Scientists have taken a close look at certain reef fish and found something that no one expected. These underwater inhabitants can shift their jawbones in more ways than just up and down. The fish use a quick jaw twist in order to feed more effectively.



Peter Wainwright from the <a href="https://www.ucdavis.edu" target="_blank" rel="noreferrer noopener">University of California, Davis</a> and his colleagues discovered this unusual trait while studying the <a href="https://www.fishbase.se/summary/zanclus-cornutus" target="_blank" rel="noreferrer noopener">Moorish idol</a> (Zanclus cornutus), a striking species known for its long dorsal fin and bold stripes. 



The experts saw swift sideways motions that differ from the typical jaw movements of most <a href="https://www.earth.com/news/ai-illuminates-fish-interactions-in-coral-reefs/" target="_blank" rel="noreferrer noopener">fish</a> - a finding that might explain how certain fish became successful herbivores.



<h2 class="wp-block-heading" id="h-fish-use-the-jaw-twist-to-feed-better">Fish use the jaw twist to feed better</h2>



High-speed video helped <a href="https://www.pnas.org/doi/10.1073/pnas.2418982122" target="_blank" rel="noreferrer noopener">researchers</a> detect a rapid shifting motion in the mouth region of this coral reef species.



Two-dimensional footage does not capture the complexity of the action, so cameras operating at hundreds of frames per second were crucial for seeing the sideways glide that is rarely seen in vertebrates.



The research team examined the mouth structures using scans and dissections, and spotted the unique anatomical elements that permit the jaws to move in multiple directions without slowing down. "I thought, holy cow, that’s not something we expected!” said Wainwright.



<h2 class="wp-block-heading" id="h-jaw-movement-helps-to-scrape-algae">Jaw movement helps to scrape algae</h2>



This side-to-side movement appears to boost the way in which the <a href="https://www.earth.com/news/reef-fish-populations-are-boosted-by-ocean-connectivity/" target="_blank" rel="noreferrer noopener">fish</a> remove bits of algae from rocks on coral reefs. 



Many reef environments feature hard surfaces where edible plant material clings stubbornly, so efficient techniques for scraping and plucking food may be especially important.



Surgeonfish, which share a close kinship with the Moorish idol, also display a version of this sliding jaw function. This capacity helps them graze on tough patches of algae, which supports their diets and possibly contributes to the dominance of certain fish species in these habitats.



<h2 class="wp-block-heading" id="h-fish-jaw-adaptations-for-targeted-grazing">Fish jaw adaptations for targeted grazing</h2>



These mouth maneuvers seem to offer a quick way to yank food free. Fish that rely on suction feeding typically aim for items drifting in the water, but <a href="https://www.researchgate.net/publication/226413625_The_trophic_status_of_herbivorous_fishes_on_coral_reefs_II_Food_processing_modes_and_trophodynamics" target="_blank" rel="noreferrer noopener">grazing species</a> face different challenges when their meals grow attached to stones or <a href="https://www.earth.com/news/how-coral-reef-fish-survive-in-the-worlds-warmest-waters/" target="_blank" rel="noreferrer noopener">coral</a>.



Lateral jaw movement might allow them to target specific chunks of algae, while leaving the rest of the body steady. 



Staying still in choppy waters can reduce energy waste, so subtle mouth motion alone may make feeding smoother and more successful.



<h2 class="wp-block-heading" id="h-how-fish-feeding-affects-coral-reef-health">How fish feeding affects coral reef health</h2>



By adopting this method, <a href="https://www.pnas.org/doi/10.1073/pnas.0801946105" target="_blank" rel="noreferrer noopener">herbivorous</a> fish may help regulate algal overgrowth. Large algal blooms can sometimes crowd out coral species, so hungry fish that trim back the vegetation are often vital for the health of reefs.



“For Zanclus, this adaptation seems to relate to where they feed,” said Michalis Mihalitsis, now at the <a href="https://www.uog.edu" target="_blank" rel="noreferrer noopener">University of Guam</a>, who worked on the study. His comment highlights the link between physical traits and the specific environmental niches that fish occupy.



<h2 class="wp-block-heading" id="h-fish-evolution-and-the-jaw-twist">Fish evolution and the jaw twist</h2>



Vertebrate <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC7672094/" target="_blank" rel="noreferrer noopener">jaws</a> have undergone countless modifications since the first fish appeared, over 400 million years ago. Each structural shift opens up new dietary options, supporting the rise of new species with unique ways of eating.



Sideways jaw movement is familiar to mammals that chew the cud, such as cows and goats. In fish, this trait is much less common, making its discovery in the Moorish idol and <a href="https://dlnr.hawaii.gov/holomua/surgeonfish/" target="_blank" rel="noreferrer noopener">surgeonfish</a> particularly surprising.



<h2 class="wp-block-heading" id="h-looking-ahead-in-reef-research">Looking ahead in reef research</h2>



Scientists plan to explore whether other families of benthic-feeding fish also possess some degree of sideways jaw rotation. As more species are examined, other hidden techniques that have allowed various fish lineages to flourish could come to light.



Understanding fine-scale feeding approaches can reveal how fish keep reefs in balance. Each specialized adaptation for cropping algae may have influenced which species thrived in these colorful yet competitive underwater neighborhoods.



<h2 class="wp-block-heading" id="h-jaw-adaptations-impact-fish-feeding">Jaw adaptations impact fish feeding</h2>



Researchers are starting to see the big picture of how a single trait may drive broad ecological shifts. A fish that can chomp algae in a quick and strategic manner might help shape community dynamics, protect coral structures, and boost biodiversity.



This mouth movement breakthrough raises questions about what else fish mouths can do. It also shows how delicate mechanical tweaks can transform an animal’s role in its ecosystem.



<h2 class="wp-block-heading" id="h-future-research-on-jaw-structures">Future research on jaw structures</h2>



Future work could involve close analysis of mouth ligaments, muscles, and bone joints across diverse reef species. Pinpointing the underlying genetics might allow scientists to trace how such mobility spread among related fish groups.



New knowledge might spark investigations into how environmental pressures push mouth features to evolve. As climate change affects reef conditions, fish that are able to adapt their feeding methods could prove more resilient, and help preserve vital coastal ecosystems.



<h2 class="wp-block-heading" id="h-fish-jaws-reveal-ecosystem-dynamics">Fish jaws reveal ecosystem dynamics</h2>



Exploring these jaw movements offers a view into the interplay of form and function within marine life. When tiny physical details align with dietary demands, entire ecosystems may shift toward richer variety or greater stability.



Observations of how fish navigate algae-laden surfaces broaden our appreciation of the ties between animals and their habitats. Investigators plan to continue searching for morphological secrets that aid survival in the swirling waters of tropical reefs.



The study is published in <a href="https://www.pnas.org/doi/10.1073/pnas.2418982122" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



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Fish use a 'jaw twist' to access more food on coral reefs

Scientists have taken a close look at certain reef fish and found something that no one expected. These underwater inhabitants can shift their jawbones in more ways than just up and down. The fish use a quick jaw twist in order to feed more effectively. Peter Wainwright from the University of California, Davis and his colleagues discovered this unusual trait while studying the Moorish idol (Zanclus cornutus), a striking species known for its long dorsal fin and bold stripes. The experts saw swift sideways motions that differ...

Researchers at the <a href="https://www.u-tokyo.ac.jp/en/index.html">University of Tokyo</a> have been investigating how animals communicate using chemicals called <a href="http://www.earth.com/news/insecticide-attracts-mosquitoes/">pheromones</a>. The study revealed that a substance found in the tears of juvenile mice causes adult females to reject the sexual advances of males. Because pheromones are highly species specific, this behavior does not necessarily apply to humans.

“If humans can detect anything in tears, we won't use the same pheromone signal or receptor as mice,” explained study lead author Professor Kazushige Touhara. “But we are investigating if species share the basic neurocircuitry of how the brain processes an olfactory signal to affect behavior.”

The pheromone, exocrine gland-secreting peptide 22 (ESP22), is only produced by juvenile mice aged one to three weeks. ESP22 is not airborne or noticeable by scent, but is easily spread around the territory as mothers and young mice wipe tears during grooming.

“It is unlikely that other animals would be affected because pheromones are so species specific,” said Professor Touhara. “The sex-rejecting behavior is an innate instinct, so it's also unlikely that the mice will learn to change their behavior or ignore the artificial pheromone.”

Exposure to ESP22 was found to cause both mothers and virgin female mice to reject male sexual advances. In theory, this would benefit juvenile mice by reducing the number of siblings that will be born to compete for resources.

According to the researchers, the tear pheromone could be used in the future as a type of natural birth control to reduce mouse populations.

“ESP22 is difficult to artificially synthesize, so we want to find a smaller portion of the pheromone molecule that could be added to mouse drinking water,” said Professor Touhara. “This could prevent mice breeding in areas where they are pests.”

The study is published in the journal <a href="https://www.nature.com/ncomms/">Nature Communications</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Pheromones in baby tears cause females to reject sexual advances

Researchers at the University of Tokyo have been investigating how...

According to new research from the <a href="https://www.birmingham.ac.uk/index.aspx">University of Birmingham</a>’s School of Geography, Earth and Environmental Sciences, published in Science, the evolution of major species of fish recognizable today took place in shallow coastal waters, referred to as “fragile near shore environments.”

Researchers from the University, along with colleagues from the <a href="https://www.upenn.edu/">Universities of Pennsylvania</a>, <a href="https://umich.edu/">Michigan</a>, and <a href="https://www.manchester.ac.uk/">Manchester</a>, used fossil records of global primitive fish to obtain their findings. The aim of their study was to figure out what early <a href="http://www.earth.com/news/warming-waters-fish-behavior/">fish</a> species diversification looked like more than 420 million years ago. The team used a “big data” approach by studying 2,700 early fossil records and then used mathematical modelling to theorize the type of habitat from which these fish emerged.

"Most of today's major groups of fishes, from jawless hagfish and lampreys through to sharks and the bony fish we are familiar with make their first appearance during the Ordovician, around 480 million years ago, or shortly thereafter" Dr. Ivan Sansom, senior lecturer in palaeobiology at the University of Birmingham and co-lead author of the study, said. "The big surprise for us was that all of these seem to have started their evolutionary journey in these very shallow waters close to the shoreline."

Thanks to their mobility, fish which developed more flexible bodies moved away from the shoreline, whereas others headed toward fresh water. More rigid fish species lingered in shallower waters due to their limited swimming ability. And some fish species even migrated toward the shore where they eventually evolved into land-dwelling vertebrates.

Researchers also found that many of the fossils they looked at were contained within extremely similar environments, which suggests this specific environment may have been ideal for fish evolution.

Dr. Sansom noted that they aren’t sure what it is exactly about these environments that made them so special, “but we do think they provided evolutionary 'hotspots', responsible for generating this rich diversity,” he said.

The research also suggests that the current threats of climate change, elevated sea levels, over-fishing, and ocean pollution could have severely negative effects on future fish species diversification.

--

By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Image Credit: Nobumichi Tamura

The evolution of modern fish took place in shallow waters

According to new research from the University of Birmingham’s School...

Druck

How evolution repeats itself with stripes and color patterns. Researchers from the <a href="https://www.uni-konstanz.de/en/">University of Konstanz</a> discovered why some species of colorful African cichlid fish have stripes while others don’t.

The study sheds insight on the genetic basis of convergent or repeated evolution, where different biological features will show up repeatedly independent of each other in a species' history. 

In this case, the researcher’s findings help explain what’s driving the repeated <a href="https://www.earth.com/news/evolution-changes/">evolution of stripes</a> for cichlids in African lakes.How evolution repeats itself with stripes and color patterns

The study was published in the journal Science. 

Stripes are common in the animal kingdom and among the thousand or so types of cichlid fish in Africa, there are many different variations of vertical and horizontal stripes and well and distinct color patterns. 

This makes the cichlid an excellent model for studying repeated evolution, according to the researchers.

[caption id="attachment_1861287" align="aligncenter" width="700"]<a href="https://www.earth.com/wp-content/uploads/2018/10/color.jpg"><img class="wp-image-1861287" src="https://www.earth.com/wp-content/uploads/2018/10/color-1024x724.jpg" alt="" width="700" height="495" /></a> Image Copyright: Claudius Kratochwil[/caption]

"They are extremely diverse in terms of social behaviour, body shape, colour pattern, and many other biological aspects, but at the same time certain features repeatedly evolved independently in the different lakes,” said Axel Meyer, the leader of the study. 

The researchers were able to identify the genetic mechanisms responsible for stripes and reconstructed the expression of genes necessary to turn stripes “on” or “off” in different breeds of cichlids using CRISPR, a precise tool for editing genes.

“If we use CRISPR-Cas to remove the gene from the genome of a species without stripes,” said Claudius Kratochwil, the first author of the study. “Then even a ‘stripeless’ fish will suddenly develop stripes, as we showed with a CRISPR-Cas mutant fish. This proves that the stripes gene is the decisive genetic factor.” 

The stripe gene is called agrp2 and is similar to the genes responsible for coloring and patterns in different species as well. 

“In breeding experiments, we can exactly determine on which of the 22 chromosomes, even on which area of the chromosome of the fish, the genetic instruction for stripes is located,” said Kratochwil.

Cichlids' stripes have disappeared and re-emerged over the course of millions of years which is why the fish are so intriguing to researchers. Typically when an evolutionary characteristic is lost, it’s lost forever in favor of new traits that better serve a species. 

The specific stripe gene agrp2 of the cichlid fish makes repeated evolution a possibility. 

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer 

Image Copyright: Claudius Kratochwil

How evolution repeats itself with stripes and color patterns

How evolution repeats itself with stripes and color patterns. Researchers...

How butterflies get their wing colors. The vibrant colors of butterfly wings serve many purposes. They can attract a mate, act as camouflage, or communicate different warnings signals. 

But Heliconius butterflies, a group of colorful species native to Central and South America, use their coloring as a disguise. The distinct yellow or white markings of Heliconius cydno stand out against their muted, black wings. 

Researchers from the <a href="https://www.uchicago.edu/">University of Chicago</a> examined Heliconius cydno butterflies in a new study and discovered that one gene is responsible for these yellow or white markings. 

The researchers then used CRISPR <a href="https://www.earth.com/news/alter-butterfly-wing-patterns/">gene editing technology</a> to turn the gene off and change of the coloring of some H. Cyndo butterflies. 

The study was published in the journal Current Biology.

[caption id="attachment_1861284" align="aligncenter" width="700"]<a href="https://www.earth.com/wp-content/uploads/2018/10/butterflies.jpg"><img class="wp-image-1861284" src="https://www.earth.com/wp-content/uploads/2018/10/butterflies.jpg" alt="" width="700" height="433" /></a> Image Credit: Kat Carlton, UChicago[/caption]

First, the researchers developed a genetic map and sequenced the genome of yellow and white H. cydno butterflies.

A gene called aristaless1 (al1) was discovered to be the switch that determined if a butterfly would have white or yellow markings, and the researchers found that if the switch was turned on, the butterfly markings were white. 

After the researchers found out what caused the white markings, CRISPR was used to turn off the al1 gene in the butterfly embryos where it was switched on, in other words in the butterflies that would have white markings. These butterflies ended up with yellow markings instead. 

“For decades people have been cross-breeding these butterflies, and they knew that this white vs. yellow switch was in one spot in the genome. They just weren't able to trace it to the actions of a single gene,” said Marcus Kronforst, the senior author of the study. “Now with CRISPR we can knock the gene out and see what happens. It turns out the evolutionary innovation here is not one species gaining a pigment, but instead turning on a gene to repress an ancestrally present pigment.” 

The same gene that determines wing color for H. cydno may also play a role in mating preference, because butterflies with the same color markings prefer to mate with each other. 

Future research investigating why the butterflies have this mating preference could yield important evolutionary insights about species diversity within Heliconius butterflies. 

“Whether it was natural selection driving it or it was just chance that these two things are linked, that might be part of the reason why we have such a diverse group of butterflies,” said Kronforst. “When the color and preference for the color are linked together, it causes these things to evolve together very rapidly.”

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

How butterflies get their wing colors

How butterflies get their wing colors. The vibrant colors of...

What do sand crabs and comets have in common? You may be surprised. Researchers recently found a link between the mechanics of a sand crab’s tunnel and the pits that cover your typical comet. 

If you walk on a sandy beach, you might notice an array of holes near the shoreline which are entrances to narrow tunnels burrowed by sand crabs. Sand crabs feed on tiny plankton and can quickly scope out their prey as the waves wash up near the burrows. 

Researchers from <a href="http://en.nagoya-u.ac.jp/">Nagoya University</a> knew that the wet grainy mixture of sand was a key component for sand crab burrows and so conducted a study to better understand how the tunnels kept their strength and stability. 

The study was published in the journal Scientific Reports. 

First, the researchers modeled crab tunnels in a wet mixture of tiny glass beads and water which was meant to replicate the densely packed damp sand near the shoreline. 

The team dug different size holes with varying widths and diameters to test the structural capacity of the burrows. Interestingly, when the researchers pressed on the “sand” above a tunnel, the burrow shrunk. 

However, the larger in diameter a burrow, the less stable it was and more likely to collapse. It was diameter which is dependent on the size of sand granules that determined how strong the tunnel was and the pit that formed after collapse. 

The researchers discovered there was a threshold between a burrow collapsing but not disrupting the soil above and collapsing into a pit. This threshold was anywhere between five centimeters and seven centimeters in diameter. 

Sand crabs burrows are rarely larger than five centimeters which means that the crabs know how big is too big for an unsafe burrow. 

The researchers next looked to comets because many comets are covered in pit structures like those of a collapsed sand burrow. 

It’s been suggested that the origin of these pits on comets is the volatile materials that make up the comet itself, a cohesive mixture of <a href="https://www.earth.com/news/interstellar-ice-grains-life-earth/">ice and solid particles</a>. 

The researchers were able to apply their threshold model to comet pit structures and found that the boundaries were similar as far as the diameters of the holes on the comet and the kind of collapse that followed. 

The results show that tunnel collapse in granular matter is more universal than previously thought and besides explaining cometary pits, the study could also help aid in disaster prevention methods for roads and bridges in the future. 

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Sand crabs and comets have more in common than you may think

What do sand crabs and comets have in common? You...

Humpback whales quiet their songs when they hear shipping noise. Whales may be some of the most vocal of the ocean’s inhabitants and their clicks, whistles, and pulsing calls can be heard for miles because sound travels faster underwater than in the air. 

Researchers are still not sure the purpose of certain whale calls, like the famous whale songs of male humpback whales. But clicks and pulsing calls are used to communicate with fellow pod mates and identify what’s around, according to the <a href="https://oceanservice.noaa.gov/facts/whalesounds.html">National Oceanic and Atmospheric Administration. </a>

Unfortunately, human shipping activity is creating an increase in low-frequency ocean noise which is how baleen whales communicate. 

Researchers from the <a href="http://www.owa1989.com/english">Ogasawara Whale Watching Association</a> and <a href="https://www.global.hokudai.ac.jp/">Hokkaido University</a> conducted a study to examine the impacts of <a href="https://www.earth.com/news/ocean-noise-pollution-fish/">noise pollution</a> from shipping traffic on male humpback whale songs.

The study was published in the journal <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0204112">PLOS ONE. </a>

Two underwater recorders were used to capture the whale songs of humpback whales living around the Ogasawara Islands in Japan. Humpback whales quiet their songs when they hear shipping noise 

The researchers recorded 26 singing whales and shipping traffic activity between February and May of 2017. 

The team observed that after a ship passed, whales nearby reduced their singing or stopped singing altogether for at least 30 minutes before resuming their songs. 

There were also fewer male humpback whales who sang within 500 meters of a shipping lane. 

“Humpback whales seemed to stop singing temporarily rather than modifying sound characteristics of their song under the noise, generated by a passenger-cargo liner,” the authors wrote in their study. “Ceasing vocalization and moving away could be cost-effective adaptations to the fast-moving noise source.” 

The study further highlights the dangers of noise pollution in the ocean as it impacts whale behaviors and can harm marine wildlife.

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer 

Image Credit: Ogasawara Whale Watching Association

Humpback whales quiet their songs when they hear shipping noise

Humpback whales quiet their songs when they hear shipping noise....

Proud pet owners will tell you that their dog or cat is the smartest one around — Spot can even tell time, they say. As ridiculous as that sounds, they might be onto something. According to a recent study from <a href="https://www.northwestern.edu/">Northwestern University</a> published in the journal of Nature Neuroscience, our <a href="http://www.earth.com/news/pets-happier-healthier-wealthier/">pets</a> can actually judge time.

Researchers looked at an animal’s medial entorhinal cortex, the brain’s memory and navigation hub. There, they discovered a set of neurons that work like a clock when an animal is waiting.

Daniel Dombeck, associate professor of neurobiology in Northwestern's Weinberg College of Arts and Sciences and head of the study, said, “This is one of the most convincing experiments to show that animals really do have an explicit representation of time in their brains when they are challenged to measure a time interval."

Dombeck theorized that because the medial entorhinal cortex encodes spatial information in “episodic memories,” it might also be responsible for encoding time, thus helping your pet acknowledge time passing while waiting.

To test this theory, Dombeck and his team constructed a virtual reality course in which a mouse ran on a physical treadmill within a virtual environment. While on the course, the mouse reached a door at the end of the hallway and had to wait six seconds for the door to open and grant the mouse clearance to its reward.

After training the mouse within this course, the team then made the door “invisible.” The mouse was still aware of where the door was, yet no physical door was present. Even so, the mouse waited six seconds before passing through the doorway.

This shows that the mouse unknowingly tapped into the medial entorhinal cortex and relied on time encoding to fully understand the course ahead. What’s more is that when the team studied images of the mouse’s brain by way of two-photon microscopy, they watched two different sets of neurons fire — one while the mouse ran the course and the other when the mouse approached the doorway and waited.

“As the animals run along the track and get to the invisible door, we see the cells firing that control spatial encoding," Dombeck said. "Then, when the animal stops at the door, we see those cells turned off and a new set of cells turn on. This was a big surprise and a new discovery." Dombeck noted that this second set of cells encode how much time an animals has been waiting.

Not only does this result prove our pets can, in fact, tell time to a certain degree, the discovery of time encoding cells could potentially lead to early-detection Alzheimer’s tests and treatments. Who knew a pup’s impatience could lead to such an important medical breakthrough?

--

By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Your pets can indeed tell time, new study shows

Proud pet owners will tell you that their dog or...

O magic sleep! O comfortable bird,
That broodest o’er the troubled sea of the mind
Till it is hush’d and smooth! O unconfin’d
-John Keats, “Endymion”, 1818
Sleep is often considered a cousin of death. If that’s so, what then are <a href="http://www.earth.com/news/plants-hibernate-underground/">hibernation</a>, and its related states, estivation and torpor? Given that these states involve substantially lowered metabolic rates and body temperatures, and frequent insensibility to environmental stimuli, they might be even closer relatives of the eternal slumber. Brothers and sisters, perhaps. 

In fact, though, these evolutionary strategies allow animals in harsh environments to hold onto their mortal coils, not shuffle them off. The mammals, reptiles, amphibians, and invertebrates that undergo these states often live in climates that become extremely hot or extremely cold during portions of the year. 

As such, temperature has long been considered the primary driver of such adaptations, at least in popular depictions. Dormancy is found in both homeothermic animals, which produce their own heat, and ectothermic animals, which rely on external heat sources. Hibernating bears and rodents wait out the winters in warm burrows, subsisting on stored fat (or, in the case of some rodents, stored food that is eaten when they periodically wake up). 

Estivating reptiles, amphibians, and even fish that live in climates with a prolonged dry season retreat underground and enter a quiescent phase until the rains come. Reptiles and amphibians in temperate climates hibernate too, and a few desert mammals estivate. 

While climatic variation is indeed a key driver of dormancy in animals, recent research has suggested that <a href="https://www.uregina.ca/science/biology/people/faculty-research/brigham-mark/files/Geiser_and_Brigham%202012.pdf">other factors may have shaped the evolution of dormancy as well</a>. Parasite loads may be decreased, intraspecific competition may be reduced, water conservation may be increased, energy storage during migration may be enhanced, and reduced food supplies may be better tolerated in animals willing to shelve themselves for a period of time.

This complex array of factors appears to have influenced the habits of the common poorwill (Phalaenoptilus nuttallii), a bird in the order Caprimulgiformes, which comprises the nightjars, whippoorwills, frogmouths, and their relatives. Native to the grasslands, patchy forests, and deserts of western North America, the common poorwill is the only bird known to enter a state resembling hibernation. 

It’s worth noting, though, that some 100 species <a href="https://books.google.com/books?id=WHQFuLZBIC0C&amp;pg=PA8&amp;lpg=PA8&amp;dq=common+poorwill+hibernation&amp;source=bl&amp;ots=W-vyygLDwM&amp;sig=5yzFonlB3GwPhqBQNxhv-rguB9A&amp;hl=en&amp;sa=X&amp;ved=2ahUKEwjZ9pjy3JHeAhWR61MKHe59Bao4MhDoATAAegQICRAB#v=onepage&amp;q=common%20poorwill%20hibernation&amp;f=false">belonging to some 11 orders of bird</a>, among them the Apodiformes (hummingbirds, swifts), Caprimulgiformes, Ciconoiiformes (vultures), Coliformes (colies), Columbiformes (pigeons), Cuculiformes (cuckoos), Falconiformes (falcons), and Passeriformes, are known to enter states of torpor, which is essentially a briefer period of hibernation-like behavior in which metabolism may drop by as much as 90% and body temperature is also substantially lowered. Some do so only seasonally, while others, notably hummingbirds, swifts, and <a href="https://www.une.edu.au/__data/assets/pdf_file/0009/31986/2012-brigham-mcKechnie-doucette-geiser-heterothermy-in20caprimulgid-birds.pdf">many members of the Caprimulgiformes</a>, do so on an almost daily basis. 

This is known as heterothermy; while these animals can produce their own body heat, they can also drop their own temperatures to levels that might seem unlikely to support life. Heterothermy is most common in diurnal birds that rest during the nighttime hours, though the largely nocturnal Caprimulgiformes do so during the day. By lowering their metabolic rates, which may be quite high when they are not torpid, they conserve valuable energy resources.

In the common poorwill, this torpid state verges into an extended period of dormancy that closely resembles the hibernation observed in mammals and other classes of animal. The Hopi Native Americans called it Hölchoko, the sleeping one. 

This was first documented in 1946 by Edmund Jaeger in the Colorado Desert of California. The common poorwill enters a state of torpor that lasts up to 86 days, per Jaeger’s research. Unlike most other hibernating animals, the poorwill enters its state of suspended animation in relatively exposed areas. Jaeger first noticed a hibernating poorwill in a crack on a cliff wall. He was able to pick the bird up and he and his students even shouted in a futile attempt to wake it. The dormant bird’s only reaction was to crack an eye. Jaeger popped it back into its crevice and ten days later, when he returned, it was still there, unmoved. The bird’s temperature was measured at 64°F, perhaps 40% lower than that of most birds. It was found in the exact same crevice during three consecutive winters.

The motivations for this adaptation are somewhat more complex than simple variance in climate. Food does appear to be at least one factor, perhaps the dominant one. <a href="https://www.jstor.org/stable/30158263?seq=1#page_scan_tab_contents">In laboratory studies</a>, common poorwills have been induced into torpid states by food deprivation. Because the northernmost populations migrate south and thus overlap with the territories of their southern conspecifics, and those of other migrants, food competition may be particularly intense in the winter. 

In the arid environments that common poorwills inhabit, this is more of a problem than it might be in a fecund tropical jungle swarming with insects year-round. Why not hunker down and wait out the bickering and competition that would be sure to ensue if every poorwill in the area were lunging after the paltry few insects available? So it is that climate, niche, ecosystem, and competition for prey have converged to produce this unique animal.

Indeed, <a href="https://www.researchgate.net/publication/234130809_Ecological_correlates_of_torpor_use_among_five_caprimulgiform_birds">recent research indicates</a> that this may also be the case in related birds that become torpid for less dramatic periods of time. A relative in Africa, the freckled nightjar, inhabits somewhat similarly arid habitat and also appears to enter torpor during suboptimal times, though usually for periods of hours rather than weeks. Research has tied this species’ habits to the lunar cycle and has hypothesized that the low visibility on nights with waning moons detracts from the nightjar’s ability to spot its insect prey. The owlet-nightjar of Australia exhibits similar patterns of torpor, though this had not been tied to the lunar cycle as in its African relatives. 

Interestingly, like hibernating mammals, common poorwills appear to briefly arouse every so often in response to either sun warmth or their own circadian rhythms. Then, after cracking an eye and reassuring themselves that they are still alive, they power down again. And, one assumes, dream of buggier days.

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By <a href="mailto:rtpallardy@gmail.com">Richard Pallardy</a>, <a href="http://earth.com">Earth.com</a> Contributing Writer

Different factors drive varying states of hibernation in animals

O magic sleep! O comfortable bird, That broodest o’er the...

A team of scientists led by the <a href="https://www.exeter.ac.uk/">University of Exeter</a> has found that, like humans, <a href="http://www.earth.com/news/young-birds-teacher/">birds</a> are startled when inanimate objects suddenly move. While testing how jackdaws responded to moving birds, snakes, and moving sticks, the researchers found that the birds were most alarmed by the moving sticks.


Dr. Alison Greggor, formerly of the <a href="https://www.cam.ac.uk/">University of Cambridge</a> and now at the San Diego Zoo Institute for Conservation Research, is the study's lead author.

“Although as humans we see the divide between animate and inanimate objects as an intuitive one, we've had very little evidence that wild animals also see the world this way,” explained Dr. Greggor.

“Laboratory studies have shown that human infants and a few other species discriminate between animate and inanimate objects. This ability is assumed to have evolved to support social interactions, but its role for wild animals has never been examined.”

“Our work extends the potential function of this ability beyond the social realm. It might therefore be a more common ability than previously thought.”

For the investigation, the researchers placed remote-controlled objects in the nests of jackdaws. This allowed the experts to observe how the birds perceived potential threats to their offspring.

The jackdaws were startled by any movement in the nests and produced alarm calls. The longest delays in returning to the nest, however, were noted after the birds saw the remote controlled stick move.

This behavior indicates that jackdaws recognized the movement as being unusual and unexpected. The birds likely delayed re-entering the nest in order to gather more information out of caution.

Dr Alex Thornton, of the Centre for Ecology and Conservation added: “There is still a great deal we do not understand about some of our common bird species. Dedicated field experiments, such as ours, can yield insights into their minds, revealing more about how they understand the world.”

The study is published in the journal <a href="http://rsos.royalsocietypublishing.org/">Royal Society Open Science</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Birds are more alarmed by moving sticks than moving snakes

A team of scientists led by the University of Exeter...

For many species, smell is another form of communication and helps convey social cues. A mother bat, for example, will use scent and listen for special calls to find her pup among <a href="https://news.nationalgeographic.com/2018/05/lesser-long-nosed-tequila-bats-animals-spd/?user.testname=none">large clusters of young. </a>

The right olfactory cue could also help in the search for a mate or be used to determine a group or family member from strangers. 

Most mammals rely on scent to some degree or other, but primates have long been thought to possess a poor sense of smell. 

Very little is understood about how non-human great apes use smell, but a new study conducted by researchers from the <a href="https://www.uni-leipzig.de/en/">University of Leipzig</a>, the <a href="https://www.eva.mpg.de/">Max Planck Institute for Evolutionary Anthropology,</a> and <a href="https://www.dur.ac.uk/">Durham University</a> provides new insight into social odors and their signals for <a href="https://www.earth.com/news/chimps-live-longer/">chimpanzees.</a>

The study, published in the journal Proceedings of the Royal Society B, is the first of its kind. 

“Odor might be especially important because most chimpanzees live in dense forests where visibility is low, and because in chimpanzee societies, group members split up into subgroups that may not see each other for days,” said Stefanie Henkel, the lead author of the study. 

The researchers collected the urine of two groups of chimpanzees and placed samples along with an unscented control in plexiglass boxes. 

This allowed the researchers to monitor the chimpanzee’s response to familiar urine as well the urine from a stranger. 

After being presented with the boxes, the researchers videotaped the chimpanzee’s reaction and found that the most time was spent sniffing the boxes that held actual urine.

“Interestingly, in the vast majority of cases, the first investigatory behavior the chimpanzees showed when they approached a box for the first time was related to olfaction, rather than touch or just visual inspection,” said Henkel. 

The chimpanzees also discriminated between familiar smells and the smells from strangers and spent longer on the boxes that came from the strange group. 

“Chimpanzees are highly territorial, and encounters between groups are mostly hostile - in fact, they sometimes kill individuals from other communities - so olfactory cues might help them to locate other animals and determine whether they are group members or strangers, enhancing their survival and leading to fitness benefit,” said Henkel. 

When it came to familiar smells, the researchers found that a chimpanzee would spend more time investigating a box that held urine that belonged to close relative. 

Like bats that use scent to find their pups, the study provides the first evidence of kin recognition using scent among great-apes. 

“The ability to recognize kin is crucial, because it allows animals to choose appropriate partners for coalitions, avoid mating with close relatives, and avoid killing their own offspring,” said Jo Setchell, a co-author of the study. “Our results help us to understand the evolution of primate chemical communication and suggest that we should pay more attention to olfaction in apes.” 

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer 

Image Credit: Stefanie Henkel

Chimpanzees can tell strangers from family using scent

For many species, smell is another form of communication and...

Since the widespread expansion of humankind, biodiversity has suffered. 

Hunting, habitat loss and degradation, and overexploitation have been some of the main drivers of species loss over the years. 

According to the Living Planet Assessment from the <a href="https://www.zsl.org/">Zoological Society of London</a>, there has been a <a href="https://www.bbc.com/news/science-environment-37775622">58 percent decline in global wildlife populations since 1970</a>, and this number could fall by as much as two-thirds in the next two years. 

Some species that have been particularly hard hit are large herbivores like elephants and rhinos. Once common across the world, large herbivores have been largely replaced by livestock. 

Livestock are some of the biggest emitters of <a href="http://www.earth.com/news/new-cattle-feed-methane-emissions/">methane</a>, a potent greenhouse gas, and as such are major contributors to climate change and atmospheric greenhouse gas levels. 

How do we combat biodiversity loss, livestock emissions, and climate change? Trophic rewilding may be the answer. 

The Philosophical Transactions of the Royal Society B recently published a special issue dedicated to rewilding. 

The <a href="http://rstb.royalsocietypublishing.org/content/373/1761">issue includes 16 papers</a> that discuss the different aspects of rewilding which is considered a modern conservation solution that could help reduce the impacts of climate change and restore large herbivores to their native habitats. 

Rewilding involves restoring habitats and declining animal populations by reinstating the natural ecosystem of an area. 

One main argument for rewilding is that by bringing back large herbivores and reducing our demand for livestock, it will reduce the amount of methane emissions from cattle. 

Native herbivores like elephants and rhinos are thought to have a small methane footprint, according to a <a href="https://www.carbonbrief.org/in-depth-could-rewilding-help-tackle-climate-change">Carbon Brief article. </a>

Joris Cromgist, an author <a href="http://rstb.royalsocietypublishing.org/content/373/1761/20170432">of one of the 16 studies</a>, explained to Carbon Brief that though there is little research on the methane emissions of large herbivores because many large herbivores have different digestive systems, they produce less methane when they graze. 

“Little empirical data is out there for wildlife. The largest emissions, per individual animal, come from large ruminants, such as cattle, and similar wild species, such as African buffalo or American bison,” Cromgist told Carbon Brief. “The least methane is, in principle, produced by the large non-ruminants, such as rhino, elephant, and equid [horse] species.”

Trophic rewilding could also help reduce the <a href="http://rstb.royalsocietypublishing.org/content/373/1761/20170443">severity and frequency of wildfires</a> caused by weather extremes, drought, and habitat loss. 

One study suggests that large vertebrates could help combat fires by eating plant matter that could increase fire risk and limit the spread of dense vegetation. 

Rewilding could provide a crucial lifeline for today’s rapidly declining populations of animals while also tackling the major challenge of climate change. 

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Paid for by <a href="http://earth.com">Earth.com </a>

Trophic rewilding may be an effective tool to fight climate change

Since the widespread expansion of humankind, biodiversity has suffered. Hunting,...

A new study from experts at <a href="https://stockton.edu/">Stockton University</a> has found that the small limbs of Tyrannosaurus rex and other theropods were much more useful than previously realized. The researchers analyzed the arm movement of the American alligator and the domestic turkey - distant relatives of <a href="http://www.earth.com/news/tyrannosaurus-rex-big-run/">T. rex</a> - and discovered that theropods likely had the advantage of extremely flexible limbs.

Study co-researchers Christopher Langel and Matthew Bonnan told <a href="https://www.livescience.com/">Live Science</a> that meat-eating dinosaurs “may have been able to rotate the palm of the hand inward and upward in such a way that the palm would face the chest when the elbow was flexed.”


The specific advantages of this flexibility are unclear, but the researchers said that it may have allowed for theropods to bring their prey in closer.

“We might speculate that such a movement (rotating the forearm and hand in toward the chest) could allow some theropods to bring prey in close for a bite,” the experts told Live Science.

The researchers cannot study the actual arm of a T. rex due to the fact that soft joint tissues rarely fossilize. “As a consequence, we are missing information on what the shapes of the (theropod) joints actually looked like and how far apart the bones were when the predatory dinosaur was alive,” said the researchers.

Instead, the study was focused on the wings and arms of alligator and turkeys, using a technique called X-ray Reconstruction of Moving Morphology (XROMM). The results revealed that turkey and alligator elbows are quite complex.

“It was especially surprising to see how much the forearm bones could rock side to side at the elbow, a movement that is essentially off limits to mammals like us,” Langel and Bonnan said to Live Science. 

“In essence, alligators and turkeys can turn the palm of the hand inward and upward like we do, but by using more-complex movements of the bones at the elbow. Once again, Mother Nature has solved the same problem in different ways.”

The research was presented at the 78th annual Society of Vertebrate Paleontology meeting.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The tiny arms of the T. Rex were more useful than previously thought

A new study from experts at Stockton University has found...

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



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



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



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



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



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



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



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



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



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

Is chocolate the next nutritional powerhouse?

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

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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

Detecting mercury contamination with the tap of a finger

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



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



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



Video Credit: ACS Reactions



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



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

How does salt makes things taste better?

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



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



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



Video/ Image Credit: ESA



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



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

Santiago, Chile in South America

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

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



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



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



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



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



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



Video Credit: Johns Hopkins&nbsp;



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



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

Interactive map of the universe includes 200,000 galaxies

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



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



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



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



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



Video Credit: ESA&nbsp;&nbsp;



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



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

Lesotho: Africa's "Kingdom in the Sky"

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



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



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



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



Video Credit: ESA&nbsp;



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



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

The city of Dublin on Ireland's east coast

[sendtonews key="qjvhBOBnY8-2426650-12187" type="single"] Today's Video of the Day from the...

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



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



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



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



Video/ Image Credit: ESA



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



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

The province of Zaragoza in northeast Spain

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

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



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



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



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



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



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



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



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



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



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



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

The rapid retreat of the Columbia Glacier

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



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



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



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



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



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



Video &amp; Image Credit: ESA



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



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

The Pyrenees Mountains in southwest Europe

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

Earth,Like,Exoplanet,3d,Render

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



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



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



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



Video Credit: NASA Goddard



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



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



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

Two distant planets may be "water worlds"

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

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



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



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



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



Video Credit: NASA Goddard&nbsp;



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



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

Satellites reveal how Earth's systems are interconnected

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

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



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



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



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



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



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



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



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

Tiger sharks are shifting poleward as temperatures rise

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

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



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



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



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



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



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



Video Credit: ESA&nbsp;



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



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

Melt ponds on the Greenland Ice Sheet

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



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



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



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



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



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



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



Video Credit: ESA



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



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

The history of Mars is much more complex than we thought

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



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



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



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



Video Credit: Stowers Institute for Medical Research



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



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

Cavefish are healthy despite their sedentary lifestyle

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



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



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



Video Credit: NASA Earth Observatory&nbsp;



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



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

Satellites capture the world's biggest and fastest waves

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