Curio Cabinet / Nerdy Curio

Would you like to go deep sea diving in deep space? According to a paper published in Icarus by scientists at the Planetary Science Institute, one of the moons of Uranus likely had an ocean that was over 100 miles deep. In comparison, the deepest part of the ocean on Earth is only around seven miles deep, while the average depth is around two miles. Ariel, an ice-covered moon and the fourth-largest of Uranus’s satellites, apparently would have put those figures to shame. It’s especially impressive considering that Ariel is only 720 miles wide. Scientists were able to figure out the moon’s history by looking at its surface, which contains telltale signs of the past. After the surface was fully mapped, the scientists used a computer program to model the tidal stresses that would have been necessary to shape Ariel. These would have fluctuated with the moon’s proximity to Uranus in orbit. The deviation in orbit, or eccentricity, was around 0.04 in the past, or about 40 times the current value. By combining the data on the surface of Ariel as it is today with the eccentricity of the past, scientists were able to determine what the moon’s oceans were once like, though they’re still not sure exactly how long ago they existed. Ariel is the second of Uranus’s moons that was found to have once contained large amounts of water. That’s one more than Neptune, which needs to catch up if it wants to live up to its god-of-the-sea name!

 
[Image description: A vintage, sepia-tone photograph of the moon.] Credit & copyright: The Moon, 1857–60, John Adams Whipple, James Wallace Black. The Metropolitan Museum of Art, Robert O. Dougan Collection, Gift of Warner Communications Inc., 1981. Public Domain.
 

They didn’t sail with Jason to steal the golden fleece, but they still come by their name naturally! Argonauts are the only octopuses on Earth that have shells, albeit thin ones that are mainly used for reproductive purposes. Though they live in tropical and temperate waters all over the world, they aren’t as well known as some of their cephalopod cousins.
 
Argonauts are strange-looking, even by octopus standards. They’re quite small, and their size varies greatly depending on their sex. Females are roughly 20 times larger than males. While females can grow up to 15 inches long, males rarely reach a full inch in length. Only female argonauts have a shell, but they aren’t born with it. They create it themselves by secreting a liquid from their frontmost tentacles which quickly hardens. This shell gives them their nickname, “paper nautiluses”, since it makes them look a bit like their nautilus cousins, but unlike nautiluses, argonaut’s “shells” are not true shells. They don’t have valves that allow for water flow and movement, like nautiluses’, and argonauts can’t tuck themselves fully inside their shells to hide. In fact, argonauts’ shells are so thin that they provide little protection. Instead, female argonauts use them like pouches in which to store their eggs. This is a useful thing for them to do since, unlike most octopuses, argonauts don’t live in deep water. That means that they don’t have access to the seafloor caves that most octopuses lay their eggs in. Near the water’s surface, there aren’t many places to hide eggs, hence their shell solution.
 
Argonauts’ shells serve another important function. They help keep the females afloat, even when they’re burdened with eggs. They do this simply by trapping air, like a lifejacket. Without their shells, female argonauts wouldn’t be able to stay near the water’s surface, which would be a big problem since they can’t survive in colder, deeper waters.
 
Like all octopuses, argonauts are predators, though they’re not fast enough to catch fish the way that larger species do. Instead they feed mainly on mollusks, jellyfish, and salps that drift by in open waters. Their shells may be (somewhat) hard, but that doesn’t mean they have to work hard.

 
[Image description: An illustration of an argonaut octopus, with a brown-spotted body and black beak.] Credit & copyright: Internet Archive, Die Cephalopoden by Carl Chun, 1852-1914. Publisher [Jena], G. Fischer. Published: 1910. Public Domain.

They were handy, but they weren’t exactly apex predators. Homo habilis are thought to be the earliest human species and were once thought to be the first to use tools, hence their name, which means “handy man” in Latin. They were also thought to be the first to reverse the predator-prey relationship, thanks to their tool-making skills. Unfortunately, researchers at the University of Alcalá in Spain have found evidence that they weren’t quite the hunters they were made out to be, according to a paper published in the Annals of the New York Academy of Sciences.
 
Homo habilis lived between 2.4 million and 1.4 million years ago, and their adults ranged between 40 to 53 inches tall and weighed around 70 pounds. Despite their diminutive size, they were long considered to be more predator than prey. However, that belief might need to be reexamined now that researchers have examined Homo habilis remains from Olduvai Gorge in Tanzania dating back two million years. The researchers compared marks found on the remains to 1,496 images of teeth marks from extant carnivores. Using AI to analyze the marks, they found that many of them were left by leopards. The teeth marks seem to strongly indicate that the hominins were being hunted, rather than simply having their remains consumed by scavengers. It must have been a long, long climb up the food chain.

[Image description: A partially-intact homo habilis skull on display at a museum.] Credit & copyright: Daderot, Wikimedia Commons. This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication.
 

If it’s brown…watch it chow down! This week marks the return of Alaska’s Fat Bear Week, a cherished annual tradition in which Alaskans vote, tournament-style, on which local brown bear they think is the fattest. This time of year, Alaskan brown bears gain hundreds of pounds, sometimes doubling their body weight. They aren’t in need of a diet, though. They’ve fattened up after gorging on salmon in preparation for winter hibernation.
 
Brown bears don’t just live in Alaska; they’re also found in other parts of North America, including Canada, Montana, and Wyoming. Even when it isn’t fat bear week, brown bears are pretty enormous. They can be five feet tall when standing on all fours, and up to ten feet tall when standing on their hind legs, which they’re capable of doing with relative ease (though they can’t easily walk on two legs.) Mature, male brown bears can weigh up to 1,500 pounds. Yet, as formidable as brown bears are, they’re not the meat-crazed predators that they’re sometimes portrayed to be. In fact, about 75 percent of their diet consists of plant matter, like wild fruits, berries, and roots. When they do eat meat, they’re not averse to carrion, as their strong digestive systems allow them to break down rotting meat and even bones without issue. Most of the fresh meat they eat comes from fish, especially salmon, which migrate through Alaskan rivers in huge numbers every autumn on their way to spawn.
 
Brown bears endure the harsh Alaskan winters by hibernating, which involves digging and staying in their underground dens for about seven months out of the year. Yes, these bears spend more time hibernating than not. Hibernation is a lot more complicated than regular sleep, though. Bears enter a deep, sluggish state called torpor in which their breathing and heart rate slows, and their body temperature can drop up to 12 degrees. In this state, they don’t eat or drink, surviving off their fat stores instead. If a bear fails to eat enough in the weeks leading up to hibernation, they can easily freeze to death in their dens.
 
Amazingly, brown bears give birth while hibernating, nursing their cubs in their dens until they’re strong enough to go above ground. It may seem like odd timing, but it’s actually ideal, since the cubs leave their dens around springtime, just as food is becoming abundant again. The cubs stay with their mothers for around two and a half years, learning to forage and hunt before striking out on their own. It takes a long time to learn the ins and outs of all that hibernating!

 
[Image description: A mother and baby brown bear touching noses.] Credit & copyright: Lisa Hupp/USFWS. Public Domain.

These now-extinct people are currently making a big impact. According to a paper published in the Journal of Human Evolution by researchers at the University of Pannonia in Hungary, the remnants of Denisovan DNA might be responsible for granting some people immunity against tropical diseases. Denisovans were a group of hominins that emerged around 370,000 years ago, and their classification is still a matter of debate, owing to the limited amount of fossils found. What is known, however, is that genetic traces of Denisovans still remain in modern humans, much like with Neanderthals. Some of those traces are apparently responsible for immunity against certain tropical diseases, like malaria. Researchers came to this conclusion after using a computer model to reconstruct the ancient climates of three regions where Denisovan remains were found: Siberia, the Tibetan Plateau, and Laos. The results of the model were then compared to the habitats of disease carrying insects like mosquitoes and ticks as well as data regarding Denisovan DNA in people today. What they found was that the Denisovans likely lived in all types of environments and were exposed to many diseases that still plague people today. In places where those diseases are more common, more of the Denisovan genome remains. For example, people in Melanesia are more likely to carry HLA-H*02:07, a gene originating from Denisovans that is associated with immunity against some tropical diseases. By comparing extant genes and the diseases they are associated with, researchers can also track the migration of ancient Denisovans. For example, the aforementioned Melanesians only carry the genes related to tropical diseases, not Lyme disease, indicating that they’re not descended from the same Denisovans who lived in Siberia or Tibet and developed a resistance to that disease. Denisovans might be gone, but it seems they may never stop helping us out.

You can ko-a-la us crazy, but we think these are some of the most fascinating animals on the planet. They’re about to get a lot healthier, too: Australia recently approved a koala-specific vaccine to help the species fight chlamydia, a sexually-transmitted disease that around 48 percent of wild koalas are thought to have. The new vaccine reduces mortality by around 65 percent, which is especially good news since koala populations are currently in decline.
 
Koalas, like many animals native to Australia, are marsupials, meaning that they give birth to tiny, underdeveloped young which then attach themselves to a pouch and continue developing there. Many marsupials also carry their young in their pouches even after they’re fully developed, to protect them from predators and shield them from the elements. Koalas are around the size of small dogs, growing up to 33 inches long and weighing up to 33 pounds. They’re famous for their cute, teddy-bear-like appearance, but there’s a lot more to them than that.
 
Even among marsupials, koalas are oddballs. It’s thought that their name originates from the Dharug language, in which it means “no drink” or “no water.” Indeed, koalas almost never drink water directly, unless there’s a fire or particularly devastating heat wave. Instead, they get all their water from their only source of food: Eucalyptus leaves. Yes, koalas only eat one thing, and it’s poisonous. Most animals would die from consuming eucalyptus, but koalas have special liver enzymes and gut fauna that allow them to digest the toxic leaves with no issue.
 
There’s a price to pay for their unusual diet, though. First of all, eating just one thing means that koalas can’t adapt to other environments very well, so deforestation and diseases that affect eucalyptus trees inevitably devastate koala populations. Then there’s the fact that digesting poisonous leaves requires a lot of energy, which means that koalas have to conserve it in other areas. This is part of the reason that they spend up to 22 hours a day sleeping. It might also contribute to their extremely small brain size. Koalas have one of the smallest brain-to-body mass ratios in the entire animal kingdom, with their brains making up just 0.2 percent of their body mass. As if that’s not embarrassing enough, koalas’ brains are also smooth, which makes complex or out-of-the-norm tasks (such as eating eucalyptus leaves from anything other than an actual branch) difficult for them to learn. Large, complex brains take a lot of energy to maintain, and koalas simply don’t have enough to spare. Despite koalas’ declining population, Australia regards them as a national symbol, and conservationists are doing all they can to preserve their habitats and fight the climate change and deforestation that impacts them. They may be small (and sleepy) but they’ve got a lot of dedicated people in their corner.

 
[Image description: A koala sitting in a tree, grasping leaves in its paws.] Credit & copyright: Sklmsta, Wikimedia Commons. This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication.

When it comes to the severity of flu infections, it’s often a matter of what you have, not what you lack. It’s common knowledge that older people are more vulnerable to the flu, and according to a paper published in PNAS by an international team of researchers, the culprit isn’t just weak immune systems. According to Kin-Chow Chang, a co-author of the paper from the School of Veterinary Medicine and Science at the University of Nottingham, understanding the mechanism behind severe flu symptoms in the elderly is a matter that requires urgent attention. As he explains, "Aging is a leading risk factor in influenza-related deaths. Furthermore, the global population is aging at an unprecedented rate in human history, posing major issues for health care and the economy.” To get to the bottom of the issue, Chang and his colleagues used an aging mouse model and samples of human tissue to observe how the immune system of an older population responds to the influenza virus. They discovered that older people produce more apolipoprotein D (ApoD), a glycosylated protein associated with lipid metabolism and inflammation. Higher levels of ApoD lead to more mitophagy, or the destruction of mitochondria. In the context of a viral infection, this means two things. First, since mitochondria produce cellular energy, higher rates of mitophagy means a weakened immune response. Two, the mitochondria also induce protective interferons, which inhibit viral replication. These two factors combine to make the elderly much weaker to a variety of viral infections, including the flu. People who are 65 or older account for 90 percent of flu deaths and up to 70 percent of flu-related hospitalizations, making them by far the most vulnerable population. With flu season just around the corner, this new knowledge won’t exactly have anyone breathing easy. Here’s hoping that this insight can lead to some solutions for older folks facing the flu.

Fuzzy and fossorial…what’s not to love? With their torpedo-shaped bodies, enormous, stout feet, and eyes that are practically invisible, moles have to be one of the strangest looking animals on Earth. Yet, unlike other famously odd animals like platypuses and echidnas which live on only one continent, moles are common on every continent except South America and Antarctica. It isn’t just their looks that are strange, either—most female moles have intersex qualities, meaning that they have characteristics usually only found in males.
 
Moles come in a variety of shapes and sizes, from bizarre star-nosed moles to fairly plain Eastern moles. They all share one important trait, though: they’re fossorial, meaning that they spend most of their lives underground. A single molehill (the part of a mole’s tunnel system that can be seen aboveground) can signal a vast underground network of tunnels stretching up to 230 feet. A single Eastern mole can dig an 18-foot-long tunnel in an hour. That’s pretty impressive for an animal that only grows to be around eight inches long.
 
Despite living in cozy homemade tunnels, moles don’t spend a lot of time relaxing. Their constant digging requires them to have a high metabolism, which in turn requires them to eat constantly. Moles spend nearly all their time hunting for worms, grubs, and other insects that live underground. While moles are formidable predators in their chosen environment, things are very different when they’re forced aboveground by tunnel cave-ins, flooding, or a lack of food. Moles are extremely vulnerable aboveground due to their small size and poor eyesight. Because their large feet are made for digging rather than running, moles are slow aboveground and can easily be killed by foxes, snakes, or birds of prey.
 
Despite these vulnerabilities, moles have managed to thrive throughout most of the world for over 30 million years—and it’s not just because they stay underground. Moles have a unique approach to reproduction that helps both female moles and their offspring survive. In many mole species, female moles have both ovarian and testicular tissue, meaning that they produce egg cells along with large quantities of testosterone. This added testosterone makes female moles far more aggressive than those of most other mammalian species. After giving birth to two to seven pups in a specially-made underground nesting chamber, mother moles will viciously fight off any threat to their young, including large, aboveground predators like foxes, even when there’s little chance of success. Don’t poke the mama mole!

 
[Image description: A black-and-white illustration of a mole.] Credit & copyright: Dead Mole, Wenceslaus Hollar, 1646. Harris Brisbane Dick Fund, 1917, The Metropolitan Museum of Art. Public Domain.

It seems you can never breathe easy these days. According to a new study by the National Institute of Standards and Technology (NIST) published in ASTM International, air purifiers can sometimes release harmful byproducts into the air, and researchers have figured out a way to measure just how much. It seems paradoxical, but air purifiers aren’t always good for the air. They can use a variety of processes that create toxic byproducts. The most common of these is the ozone produced by UV lights meant to kill pathogens. Normally harmless in low concentrations, the ozone can sometimes accumulate enough to pose a threat to the user’s health. Other byproducts include formaldehyde and ultrafine particles, which are produced by an unintended interaction between the components of the air purifier. To test which air purifier models harm more than they help, the NIST developed a test to measure the pollutants. During the test, the air purifier is left running in a sealed room for four hours. Samples of the air are then taken. Then, a UV light is shone so that researchers can measure the amount of ozone and formaldehyde present in the samples, since both substances absorb UV radiation. To measure ultrafine particles, researchers use a method called scanning mobility particle sizing (SMPS), which passes the samples through an x-ray field. The x-ray imparts an electric charge on any particles that might be present, making it easier to sort ultrafine particles from larger ones, since they hold different amounts of charge. Once the ultrafine particles are isolated, they’re placed in a cool steam bath, which makes them swell in size. Then, lasers can be used to determine how much is present by measuring how much the particles scatter the light. It’s a lot of work to figure out how many impurities these purifiers are leaving behind, but there’s no doubt that it needs doing.

Would you believe that hypertension is all in your head? According to a new study published in Neuron by researchers at McGill University, the mechanism behind high blood pressure resulting from a high-salt diet might lie in the brain. High-salt or high-sodium diets have long been associated with an increased risk of heart disease as a consequence of high blood pressure. The longstanding theory was that high sodium acted directly on the kidneys and blood vessels, constricting them and leading to hypertension. Most treatments have been based on that assumption. Yet, around one-third of patients with salt-induced hypertension don’t respond to medication, and the reason was unclear—until now. Researchers conducted an experiment in which rats were given water with two percent salt, creating a diet containing comparable rates of sodium to a typical human diet. The diet triggered an immune response in the rats’ brains, leading to inflammation that in turn led to the brain releasing increased quantities of vasopressin, a hormone produced in the hypothalamus responsible for osmolality (the balance of salt and glucose). According to lead researcher Masha Prager-Khoutorsky, the brain is a particularly difficult organ to analyze, and this new study was only possible due to recently developed brain imaging and lab techniques. If the same mechanism can be confirmed in human subjects, future treatments of hypertension might focus on medications that act on the brain to reduce the inflammation or counteract the effects of vasopressin itself. Who knew that treating hypertension would be so-dium confusing?

[Image description: A glass salt shaker tipped on its side with salt spilling out.] Credit & copyright: Garitzko, Wikimedia Commons. The copyright holder of this work has released it into the public domain. This applies worldwide.
 

They might howl in the night, but there’s no need for fright! Coyotes are often compared to wolves, yet while gray wolves (the most common North American species) remain endangered, coyotes are listed as a “species of least concern” with an increasing population. This difference is largely due to the fact that, despite looking like small, lean wolves, coyotes live very differently than their wolf brethren.
 
Native to central and North America, coyotes thrive in a variety of habitats, from deserts to forests to, surprisingly, suburban areas. They are larger than foxes but smaller than wolves, measuring up to 52 inches long and 26 inches tall. Live wolves, they live in packs consisting of a dominant, mated pair, and their children, including a mix of younger and older pups. Usually, there are only three to seven coyotes per pack, compared to gray wolf packs that often range between 10 to 20 individuals.
 
Smaller pack sizes seem to suit coyotes just fine, since they don’t prey on animals nearly as large as the caribou and bison that gray wolves do. Instead, coyotes hunt small mammals like rabbits and rodents…when they hunt at all. A key to coyotes’ survival, even in the face of climate change and habitat loss, is their highly adaptable diet. Coyotes can live off of a mix of freshly-hunted meat, carrion, wild fruit, and even garbage left behind by humans. In fact, coyotes that live near suburban areas are routinely caught raiding trash cans. They also employ other tricks to survive, like their unique howling style full of yips and changing notes. When these howls echo over long distances, they can easily make it sound like a coyote pack is much bigger than it actually is, thus scaring away potential threats. As scary as coyotes seem to some people, they actually have to worry about falling prey to larger animals like bears, mountain lions, and even wolves. Family resemblance won’t save you in the wild.

 
[Image description: A coyote walking in a desert landscape, looking back over one shoulder.] Credit & copyright: Cape Hatteras National Seashore, NPS, Asset ID:347d7710-ba38-4735-809b-9f82bc9c8437. Public domain: Full Granting Rights.

What do real estate planning and tree planting have in common? Both are all about location, location, location! It’s common knowledge that planting trees helps mitigate the effects of climate change, but a new study published in Nature by researchers at University of California, Riverside (UCR) shows that trees are actually more effective at helping in some locations than others. Trees can help lower temperatures in two ways: by reducing the amount of carbon dioxide in the atmosphere and sequestering it as biomass, and via a process called evapotranspiration, in which trees take water from the soil and release it as vapor. Evapotranspiration tends to have a greater impact on global temperatures because the process makes air more humid, which in turn leads to more clouds that reflect sunlight. The UCR researchers were looking into evapotranspiration’s effectiveness in different locations, and found that trees in the tropics, where the climate is warmer and more humid, are better at cooling the air. Using computer models, researchers compared the effects of additional trees planted globally to that of trees planted in the tropics. In the former, the mean cooling from the additional trees was 0.01 degrees Fahrenheit, and in the latter, the mean cooling was 0.1 degrees Fahrenheit. The effect could be even greater in more specific locations, with additional trees in central Africa reaching 0.8 degrees Fahrenheit of cooling. When accounting for the cooling effect of lowering atmospheric carbon, there was an additional 0.15 degrees Fahrenheit of difference. They also found that trees can reduce the risk of wildfires in grassy areas like savannas, since they’re more resistant to burning and limit the spread of fire. There are times that trees can raise ambient temperatures, though. In areas with snow, trees can absorb more heat than the surface around them due to their darker color, offsetting the effects of evapotranspiration. When it comes to cooling the atmosphere, green is usually (but not always) good.

[Image description: A dense tropical forest.] Credit & copyright: Gerda Arendt, Wikimedia Commons. This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication.
 

There’s plenty of fish in the sea, but when it comes to manta rays, there’s only three! Scientists have recently discovered and described a brand new species of manta ray, which they’ve named Mobula yarae, after Yara, a water spirit of Brazilian myth. Also known as the Atlantic manta ray, this new species is similar in size to the giant oceanic manta ray, with a wingspan between 16 and 20 feet, its coloration is unique. The Atlantic manta ray has dark abdominal spots, a light-colored face, and V-shaped white patches on its shoulders, making it distinct from the reef manta, with which it shares a habitat. Atlantic manta rays are found in tropical, coastal Atlantic waters from the U.S. to Brazil.
 
Though they look a bit like underwater birds, manta rays are, in fact, a type of fish. Their powerful “wings” are actually fins designed to help them glide through the water at speeds of up to nine miles-per-hour. While that isn’t as fast as famous predators like sharks, it’s speedy enough to allow water to flow through manta rays’ open mouths so that they can filter-feed on plankton. Their speed also allows them to rush toward the water’s surface and leap into the open air, which they do en masse during yearly mating rituals. Manta rays only have one baby, called a pup, every one to two years. This low birth rate hasn’t helped their struggling numbers—the giant oceanic manta ray is endangered, while the reef manta is considered vulnerable.
 
Manta rays live mostly solitary lives, but when they get together, they really do it right. Giant manta rays sometimes group together in the hundreds to migrate in search of food. When a particularly dense patch of plankton appears, hundreds of manta rays can converge on one spot, moving together in a giant spiral to feed. Since a single giant oceanic manta ray can weigh up to 3,600 pounds, you could say that mantas rays’ parties carry a lot of weight.

 
[Image description: A manta ray swimming upside down underwater.] Credit & copyright: Thewaydu, Wikimedia Commons. This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication.

Is this as big as they can get? It’s hard to imagine otherwise. Astronomers at the University of Portsmouth have found what could be the largest black hole ever discovered, according to a paper published in Monthly Notices of the Royal Astronomical Society. Located around five billion light years away in the Cosmic Horseshoe galaxy, the black hole is at least one of the top 10 largest ever discovered. It’s not such a surprise that one of the most massive black holes would be found within one of the most massive galaxies, but the sheer scale is still a bit jarring. The supermassive black hole located at the heart of the Milky Way galaxy, Sagittarius A*, contains the mass of 4.15 million suns. On the other hand, the new discovery is an ultramassive black hole and is estimated to have the mass of 36 billion suns. What might be even more surprising is how it was discovered. Unlike most known black holes, this one does not have an accretion disk. That means it’s not actively consuming the matter around it, and that it lacks the telltale x-ray emissions produced by accreting matter. Instead, the black hole was given away by its sheer mass, which warped the space-time around it enough to cause gravitational lensing, a phenomenon in which the light coming from behind an object is visible along its edges. Even the Cosmic Horseshoe itself gets its name as a result of this phenomenon, since it is framed by a horseshoe-shaped ring of light. It must run in the family.

[Image description: A starry sky with the milky way visible.] Credit & copyright: NPS/Patrick MYers, Asset ID: 707ecd39-53dd-47a2-8dad-33178eac3992, National Park Service Digital Asset Management System. Constraints Information: Public domain: Full Granting Rights.
 

That’s not an enormous bird blotting out the sun…it’s a mammal! Flying foxes, specifically the 60 or species in the genus Pteropus, are the largest bats in the world. Those suffering from a bit of a bat phobia have nothing to fear, though. These high-flying mammals don’t drink blood or even eat insects; they feast on fruit.
 
Flying foxes mainly live in tropical regions of Asia, Australia, Madagascar, and some Pacific islands. There, they have abundant, year-long access to all sorts of fruits, and they certainly make the most of it. Many species of flying foxes eat up to half their body weight in fruit, pollen, and nectar each day. All that food helps fuel their impressively large bodies. The biggest species of flying fox, the giant golden-crowned flying fox, has an average wingspan of around 4.9 to 5.6 feet and can weigh up to three pounds.
 
A flying fox’s environment must have enough food to support not just a few individual bats, but entire colonies. Most flying foxes are social, living in groups that can range from a few dozen bats to several hundred. Unlike many, smaller bats, which remain in a fixed location each year, flying foxes are nomadic. Each year, they can fly thousands of miles in search of food. Luckily, flying foxes help maintain the very fruit they depend on to live, spreading pollen via their fur and seeds via their droppings.
 
Like most bat species, flying foxes are nocturnal. During the day, they hang upside down, high in the forest canopy (with young bats clinging to their mothers until they’re ready to fly on their own.) There, they sleep and groom one another while waiting for nightfall. Flying foxes’ entire lives revolve around trees, which means that habitat destruction, especially as part of the logging industry, is particularly devastating to them. Sadly, nearly half of all flying foxes are either threatened or endangered. Here’s hoping that intensifying conservation efforts can keep these gentle giants airborne.

 
[Image description: A large, brown-colored bat flying against a blue sky.] Credit & copyright: Map9994, Wikimedia Commons. This work has been released into the public domain by its author, Map9994, at English Wikipedia. This applies worldwide.

Whether you’re a human being or a cockroach, pregnancy is draining. According to a paper published in the Journal of Experimental Biology, researchers at the University of Cincinnati have discovered that some species of cockroaches need more sleep when they’re pregnant, just like people. The Pacific beetle-mimic cockroach (Diploptera punctata) is something of an oddball among insects. Instead of laying eggs like most roaches, they give live birth, but that’s not all. During the three-month gestation period, these roaches feed their young from a broodsac using milk protein. This is called viviparity, and it’s somewhat similar to the way mammals use a placenta to nourish their young during gestation. The similarities to mammals don’t end there: just like human mothers need to get plenty of sleep, these roaches also require sleep for healthier gestation and offspring. The need for rest is so important that, according to the research, pregnant D. punctata don’t travel as far in search of food, indicating an aversion to risk-taking behavior. The relationship between sleep and pregnancy complications in humans are poorly understood, which is why the roaches are of such interest to researchers. In humans and mammals in general, sleep disturbances can significantly impact embryo development, and if similar issues affect D. punctata, studying the roaches might give some clues as to why. No matter the species, being a mom is hard work.

[Image description: A close-up photo of a brown cockroach.] Credit & copyright: Junkyardsparkle, Wikimedia Commons. This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication.
 

Even two dozen limbs can’t help you outrun a pandemic. Since 2013, billions of sea stars, also known as starfish, have died due to a mysterious wasting disease. Now, scientists have finally pinpointed the bacteria responsible for the plague, giving hope that conservation and disease-management programs can save these unique ocean creatures. No species was hit harder by the disease than the sunflower sea star, whose population has decreased by a whopping 90 percent since the plague was first noticed.
 
Sunflower sea stars come in a variety of colors, from reds, yellows, and oranges, to various shades of purple. Unlike sea stars that resemble a traditional five-pointed star, sunflower sea stars have between 16 and 24 limbs, making them look more like sunflowers. They differ from other sea stars on the inside, too. Their skeletons aren’t solid, like most sea stars’. Instead, it’s made of disjointed, bone-like discs, or ossicles. This makes sunflower sea stars extremely flexible, which comes in handy when hiding from predators and while hunting. Though they may not look much like predators, sunflower sea stars are just that. Their arms are covered in eye spots which help them discern light from dark and allow them to locate potential prey. The bottoms of their limbs boast up to 15,000 thin, almost hair-like tube feet, allowing them to crawl across the ocean floor at speeds of up to 3.3 feet per minute. For sea stars, that’s pretty fast! It’s certainly speedy enough to hunt down their favorite prey: other invertebrates. Sunflower sea stars are completely carnivorous, dining on sea urchins, clams, and crustaceans.
 
These many-armed critters have a large range across the Northeast Pacific Ocean, from the coastal waters of Alaska to Mexico. Unfortunately, in recent years their population has dwindled due to a devastating, worldwide plague of sea star wasting disease. The mysterious illness causes sea stars’ bodies to break out in lesions and completely disintegrate. Since 2013, over five billion sea stars have died from the disease. Now, researchers have finally discovered the cause of the illness: a bacteria called Vibrio pectenicida. With this knowledge, steps can finally be taken to save the sea stars. That might involve breeding sea stars that are immune to the bacteria and then releasing them into the ocean, or feeding wild sea stars probiotics to help them fight the bacteria off. Hopefully, this isn’t the last we see of these sunflowers of the sea.

 
[Image description: A group of reddish-colored sunflower starfish in shallow water.] Credit & copyright: NPS Digital Asset Management system. Asset ID: 2D7F9806-A3B5-ABD1-9B952DA866AA90E2. Constraints Information: Public domain.

Some voices can be heard for a country mile. According to a paper published in JASA Express Letters, researchers at Indiana University have found that twangy voices are the easiest to hear over loud noises. Apparently, twangy, female voices are the easiest to understand in an environment filled with neutral noise. However, “twangy” doesn’t just refer to the stereotypical country accent, but includes those found in major U.S. cities like New York and Chicago. These voices have what the researchers called “bright” and “brassy” qualities. In the study, researchers took four male and four female participants with twangy voices and had them record speech samples. When played along with background noises like plane or train sounds, listeners were able to understand the twangy voices better than ones with a “neutral” accent. Although the reason for this isn’t clear, it may have to do with the fact that twangy voices tend to have a higher pitch than neutral ones. High-pitched sounds are perceived more clearly than low-pitch sounds, especially when ambient noise is also low pitched, which it often is. They also believe that a twangy timbre might have applications in voice therapy, which allows the speaker to “maximize acoustic output while minimizing effort.” You could call it a different kind of talk therapy.

[Image description: A digital illustration of a word bubble with three exclamation points inside, with four curved lines representing soundwaves.] Credit & copyright: Author-created image. Public domain.
 

These mermaids are a bit chunkier than the fairy tales claimed. Famously mistaken for mermaids at various points in history, manatees have managed to remain humble, drifting through warm, shallow waters at a leisurely pace of around five miles per hour. These friendly aquatic mammals are often compared to seals, but their true lineage is much more surprising.
 
Manatees have earned their distinction as gentle giants. They can grow up to 10 feet long and weigh up to 1,200 pounds, on average. They’re friendly enough to be tourist attractions, floating alongside snorkeling travelers. They’re not the only giants in their family tree, either. Manatees’ closest living relatives are elephants, though the two species obviously evolved in very different directions after splitting from their common ancestor around 60 million years ago. Their interesting lineage and general appearance, from their cow-like faces (from which they get their nickname “sea cow”) to their pudgy bodies, makes it all the more intriguing that they were once mistaken for mermaids. It does make some sense, considering that early Europeans often painted animals from the “new world” without ever having seen them in person, which could lead to discrepancies when one actually came across them. After seeing manatees for the first time in 1493, Christopher Columbus wrote, “Yesterday, when I was going to the Rio del Oro, I saw three sirens that came up very high out of the sea. They were not as beautiful as they are painted since, in some ways, they have a face like a man.” Despite Columbus’s scathing assessment, Manatees (along with dugongs) are part of the order Sirenia, named after mythical sirens, or mermaids.
 
Manatees frequent coastal waters in certain areas of North America, South America, the Caribbean, and West Africa, where they live mostly solitary lives, feeding on aquatic vegetation like algae and kelp. Although West Indian Manatees (which includes those sometimes called “Florida manatees”) haven’t been listed as endangered since 2017, they still face plenty of threats. They’re too big to be harmed by most natural predators, but habitat loss, dangerous pollution, and collisions with boats have all taken a toll on global manatee populations. Boat collisions can be especially deadly, and conservationists suggest that boaters avoid shallow waters and wear polarized sunglasses to better spot manatees beneath the surface. Crashing into a mermaid has got to bring bad luck.

 
[Image description: A manatee floating underwater surrounded by small fish.] Credit & copyright: Ramos, Keith, USFWS. USFWS National Digital Library. Public Domain.

When playing the genetic lottery, your odds may be worse than a coin flip. A recent paper published in Science Advances by researchers from Harvard University shows that the odds of a couple giving birth to a male or female baby might not be quite as even as previously thought. Aside from intersex conditions like extra chromosomes, androgen insensitivity syndrome, and other cases where a person’s gender doesn’t necessarily match up neatly with their chromosomes, the formula for a male or female person is simple. Two X chromosomes, one from each parent, results in a girl. One X chromosome from the mother and one Y chromosome from the father results in a boy. And since each sperm has a 50/50 chance of carrying either an X or Y chromosome, it would seem that the birth rate for each sex would be the same. Not really, though. Researchers looked at data regarding 58,007 women in the U.S. who collectively gave birth to 146,064 children between 1956 and 2015. Instead of finding a simple binomial distribution of the sexes, they found a beta-binomial distribution, meaning that families could tend to skew toward producing one sex more than the other. The researchers compared it to a weighted coin toss, where the odds weren’t completely random. One of the telltale signs was that it was much more common than it should have been for some families to have all boys or all girls. A possible factor appears to be the age of the mother, as women 28 and older had an elevated chance of giving birth to multiple children of one sex over another. Researchers noted that the data might be affected by a behavior they call “coupon collecting,” which is when a couple continues to have children until they have a child of their desired sex. Compared to actual coupon collecting, that sure sounds expensive.

[Image description: The symbols for “female” and “male” with a pink-and-blue background.] Credit & copyright: Author-created image. Public domain.