Octopuses have long fascinated scientists with their intelligence, camouflage abilities, and unique biology. 



These remarkable creatures continue to surprise researchers, revealing new secrets about their evolutionary past. One of the most intriguing mysteries has been the question of how octopuses determine their sex.



Scientists at the University of Oregon recently identified a sex chromosome in the California two-spot octopus. This discovery confirms that cephalopods, a group that includes squid and nautiluses, rely on chromosomes for sex determination. 



The research also suggests that this chromosome has existed for at least 480 million years, making it one of the oldest known sex chromosomes in the <a href="https://www.earth.com/news/turquets-octopus-dna-tells-scientists-that-west-antarctic-ice-sheet-collapse-is-close/" target="_blank" rel="noreferrer noopener">animal kingdom</a>.



<h2 class="wp-block-heading" id="h-sex-chromosome-in-octopuses">Sex chromosome in octopuses</h2>



“Cephalopods are already such interesting creatures, and there are so many things we’re still learning about them, especially in neuroscience,” said Gabby Coffing, a doctoral student at the <a href="https://www.uoregon.edu" target="_blank" rel="noreferrer noopener">University of Oregon</a>. 



“This is just showing one more interesting thing about them: They have really ancient sex chromosomes.”



The findings, published in the journal Current Biology, provide new insights into the genetic history of octopuses and their relatives. Understanding this ancient sex determination system could help scientists uncover more about how these intelligent <a href="https://www.earth.com/news/world-octopus-day-the-intelligent-creatures-of-the-sea/" target="_blank" rel="noreferrer noopener">creatures</a> evolved.



<h2 class="wp-block-heading" id="h-sex-determination-varies-across-species">Sex determination varies across species</h2>



Sex determination is not the same for all animals. While humans and most mammals rely on the X/Y chromosome system, other species follow different methods. 



In turtles, sex depends on the temperature at which the eggs incubate. Some fish determine sex using a single gene rather than a whole chromosome. 



Even in humans, sex chromosomes are not always straightforward. Gene mutations or extra sex chromosomes can lead to biological variations that do not fit into a simple male or female category.



Cephalopods have long posed a challenge for genetic research. They are not standard laboratory animals like mice or fruit flies, making it difficult for scientists to study their genetics in depth. 



Although researchers have sequenced the genomes of some octopus <a href="https://www.earth.com/news/octopus-suckers-the-future-of-underwater-adhesives/" target="_blank" rel="noreferrer noopener">species</a>, they still struggle to link specific genes to particular traits. The discovery of an octopus sex chromosome marks a major breakthrough in understanding how these animals develop and reproduce.



<h2 class="wp-block-heading" id="h-unique-sex-chromosome-in-female-octopuses">Unique sex chromosome in female octopuses</h2>



The research team at the University of Oregon made an unexpected discovery when sequencing the DNA of a female California two-spot octopus. 



Among its 30 chromosomes, one stood out because it contained only half the usual amount of genetic material. This anomaly had not appeared in previous studies of male octopus DNA.



“This particular chromosome had half the amount of sequencing data, which indicated there was only one copy,” Coffing explained. “Then as we explored that more, we reached the conclusion that we must have stumbled upon a sex chromosome.”



This finding suggested that female octopuses carry a unique chromosome that males do not. The scientists needed to confirm their discovery by comparing it with data from other cephalopods. 



If this chromosome appeared in multiple species, it would indicate an ancient and consistent pattern of sex determination.



<h2 class="wp-block-heading" id="h-sex-chromosome-exists-in-other-cephalopods">Sex chromosome exists in other cephalopods</h2>



The team analyzed genomic data from other octopus species and found similar evidence of this unique chromosome. 



The experts also detected the sex chromosome in squid, a species that diverged from octopuses between 248 and 455 million years ago. More surprisingly, they identified traces of it in the nautilus, a mollusk that split from the octopus lineage approximately 480 million years ago.



“This indicates that their common ancestor had this similar sex determination system,” Coffing said.



Most sex chromosomes change rapidly over time because they play a crucial role in reproduction. However, this cephalopod sex chromosome appears to have remained stable for hundreds of millions of years. 



This suggests that octopuses and their relatives have relied on this system without significant evolutionary changes.



<h2 class="wp-block-heading" id="h-comparing-ancient-sex-chromosomes">Comparing ancient sex chromosomes</h2>



While the octopus sex chromosome is one of the oldest known, other ancient sex chromosomes exist in nature. 



Some plants, like mosses and liverworts, evolved their sex chromosomes early in Earth’s history. Insects also have sex chromosomes that date back about 450 million years, though these have changed considerably over time.



The discovery in octopuses challenges the idea that sex chromosomes always evolve quickly. It suggests that some systems remain stable if they continue to work effectively over long periods. Cephalopods seem to have found a genetic formula for sex determination that has stood the test of time.



<h2 class="wp-block-heading" id="h-mystery-of-the-missing-w-chromosome">Mystery of the missing W chromosome</h2>



One question remains unanswered: how exactly does the sex determination system work in octopuses? Scientists initially suspected that octopuses might have a system similar to birds and butterflies, where males have two identical chromosomes (ZZ) and females have one of each (ZW).



Kern and his team searched for a W chromosome in female octopuses but didn't find one. This leaves open the possibility that octopuses follow a different system in which males have two copies of a single chromosome (ZZ), while females have only one (Z).



Researchers still need more evidence to confirm how octopus sex chromosomes function. While this study has solved one piece of the puzzle, many questions remain.



<h2 class="wp-block-heading" id="h-secrets-of-the-octopus">Secrets of the octopus </h2>



Octopuses continue to be one of the most enigmatic creatures in the ocean. Their <a href="https://www.earth.com/news/the-octopus-has-mastered-the-art-of-multispecies-hunting/" target="_blank" rel="noreferrer noopener">intelligence</a>, problem-solving skills, and unique genetics set them apart from most other animals. 



The discovery of an ancient sex chromosome adds another layer to their <a href="https://www.earth.com/news/what-animal-will-replace-humans-as-earths-dominant-species-this-scientist-has-an-idea/" target="_blank" rel="noreferrer noopener">evolutionary story</a>. For now, researchers know that this octopus sex chromosome has been around for nearly half a billion years. However, the exact mechanics of how it works remain uncertain.



As scientists continue to explore cephalopod genetics, they will uncover more about how these fascinating animals developed their extraordinary traits.



The octopus has revealed one of its secrets, but it still holds on to many more.



The study is published in the journal <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(25)00005-3" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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Sex chromosome discovered in octopuses is 480 million years old

Octopuses have long fascinated scientists with their intelligence, camouflage abilities, and unique biology. These remarkable creatures continue to surprise researchers, revealing new secrets about their evolutionary past. One of the most intriguing mysteries has been the question of how octopuses determine their sex. Scientists at the University of Oregon recently identified a sex chromosome in the California two-spot octopus. This discovery confirms that cephalopods, a group that includes squid and nautiluses, rely on chromosomes for sex determination. The research also suggests that this chromosome has existed for...

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.

--

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...

<a href="http://www.earth.com/news/human-activity-mammal-extinction/">Extinction</a> can be a difficult thing to verify.  It’s impossible to say with certainty when the last individual of an animal, plant or fungi dies.  There could always be one left hiding somewhere. 

The Ivory Billed Woodpecker (Campephilus principalis) is a good example of an animal that long lingered in uncertainty within the scientific community.  The woodpecker was one of the largest in the world, occupying forests of the American southeast and as a separate subspecies, Cuba.  Habitat destruction in the 1800s made the Ivory Billed Woodpecker incredibly rare and then people stopped reported seeing the bird all together.  For a long time the Ivory Billed Woodpecker was held up as a cautionary tale, as an animal pushed over the brink by human avarice but that’s not necessarily the end of the story.

In 2004, reports came in from Arkansas of an Ivory Billed Woodpecker sighting that was later published in 2005 by a team from the Cornell Lab of Ornithology.  Other reports came in from Florida in 2005, and in January 2017, a scientist with the <a href="https://www.nrl.navy.mil/">Naval Research Laboratory</a> published a report of ten sightings of Ivory Billed Woodpeckers.  Some of these sightings even have photographs and videos with them.  Many of these reports seem fairly substantial but it’s been impossible to verify them and prove the existence of living Ivory Billed Woodpeckers.  C. principalis remains in the no man’s land of ‘probably extinct’ along with plenty of company.

The Bahama nuthatch (Sitta pusilla insularis) has a similar story.  The Bahama nuthatch is a small, but delicately beautiful bird with a long beak and high pitched call.  Sometimes considered a separate species, the Bahama nuthatch is most often considered a distinct subspecies of brown-headed nuthatch.  Either way, the Bahama nuthatch is native to Bahamian pineyards, a subtropical coniferous forest that stretches across four of the Bahamas northern islands.  The nuthatch nests only in mature pine trees of the Bahamian pineyards. 

The Bahamian pineyards are dominated by Bahamian Pine (Pinus caribaea var. bahamensis) but also is abundant with itchy poison wood and small palms among other plants.  I once spent a summer in the pineyards of Abaco Island collecting field data on the Cuban Amazon, or Abaco Parrot (Amazona leucocephala) a bird which may or may not be a distinct species.  The pineyards on Abaco are forests with thin soils over the rocky limestone that makes up much of the Bahamas.  The pineyards seem strange to someone familiar with either more northerly pine forests or tropical hardwood forests, what makes it interesting is that it has features of both.  

Because the Bahamian pineyards are unique and distributed to only a handful of relatively small islands, it makes anything that lives solely in them rare.  Thus, the Bahamian Nuthatch is naturally rare by evolving in a small environment. Indeed, the Bahama Nuthatch is one of the rarest birds in the western hemisphere.  <a href="https://www.uea.ac.uk/about/-/bird-feared-extinct-rediscovered-in-the-bahamas">East Anglia University</a> reported that there was an estimated population of 1,800 individual birds in 2004.  Only 23 individual birds were found in a survey in 2007.

Populations of the Bahama Nuthatch have probably been on the wane since at least the 1950s due to their habitat being destroyed by logging and tropical storm damage.         

When Hurricane Matthew hit the northern Bahamian Islands in 2016, it hit hard.  <a href="https://www.miamiherald.com/news/nation-world/world/article106579967.html">The Miami Herald</a> reported that the hurricane hit land as a class 4 storm, wreaking havoc with sustained winds over 100 miles per hour.  The hurricane hurt animals as well as people and it was feared that the Bahama Nuthatch was finally killed off by Hurricane Matthew.  

The Cozumel thrasher (Toxostoma guttatum) is another example of how vulnerable small island populations can be vulnerable to being wiped out by hurricanes.  The thrasher, native only to Cozumel, a small Mexican island off the Yucatan peninsula may now be extinct, the final push possibly coming from hurricane damage.    

Recently, an expedition lead by masters students Matthew Gardner and David Pereira from <a href="https://www.uea.ac.uk/">University of East Anglia</a>, collaborating with Birdlife International and the Bahamas National Trust undertook an expedition to find out if any Bahama nuthatches remain.  Another team of researchers led by Zeko McKenzie with the <a href="http://www.ub.edu.bs">University of the Bahamas-North</a> supported by the <a href="https://abcbirds.org/">American Bird Conservancy</a> also started looking for the Bahama nuthatch.  Both teams ended up finding the bird in May of this year.  The researchers from University of East Anglia surveyed more than 700 km of forest on foot and stopped at 464 survey points.  This was one of the most exhaustive research expeditions in the Bahamas to date. 

<a href="https://www.sciencedaily.com/releases/2018/08/180823092033.htm">Science Daily</a> reported that the University of East Anglia team made six sightings of Bahama nuthatches throughout their expedition.  It was impossible for the team to identify the sex of the birds or how many of them there were, especially since only individuals alone were ever seen.  The nuthatch was seen in three distinct parts of an area known as Lucaya Estates on Grand Bahama Island. The other team led by a Bahaman researcher, found two nuthatches together, which is more encouraging.

Unfortunately all that can be said with certainty is that there are at least two Bahama nuthatches in the wild.  Without seeing more than two at a time, researchers could simply be seeing one individual over and over again. <a href="https://www.sciencedaily.com/releases/2018/08/180823092033.htm">Science Daily</a> quotes Matthew Gardner of University of East Anglia:

“During three months of intensive searching we made six Bahama Nuthatch sightings. Our search was extremely thorough but we never saw two birds together, so we had thought there might only be one left in existence… The other team have reported seeing two together so that is promising. However, these findings place the species on the verge of extinction and certainly amongst the world's most critically endangered birds.”

Sadly, the Bahama nuthatch numbers may be so low that nothing can be done to prevent the bird’s eventual extinction.  Researchers aren’t even sure what actions should be taken if the bird’s survival was prioritized, many of the drivers of the nuthatch’s population decline are unknown, especially the last precipitous decline in its population.  The only hope for the Bahama nuthatch may be that there is a population hiding on some other island in the Bahamas, less well surveyed than Grand Bahama. 

--

By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="http://earth.com">Earth.com</a> Contributing Writer

Image Credit: Matthew Gardner, <a href="https://www.uea.ac.uk/">University of East Anglia</a>

The Bahama nuthatch found alive but still critically endangered

Extinction can be a difficult thing to verify.  It’s impossible...

Coral reefs contain vibrant ecosystems of marine species that depend on the corals for food, shelter, and protection. 

Fish who call coral reefs home can provide researchers with an excellent early warning system and potential solutions for reef recovery. 

A recent study of farmerfish in French Polynesia offered hope to coral resilience in the face of climate change because warm ocean waters increase <a href="https://www.earth.com/news/territorial-fish-coral-reef-recovery/">farmerfish aggression</a> which can boost coral growth. 

Now, a new study conducted by researchers from <a href="http://www.lancaster.ac.uk/">Lancaster University</a> and <a href="https://www.coralcoe.org.au/">the ARC Centre of Excellence for Coral Reef Studies</a> found that warm waters have the exact opposite impact on aggressive butterflyfish. 

Butterflyfish are sensitive to reef health, and so observing butterflyfish behavior could forewarn of a bleaching event.

The results were published in the journal Nature Climate Change and reveal that as ocean water temperatures increase, butterflyfish aggression cools down. 

Over a two-year period surrounding a mass bleaching event in 2016, the researchers overserved 5,259 encounters between individuals of 38 different species of butterflyfish. 

The team spent over 600 hours observing butterflyfish across 17 reefs in the central Indo-Pacific in Japan, the Philippines, Indonesia and Christmas Island in the Indian Ocean.

A year following the 2016 bleaching events, butterflyfish populations around the reefs kept their numbers, but their behavior changed drastically. 

“We observed that aggressive behavior had decreased in butterflyfish by an average of two thirds, with the biggest drops observed on reefs where bleaching had killed off the most coral,” said Sally Keith, the leader of the study. “We think this is because the most nutritious coral was also the most susceptible to bleaching, so the fish moved from a well-rounded diet to the equivalent of eating only lettuce leaves - it was only enough to survive rather than to thrive.”

The researchers say that butterflyfish could provide a warning system for reef health and that behavior changes may be an indicator of habitat decline and environmental threats.

“This matters because butterflyfishes are often seen as the ‘canaries of the reef’ due to their strong reliance on coral, they are often the first to suffer after a disturbance event,” said Nathan Sanders, a co-author of the study. 

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Warming waters and coral bleaching alter reef fish behavior

Coral reefs contain vibrant ecosystems of marine species that depend...

Could Fido’s coat color play a role in his health? In the case of chocolate Labs, a new study shows that it might. 

Researchers at the <a href="https://sydney.edu.au/">University of Sydney</a> have analyzed vet records for 33,000 Labrador retrievers of all colors. They found that chocolate Labs have higher rates of ear and skin infections than black and yellow Labs do. 

They also found that chocolate Labs’ lifespans are, on average, 10 percent shorter than their non-chocolate counterparts. Lead author Dr. Paul McGreevy said the researchers were surprised by the findings.

"The relationships between coat color and disease may reflect an inadvertent consequence of breeding certain pigmentations," he said. "Because chocolate color is recessive in dogs, the gene for this color must be present in both parents for their puppies to be chocolate. Breeders targeting this color may therefore be more likely to breed only Labradors carrying the chocolate coat gene. It may be that the resulting reduced gene pool includes a higher proportion of genes conducive to ear and skin conditions."

They found that across the UK, the most common health conditions among chocolate Labs were obesity, ear infections and joint problems. Male dogs who had been neutered were more prone to obesity than other Labs.

"We found that 8.8 percent of UK Labradors are overweight or obese, one of the highest percentages among dog breeds in the VetCompass database," McGreevy said.

The researchers collected their data through the VetCompass Programme, which began in 2007 at the <a href="https://www.rvc.ac.uk/">Royal Veterinary College</a> in London in partnership with the University of Sydney. 

The program is now working to collect data on chocolate Labs and their black and yellow fellows in Australia. VetCompass now works with all of Australia's veterinary schools with support from the <a href="https://www.arc.gov.au/">Australian Research Council</a>.

The study has been published in the open source journal <a href="https://cgejournal.biomedcentral.com/">Canine Genetics and Epidemiology</a>.

Chocolate Labs coat colors could affect health

Could Fido’s coat color play a role in his health?...

Female chimps know which males to avoid to keep their babies from being killed, according to a new study. 

The research expands on previous observation of infanticide among <a href="http://www.earth.com/news/chimps-live-longer/">chimpanzees</a> in the Budongo Forest in Uganda first made over 20 years ago. 

“Watching chimps killing infants is really shocking, and although it's pretty well reported, it's not been entirely clear why they do it,” said Adriana Lowe, the lead author of the study published in the American Journal of Physical Anthropology. 

While there is no firm explanation for this behavior, it’s theorized that a high-ranking male will kills baby chimps in order to increase their chances of fathering young.

This would be especially relevant for a male who rose quickly through the ranks and was surrounded by babies of other males. 

Mating is linked to rank, and researchers from the <a href="https://www.kent.ac.uk/">University of Kent</a> and the <a href="https://www.st-andrews.ac.uk/">University of St. Andrews </a>observed the Budongo group of chimps during an unstable period where a mid-ranking male chimp rapidly rose in rank. 

The researchers found that while this was happening female chimps kept their distance from that male chimp in particular because of the risk he posed to their young. 

Instead, females stayed close to and sought the protection of males they felt held a stable high rank. 

The results show that females are extremely sensitive to changes in their group and know which male chimps are more likely to commit infanticide. 

“The mothers' behaviour in our study supports the hypothesis that it's a strategy by the males to get more mating opportunities,” said Lowe. “Male chimps are often described as great politicians as they use complex alliances to compete for high rank but this shows that the females are just as tuned in to the social environment, watching the males from the side-lines, sensitive to any changes which might put their babies in danger.”

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Female chimps can sense which males pose a threat to their young

Female chimps know which males to avoid to keep their...

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



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



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



Video Credit: ACS Reactions



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



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

How does salt makes things taste better?

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

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



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



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



Video/ Image Credit: ESA



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



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

Santiago, Chile in South America

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

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

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



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



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



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



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



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



Video Credit: Johns Hopkins&nbsp;



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



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

Interactive map of the universe includes 200,000 galaxies

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

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



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



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



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



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



Video Credit: ESA&nbsp;&nbsp;



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



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

Lesotho: Africa's "Kingdom in the Sky"

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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://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"

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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

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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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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> describes why satellite images and measurements of our planet have become "essential to our survival, offering a new outlook of our world."&nbsp;



Rising sea levels pose one of the biggest societal threats associated with climate change. According to ESA, satellite altimeter missions such as Copernicus Sentinel-6 are essential in monitoring global and regional changes in sea level.



"Unbeknown to many, the island of Crete, Greece, plays an important role in the Copernicus satellite altimetry constellation and on an international stage," reports ESA.



"Satellite altimetry data have to be continuously monitored at the ESA’s Permanent Facility for Altimetry Calibration where different techniques have pioneered the use of transponders to provide the best measurements to validate satellite altimeters in space soon after launch."



Dr. Craig Donlon explains that, by understanding planet Earth through satellite measurements, we are able to find evidence of change.&nbsp;



Video Credit: European Space Agency&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

Satellites have become essential to our survival

[sendtonews key="761m2QQvR1-2035772-12187" type="single"] Today’s Video of the Day from the...