https://www.zoetis.com/index.aspx">Zoetis</a> has now been approved by the <a href="https://www.fda.gov/">U.S. Food and Drug Administration</a> (FDA). Solensia is a cat-specific monoclonal antibody that is injected by the veterinary under the skin once a month, and appears to be highly effective in diminishing the pains caused by OA and thus improving the animals’ mobility and overall quality of life. In two clinical trials, 77 percent of cat owners saw significant improvements in their pets after treatment with Solensia, compared to 67 percent in the placebo groups.



“Feline (arthritis) pain is typically undertreated because of a lack of effective solutions that are safe to use long-term, along with how difficult it can be for cat owners to administer oral medicines,” said Mike McFarland, chief medical officer at Zoetis. “The approval of Solensia is a significant step forward.”



“This is absolutely groundbreaking,” added Dr. Duncan Lascelles, a professor of Translational Pain Research and Surgery at the North Carolina State College of Veterinary Medicine. “I have been in pain research for 30 years and this is the most exciting development that has happened.”



“To be able to be mobile is so desperately important to the quality of life. Cats are described as needing 3D spaces. They need to move on the ground but they also need to be able to get to elevation.”&nbsp;



“Finally, for the first time ever in the U.S., there’s a highly efficacious treatment to manage joint pain in cats. And therefore extend their life, extend their happiness, and extend that beautiful relationship between cats and their owners,” Dr. Lascelles concluded. &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

Revolutionary treatment greatly extends the lives and happiness of cats

Osteoarthritis (OA) affects 45 percent of all cats, and over...

A new study from <a href="https://www.waseda.jp/top/en/">Waseda University</a> reveals that eating slowly and chewing food well increases the body’s energy expenditure and can indeed help obesity and metabolic syndrome.&nbsp;



It may sound counterintuitive, but each time you eat food your body’s metabolic rate increases and you use up extra energy. So, in response to consuming calories, your body begins to use more calories. This is because food needs to be broken down, digested, absorbed and transported to various places in the body for storage. All of these processes require energy.



Although some of the energy generated by your body is used up in the digestion of your food, there is also heat produced each time you eat. This is known as diet-induced thermogenesis (DIT), or the thermic effect of food, and is defined as the amount of energy expenditure, above the basal metabolic rate, that is due to the cost of processing food for use and storage. A common estimate is that around 10 percent of the calories you consume in food will be used up in the processing of that same food.



Interestingly, previous studies by Dr. Yuka Hamada and Professor Naoyuki Hayashi from Waseda University have shown that eating slowly and chewing food thoroughly further increase the energy expenditure associated with the processing of food, as well as stimulating intestinal motility – all of which increases heat generation in the body after food intake. These findings have relevance for people wishing to maintain their weight or, indeed, to lose weight.&nbsp;



However, the findings of these earlier studies were complicated by the fact that the influence of the size of the bolus (swallowed lump of food) and the “lumpiness” of the food were not taken into consideration.&nbsp;



“We were unsure whether the size of the food bolus that entered the digestive tract contributed to the increase in DIT observed after slow eating," explained Professor Hayashi. "Also, do oral stimuli generated during prolonged chewing of food play any role in increasing DIT? To define slow chewing as an effective and scientific weight management strategy, we needed to look deeper into these aspects.”



In their recent study, published in the journal <a href="https://www.nature.com/srep/">Scientific Reports</a>, the scientists designed new experiments that excluded the effect of the food bolus by using liquid food. Their aim was to find out whether oral stimuli generated during prolonged chewing of food had any influence on the increase in metabolic rate that follows the ingestion of food.



The study involved 11 adult male volunteers, each of whom went through three eating trials while various aspects of their physiology, metabolic rate and circulatory systems were monitored.&nbsp;



In the first trial, volunteers swallowed 20ml of cocoa-flavored liquid food every 30 seconds until 200 ml had been ingested. In the second trial, conducted at least three days later, the volunteers were again given 20 ml samples of the same liquid food every 30 seconds but had to keep it in the mouth for 30 seconds before swallowing it. This meant that they tasted the food for 30 seconds each time.&nbsp;



In the final trial, the effect of both tasting and chewing were assessed. In this third test, conducted after another break of at least three days, the volunteers had to “chew” each sample of liquid food for 30 seconds (at a rate of one chew per second) before ingesting. In each trial, a total of 200 ml of liquid food was swallowed and the effects on variables such as DIT, hunger, fullness, gaseous exchange and circulation were measured.&nbsp;



The results showed that several metabolic and physiological measures were significantly affected by prolonged tasting and chewing of food. In particular, DIT increased significantly when food was tasted and when it was chewed for prolonged periods. 



In addition, circulation in the celiac artery increased with taste stimulation and with chewing. This artery supplies blood to the liver, stomach, abdominal esophagus, spleen, and the superior halves of the duodenum and the pancreas, and so the motility of the upper gastrointestinal tract was increased by taste and chewing.&nbsp;



“We found DIT or energy production increased after consuming a meal, and it increased with the duration of each taste stimulation and the duration of chewing. This means irrespective of the influence of the food bolus, oral stimuli, corresponding to the duration of tasting food in the mouth and the duration of chewing, increased DIT.”&nbsp;



The results also showed that protein oxidation was significantly greater in the chewing trial than in the control trial, at 45–60&nbsp;minutes after the test drink. This indicates that chewing helps to speed up and increase the digestion of proteins in particular. Fat and carbohydrate oxidation did not differ significantly between the trials.&nbsp;



The researchers calculated the increase in energy production due to DIT from the 200-kcal beverage used in these experiments. They found that tasting increased DIT from 3.4&nbsp;kcal to 5.6&nbsp;kcal over 90&nbsp;minutes, and adding chewing increased it to 7.4&nbsp;kcal over 90&nbsp;minutes. Thus, the increase in DIT by chewing was between 1.8 and 4.0&nbsp;kcal over 90&nbsp;minutes. The use of liquid reduces the chewing stimulation, resulting in a smaller DIT than was recorded in previous studies that used solid foods.&nbsp;



“While the difference in energy expenditure per meal is small, the cumulative effect gathered during multiple meals, taken over every day and 365 days a year, is substantial," concluded Hayashi.



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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

Chewing food thoroughly may help manage weight

A new study from Waseda University reveals that eating slowly...

In our contemporary society, seven or eight hours of rest per night without any interruptions is considered the norm for a healthy sleeping pattern. However, according to Roger Ekirch, a professor of history at <a href="https://vt.edu/">Virginia Polytechnic Institute and State University</a> (Virginia Tech), sleep is not a biological constant, and changes substantially in different historical and cultural contexts.&nbsp;



While researching nocturnal life in preindustrial Europe and America, Professor Ekirch discovered strong evidence that people used to sleep in segments – a first and a second period of rest, separated by a few hours dedicated to activities such as sex, eating, chatting, praying, or taking medicine. The practice of sleeping throughout the entire night didn’t appear to take hold until a few centuries later, when electricity and the Industrial Revolution changed our <a href="https://www.earth.com/news/ocean-acidification-disrupts-the-behavior-of-fish-shoals/">behavior</a> patterns forever.



The remnants of the “by-phasic sleep” mentioned in many medieval diaries, medical texts, literary works, and prayer books, can be found in our modern society too. “A large number of people who today suffer from middle-of-the-night insomnia, the primary sleep disorder in the United States - and I dare say in most industrialized countries - rather than experiencing a quote unquote, disorder, are in fact, experiencing a very powerful remnant, or echo of this earlier pattern of sleep," explained Ekirch.



However, this does not mean that we should consider by-phasic sleep as “normal” or healthier than other types of sleep. "There is no such thing as natural sleep. Sleep has always been cultural, social and ideological," said Brigitte Steger, a senior lecturer in Japanese Studies at the <a href="https://www.cam.ac.uk/">University of Cambridge</a>.



Moreover, it would be too simplistic to understand the Industrial Revolution as a clear turning point, completely changing sleep patterns.&nbsp;



"There is not such a clear-cut difference between premodern (or pre-industrial) and modern sleep habits," explained Professor Steger. "And sleep habits throughout pre-industrial times and throughout the world have always changed. And, of course, there has always been social diversity, and sleep habits have been very different at court than for peasants, for instance."



Other scholars such as Gerrit Verhoeven, an assistant professor of Cultural Heritage and History at the <a href="https://www.uantwerpen.be/en/">University of Antwerp</a> in Belgium, did not find evidence of fundamental changes in sleep patterns throughout history.



“As a historian I'm concerned that arguments about alleged sleeping patterns in the past - prolonged, by-phasic and with napping during the day - are sometimes presented as a possible remedy for our modern sleeping disorders. Before drawing such conclusions, we have to do much more research about these early modern sleeping patterns," he said.&nbsp;



Professor Ekirch’s findings are explained in great detail in his book <a href="https://www.amazon.com/At-Days-Close-Night-Times/dp/0393329011">At Day’s Close: Night in Times Past</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

Sleeping patterns were different during the Middle Ages

In our contemporary society, seven or eight hours of rest...

New research led by a team of biologists from the <a href="https://www.utah.edu/">University of Utah</a> has found that California mice eat <a href="https://www.earth.com/news/how-predators-have-outsmarted-monarch-butterflies/">monarch butterflies</a> that fall to the ground. This is despite the fact that these butterflies possess a potent “chemical armor” from eating milkweed with toxic cardenolides. The milkweed toxins build up in their bodies and make monarchs unpalatable to most (but not all) predators.



Scientists have long observed that in Central Mexico, the place with the largest winter aggregations of monarchs, the black-eared mouse (Peromyscus melanotis) eats up to 40 of these butterflies each night. More recently, researchers found that the western harvest mouse (Reithrodontomys megalotis) also consume grounded monarchs at the Pismo State Beach Monarch Butterfly Grove in California.



To study mice-monarch interactions, the researchers first trapped rodents in the grove in February 2020 and screened their feces for monarch DNA, which they found in one sample. The scientists intended to return the next year, but unfortunately, after years of gradual decline, the monarch population finally crashed.



"At a site where 100,000 butterflies used to roost, in 2020 there where were fewer than 200 monarchs. So, we had to change tactics," said study lead author Sara Weinstein, a postdoctoral researcher at the University of Utah. "We tested whether rodents would feed on the butterflies using captive-reared monarchs."



Weinstein and her colleagues found that rodents that were offered monarchs ate them, usually favoring high-calorie parts with fewer toxins such as the abdomen or thorax. "Many rodent species are likely to have some resistance to cardenolides in monarchs, due to genetic changes at the site where these toxins bind," explained Dr. Weinstein.&nbsp;



"The Pismo Grove is one of hundreds of western monarch aggregation sites, and it seems likely that, at least in the past, rodents throughout the western monarch range may have supplemented their winter diets with monarchs. If you can handle the cardenolides in a monarch, their bodies are full of fat and offer a pretty good meal."



The massive decline of monarch populations is only one example of an ongoing “insect <a href="https://www.earth.com/news/the-sixth-mass-extinction-is-currently-in-progress/">apocalypse</a>.” According to Dr. Weinstein, about 40 percent of invertebrate species are currently threatened and over 70 percent of flying insect biomass may already be gone. “This is devastating on its own and is also going to have enormous impacts on the other organisms that feed on insects," Dr. Weinstein said.



"Western monarchs and other western butterflies need conservation attention and part of that awareness-raising is illuminating the many ways these animals are interconnected to other insects, birds, mammals, as well as our human communities. This study helps us appreciate more deeply how fewer butterflies means less food for other native animals," added Emma Pelton, a senior conservation biologist at the <a href="https://www.xerces.org/">Xerces Society for Invertebrate Conservation</a>.&nbsp;



The study is published in the journal <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3607">Ecology</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

California mice can feed on poisonous monarch butterflies

New research led by a team of biologists from the...

The evolution of our <a href="https://www.earth.com/news/dozens-of-free-floating-planets-found-in-the-milky-way/">planet</a> is a story of gradual cooling. While 4.5 billion years ago, extreme temperatures and a deep ocean of magma prevailed on the surface of the Earth, the planet’s surface shifted to a cooling phase over the next millions of years that formed a brittle crust. However, the immense thermal energy emanating from the Earth’s core set various dynamic processes in motion, such as plate tectonics, volcanism, and mantle convection.



There is still no scientific consensus regarding how fast the Earth has cooled, or how long it will take until the heat-related dynamic processes mentioned above will stop due to cooling. By investigating the thermal conductivity of the minerals which form the boundary between the Earth’s core and mantle, a research team led by <a href="https://ethz.ch/en.html">ETH Zürich</a> has found that the Earth may in fact be cooling much faster than initially estimated.



Studying this boundary layer, formed mainly of a mineral called bridgmanite, is important since it is the place where the viscous rock of the Earth’s mantle is in direct contact with the hot iron-nickel melt of its outer core, causing significant heat flow.



The scientists used a recently developed optical absorption measurement system in a diamond unit heated with a pulse laser in order to measure the thermal conductivity of bridgmanite in the laboratory, under the pressure and temperatures prevailing inside the Earth.



“This measurement system let us show that the thermal conductivity of bridgmanite is about 1.5 times higher than assumed,” reported study lead author Motohiko Murakami, a specialist in Earth Sciences at ETH Zürich. This finding suggests that the heat flow from the Earth’s core into the mantle is higher than estimated, a phenomenon which increases mantle convection and accelerates the cooling of the Earth.



Moreover, Murakami and his colleagues also discovered that rapid cooling of the mantle will turn bridgmanite into the mineral post-perovskite which, once predominant, will further accelerate the cooling of the mantle due to its higher efficiency in conducting heat.



“Our results could give us a new perspective on the evolution of the Earth’s dynamics. They suggest that Earth, like the other rocky planets Mercury and Mars, is cooling and becoming inactive much faster than expected,” Murakami explained.



Further research is needed to find out how long it will take for convection currents in the mantle to stop. &nbsp;“We still don’t know enough about these kinds of events to pin down their timing,” concluded Murakami.



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S0012821X21005859?via%3Dihub#!">Earth and Planetary Science Letters</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

Earth’s interior is cooling faster than previously thought

The evolution of our planet is a story of gradual...

After rising more than twentyfold in December due to the spread of the highly-contagious <a href="https://www.earth.com/news/did-the-omicron-variant-jump-to-humans-from-mice/">Omicron</a> variant, the number of <a href="https://www.earth.com/news/covid-19-can-prompt-the-creation-of-self-attacking-antibodies/">Covid-19</a> cases in New York City appears to start flattening. In other major cities first hit by the Omicron wave, such as Washington D.C., Newark, Cleveland, New Jersey, Maryland and Boston, case numbers have already started to decrease. The news offers hope to Americans that the Omicron wave may have started to peak and the infections will soon drop rapidly.



This pattern of fast rise and fall of Omicron cases was already noticed a few weeks ago in the case of the variant’s first epicenter, <a href="https://www.washingtonpost.com/world/2021/12/31/south-africa-omicron-coronavirus-peak/">South Africa</a>, and more recently in other countries such as the <a href="https://www.wsj.com/articles/omicron-peak-appears-to-have-passed-in-u-k-offering-hope-the-wave-is-receding-11642078349">United Kingdom.</a> The decline in hospitalizations and deaths in South Africa and the current flattening of the number of severe cases in certain European countries increases hope that Omicron’s toll may turn out to be less than Delta’s.



However, the situation in the United States appears more worrisome than in these other countries. With hospitalization numbers reaching all-time <a href="https://www.reuters.com/world/us/us-breaks-covid-19-hospitalization-record-omicron-surges-2022-01-10/">records</a> and deaths averaging over 1,800 per day in the past week (a 50 percent increase over the past&nbsp; two weeks), the U.S. is “very far from being out if the woods,” as Dr. Bruce Vanderhoff, the director of the <a href="https://odh.ohio.gov/wps/portal/gov/odh/home">Ohio Department of Health</a>, put it.&nbsp;



“If we’ve learned one thing about Covid it’s that it is extraordinarily unpredictable. And things can change dramatically and quickly,” he added.



Even if U.S.’s new case numbers have already peaked and the country will follow the same pattern of rapid descent as places where the Omicron wave has already peaked and is now falling sharply, rises in hospitalizations and deaths are still expected for a few more weeks, possibly even until mid-February. Moreover, U.S.’s rather low vaccine uptake (63 percent) leaves a large part of the population susceptible to more severe forms of illness.



However, the hope that Omicron may be a <a href="https://www.nytimes.com/2022/01/14/world/europe/uk-omicron-coronavirus-pandemic.html">turning point</a> in the pandemic - by offering a large amount of herd immunity at a bearable cost, due to high transmissibility but inherent mildness - increases in many places all over the world, with several countries in Europe starting to treat the variant more like the common flu, and let it become an inescapable, yet less dangerous part of our daily lives.



“At some point, we’ll be able to draw a line — and Omicron may be that point — where we transition from what is a catastrophic global threat to something that’s a much more manageable disease,” said Lauren Ancel Meyers, a professor of Integrative Biology and Statistics at the <a href="https://www.utexas.edu/">University of Texas</a>.



Yet, many public health experts are warning that it is too early to make this call. In a recent plea published in the <a href="https://www.bmj.com/content/376/bmj.o90">British Medical Journal</a>, an international team of scientists argued that there is still an urgent need to “reduce infections to avoid overwhelming health systems and protect public life and the economy.”



“Even under the most optimistic assumptions, letting Omicron run unfettered risks potentially devastating consequences,” they warned.



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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

Omicron is starting to peak in the United States

After rising more than twentyfold in December due to the...

A new study led by the <a href="https://higgs.ph.ed.ac.uk/">Higgs Center for Theoretical Physics</a> in the United Kingdom has found that bacteria may have traveled from <a href="https://www.earth.com/news/scientists-shed-new-light-on-the-origins-of-life-on-earth/">Earth</a> into space after being blown into the atmosphere by high-speed vertical winds. The scientists estimate that particles the size of bacteria can be pushed at least 90 miles into the atmosphere by strong winds, and then carried further by hyper-fast space dust.&nbsp;



Researchers had previously estimated that the biosphere (the area of the Earth containing life) extends up to only 50 miles, but recent discoveries of terrestrial bacteria on the <a href="https://www.nasa.gov/mission_pages/station/main/index.html">International Space Station</a> (ISS) show that life can be found even 250 miles above the Earth’s surface.&nbsp;



According to study lead author Arjun Berera, a researcher at the Higgs Center, vertical winds blowing at up to 335 miles per hour, especially during geomagnetic storms near the poles, could have transported these bacteria into outer space.



“The cases in our paper did not show particles could reach quite as high at 150 km [90 miles], but we think it presents plausible evidence that this is possible, but more data and understanding of vertical winds is still needed,” said Professor Berera.



“Our estimates using reported observations of large vertical winds show that it is conceivable for such particles to be projected from near the highest measured altitudes in the mesosphere up to 120 km,” the study authors added. At this point, the particles have “enough momentum to facilitate the planetary escape.”



According to the scientists, these phenomena could help seed life on other planets, such as Mars. “If a biological particle escaped Earth and it landed on something that was conducive to life, biology tends to grow quite easily. Even if the probability of an escape event happening is quite low, like once every 50 years, if you think about long geological timescales there are a lot of events of potential life transfer that could happen from this mechanism,” explained Berera.



Moreover, these findings could also suggest that life on Earth may have originated through transfer of microorganisms from other planets (the so-called “<a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/panspermia">panspermia theory</a>”). &nbsp;“It is possible if there were say biological particles in early Mars, that they may have been propelled into space and possibly landed on Earth,” Berera said.&nbsp;



Further research is needed to understand what distances can micro-organism travel through space, and what are the factors that influence their journey.



The study is published in the journal <a href="https://royalsocietypublishing.org/doi/10.1098/rspa.2021.0626">Proceedings of the Royal Society A</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

Life on Earth may have blown in from outer space

A new study led by the Higgs Center for Theoretical...

During the last year, people spent an average of 4.8 hours per day on their smartphones, thus nearly a third of their waking hours. Globally, consumers spent 3.8 trillion hours on mobile phones, paid $320,000 on apps every minute, and downloaded over 435,000 <a href="https://www.earth.com/news/health-exercise-apps-teens/">apps</a> per minute. These statistics are detailed in a new <a href="https://www.appannie.com/en/insights/market-data/state-of-mobile-2022/">report</a> from <a href="https://www.appannie.com/en/">App Annie</a>, the “State of Mobile in 2022."



By analyzing a vast amount of data, including downloads, consumer spending, and usage estimates, the App Annie company - a leading global provider of mobile data and analytics - has found that smartphones may be the leading technology of the present.



“Mobile is the greatest of all time and the go-to device of the future,' said Theodore Krantz, CEO of App Annie. “The big screen is slowly dying as mobile continues to break records in virtually every category – time spent, downloads and revenue.”



“Despite access to bigger screens, consumers are still watching content on mobile. Competition is heating up in the space and exclusive content is a way of drawing in new viewers.”&nbsp;



The data revealed that, globally, consumers spent $170 billion on apps (up to 19 percent from 2020), while app downloads have continued increasing at five percent each year, reaching a record of 230 billion in 2021. 



The greatest increases were seen in consumer spending on dating apps ($4.2 billion, marking a 55 percent increase from 2019), followed closely by food and drink apps, with a 50 percent yearly increase. Online advertising is also surging, topping $295 billion in 2021 (a 23 percent increase), and heading toward $350 billion within a year.&nbsp;



In terms of user engagement, TikTok, a newly established Chinese social media app, was the standout winner, ahead of previous leaders such as Facebook, Instagram, or WhatsApp. While TikTok and Facebook both registered 19.6 average monthly hours per user in 2021, TikTok witnessed an extraordinary growth, from only 13.3 average monthly hours in 2020.



“2021 was another blockbuster year in mobile, following a pandemic-induced catalyst to mobile habits in 2020. 2022 is set to blow past records in a transformed economy reliant on digital socialization, hybrid work, and entertainment from the palm of your hand. A mobile-first strategy is a prerequisite for success in our transformed economy,” App Annie said.



However, whether we should be as optimistic as this company regarding such life-changing transformations remains an open question. Research into smartphone technology should also take into account their negative impacts, such as the diminished need for real-life interaction, disruption of sleeping patterns, and the emergence or exacerbation of mental disorders, such as ADHD, depression, or anxiety.



&nbsp;---



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

People spend nearly 5 hours a day on smartphones

During the last year, people spent an average of 4.8...

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

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

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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

Detecting mercury contamination with the tap of a finger

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

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



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



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



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



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



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



Video/ Image Credit: European Space Agency&nbsp;



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



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

Kainji Lake in north central Nigeria

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



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



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



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



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



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



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



Video Credit: Amanda Nguyen/University of Illinois



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



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

Designing crops that can beat the heat

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

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



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



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



Video Credit: ACS Reactions



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



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

How does salt makes things taste better?

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



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



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



Video/ Image Credit: ESA



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



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

Santiago, Chile in South America

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

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



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



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



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



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



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



Video Credit: Johns Hopkins&nbsp;



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



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

Interactive map of the universe includes 200,000 galaxies

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

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



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



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



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



Video Credit: NASA Goddard&nbsp;



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



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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

[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...

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



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



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



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



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



Video Credit: Stowers Institute for Medical Research&nbsp;



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



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

How the immune system responds to injury

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

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



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



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



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



Video/ Image Credit: NASA Goddard



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



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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"

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

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



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



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



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



Video Credit: NASA Goddard&nbsp;



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



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

Satellites reveal how Earth's systems are interconnected

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

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



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



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



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



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



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



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



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

Tiger sharks are shifting poleward as temperatures rise

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