6-30-21 Could polar bears be established in the Antarctic to save the species?
Polar bears could be transported to the Antarctic, but they would almost certainly destroy the wildlife that is currently there and then die out themselves. In the Antarctic, penguins breed in large numbers and have no land-based predators. If the penguins weren’t at sea, polar bears would find an all-you-can-eat buffet that they would enjoy until it was wiped out. The bears would then have to turn to the seals, which, unlike the ones in the Arctic, also have no predators on the ice and would be easy pickings for polar bears until they too were all gone. This would in turn spell doom for the bears. It would be preferable for efforts to be put into saving the current habitat of polar bears, so that these magnificent creatures can survive in their natural location. Imagine a northern bear just completing its hibernatory period, eager to emerge from its snow hole. But if transported to the southern hemisphere, it would be time to hibernate again. It would be extremely reckless to try to introduce polar bears into the Antarctic in order to save them from extinction. The Antarctic species that the bears would be likely to prey upon have evolved no defences to polar bear predation and would be likely to suffer catastrophic losses. While not every introduction of animal or plant species into places that are outside their natural range has resulted in disaster, there is a very long history of introductions that have proven ecologically disastrous. The bleak Antarctic mainland is a far more challenging environment than the islands and sea ice of the Arctic. Polar bears might do well on islands off mainland Antarctica where there are an abundance of seals and penguins to hunt. This, however, wouldn’t be allowed. The entire Antarctic is an internationally protected area and alien species such as reindeer (introduced by whalers for fresh meat) and rodents (which always just turn up with humans) have already been exterminated. An apex predator such as a bear would do intolerable damage to existing ecosystems.
6-30-21 Amazing surfing sharks image shows how currents help them save energy
THE grey reef sharks in this shot seem to be just hanging in the water in a behaviour never reported before in these animals. Working in an international team of researchers, Laurent Ballesta at Andromede Oceanology in France snapped this cohort of grey reef sharks (Carcharhinus amblyrhynchos) in the South Pacific Ocean. They were swimming against water currents, but barely moving their tails. The research revealed that the sharks were floating using the upward movement from currents, effectively “surfing” and cutting their energy consumption by about 15 per cent (Journal of Animal Ecology, doi.org/gkdq). More than 500 grey reef sharks live in the southern channel of Fakarava atoll, a coral reef in French Polynesia. The team studied them using tags, cameras and observations. Surfing the channel with minimum effort gives the sharks a break from the continuous swimming that provides them with oxygen. During a diving trip, lead researcher Yannis Papastamatiou at Florida International University observed the sharks using a conveyor belt-like system to surf: the one at the front lets the current carry it to the back of the line and another shark takes its place. The study reveals what Papastamatiou calls energy seascapes: spatial representations of the energy it costs an animal to move through a marine environment. It might explain, says the researchers, why large groups of sharks gather in certain areas of ocean.
6-29-21 Meerkats in zoos don’t put as much effort into social niceties
Meerkats in zoos fight over food more aggressively, are pickier about which of their peers they groom and have less stable relationships than those living in the wild. This may be due to living such a comfortable life, free of predators and with food and housing reliably available without having to work together for it, says Xareni Pacheco at the Autonomous University of Mexico State. “In a confined space, where conditions rarely change and are fairly predictable, individuals may freely adjust their social dynamics with the group members at any moment, without losing benefits like food, reproductive mates or predation protection,” she says. Pacheco built her study of meerkats on the decade-long work of her colleague Joah Madden at the University of Exeter, UK. Madden’s team observed the social interactions of more than 100 living in eight groups in South Africa. It was a “unique opportunity” for studying non-primates in the wild, because the groups had become habituated to humans and let the researchers study them up-close and in detail, he says. He and his colleagues used this information to develop a behaviour checklist specifically for studying meerkat social networks. Using Madden’s chart, Pacheco spent 300 hours observing 113 meerkats living in 15 groups across 13 zoos in the UK and Mexico, most of which had enclosures that closely resemble their native southern African habitats. She recorded 5689 social interactions. Pacheco found that the meerkats in captivity were more selective when choosing which friends to groom, resulting in less popular meerkats rarely getting groomed. Dominant meerkats also fought with fewer individuals but more aggressively, growling at, “hip-slamming” and biting other individuals. Previous studies have compared the behaviour of wild and captive primates, birds and fish, but this is the first one to directly compare specific interactions using animals in so many groups.
6-29-21 These beetles walk on water, upside down, underneath the surface
The insect’s inverted surface scurrying is a rare method for getting around. Being quite small, insects can have a very different relationship with the water-air interface than larger animals do. Surface tension allows for insects like water striders to skate along the top of still waters, for example. But new research reveals an unusual way to tread along this boundary: from the underside. A water-dwelling beetle can scuttle upside-down along the underside of the water’s surface, as if the water were a solid pane of glass, researchers report June 28 in Ethology. It’s the first detailed documentation of a beetle moving in this manner, which is known only in precious few animal groups. John Gould, a behavioral biologist at the University of Newcastle in Callaghan, Australia, hadn’t set out to look for beetles one night in the country’s Watagan Mountains, searching instead for tadpoles in ephemeral pools. In one of these pools, he spotted a black object smaller than a pinky nail. “At first, I just assumed it must have been a bug that had fallen into the water and was swimming across the surface,” Gould recounts, “but then realized the bug was upside-down and below the water’s surface.” As Gould quickly filmed the scene, the beetle walked under the water’s surface just as it would on a flat, solid surface, periodically resting and changing direction. Later, Gould mentioned the encounter to his colleague Jose Valdez, a wildlife ecologist at the German Centre for Integrative Biodiversity Research in Leipzig. Valdez thought the observations were interesting, but he’d seen insects walk upright under water before. “I didn’t fully grasp what he was describing until he showed me the video,” says Valdez. “Then I was floored.” Searching the scientific literature, the researchers found that some snails could slide along the underside of the water’s surface on a layer of mucus, but little documentation of beetles walking this way existed — just passing mentions in decades-old papers.
6-28-21 An Australian mouse thought to be extinct still survives on an island
A mouse we thought went extinct 125 years ago is still clinging on. Gould’s mouse (Pseudomys gouldii) was considered to be confined to the Australian mainland and hadn’t been seen there since 1895, but researchers now think it is still surviving on a small Australian island. Emily Roycroft at the Australian National University in Canberra and her colleagues set out to look at the genetic diversity of extinct Australian rodents. The researchers took DNA samples from specimens of eight extinct Australian rodent species, including Gould’s mouse, from museum collections in Australia and London. They then compared them with their living relatives around Australia. Unexpectedly, the analysis revealed that the so-called Djoongari or Shark Bay mice living on an island in Shark Bay off the coast of Western Australia are actually Gould’s mice. “Some good news is that a beautiful small animal, which was once distributed across most of Australia, is not an extinct species as feared,” says Kristofer Helgen at the Australian Museum Research Institute. “This gives us a welcome ‘second chance’ to save this endangered species, so we better be sure to take it.” What’s more, the team found that the genetic diversity of Gould’s mice and other, now extinct rodents collected in the 19th century was relatively high. This suggests that these species were around in large and potentially stable populations right before they vanished from Australia, which disproves the idea that they were already on their way out before Europeans colonised Australia, says Roycroft. European colonisation may have contributed to these extinctions through the introduction of animals such as cats and foxes that ate the native wildlife, changes to indigenous fire management practices, the introduction of new diseases and habitat destruction due to industrialisation and land clearing for agriculture.
6-28-21 A proposed ‘quantum compass’ for songbirds just got more plausible
A protein in European robins’ retinas showed sensitivity to magnetic. Scientists could be a step closer to understanding how some birds might exploit quantum physics to navigate. Researchers suspect that some songbirds use a “quantum compass” that senses the Earth’s magnetic field, helping them tell north from south during their annual migrations (SN: 4/3/18). New measurements support the idea that a protein in birds’ eyes called cryptochrome 4, or CRY4, could serve as a magnetic sensor. That protein’s magnetic sensitivity is thought to rely on quantum mechanics, the math that describes physical processes on the scale of atoms and electrons (SN: 6/27/16). If the idea is shown to be correct, it would be a step forward for biophysicists who want to understand how and when quantum principles can become important in various biological processes. In laboratory experiments, the type of CRY4 in retinas of European robins (Erithacus rubecula) responded to magnetic fields, researchers report in the June 24 Nature. That’s a crucial property for it to serve as a compass. “This is the first paper that actually shows that birds’ cryptochrome 4 is magnetically sensitive,” says sensory biologist Rachel Muheim of Lund University in Sweden, who was not involved with the research. Scientists think that the magnetic sensing abilities of CRY4 are initiated when blue light hits the protein. That light sets off a series of reactions that shuttle around an electron, resulting in two unpaired electrons in different parts of the protein. Those lone electrons behave like tiny magnets, thanks to a quantum property of the electrons called spin. The two electrons’ magnets can point either parallel to one another or in opposite directions. But quantum physics dictates that the electrons do not settle on either arrangement. Rather they exist in a limbo called a quantum superposition, which describes only the probability of finding the electrons in either configuration.
6-28-21 An ecologist’s new book gets at the root of trees’ social lives
In ‘Finding the Mother Tree,’ Suzanne Simard recounts discovering forests’ hidden networks. Opening Suzanne Simard’s new book, Finding the Mother Tree, I expected to learn about the old growth forests of the Pacific Northwest. I had an inkling that Simard, a forest ecologist at the University of British Columbia in Vancouver, would walk through her painstaking research to convince logging companies and others that clear-cutting large parcels of land is too damaging for forests to recover. I didn’t expect to be carried along on her very relatable journey through life. Simard was born in the Monashee Mountains of British Columbia in 1960. Her family of loggers selectively cut trees and dragged them out with horses, leaving plenty still standing. In her first stab at a career, she joined a commercial logging company that clear-cut with large machinery. Her job was to check on seedlings the firm had planted in those areas to restart the forest. The fledgling plants were often yellowed and failing. Simard’s instincts told her those trees were missing the resources that exist within a diverse community of plants, so she set out to see if her hunch was right. She learned how to do experiments, with close calls with grizzly bears and other mishaps along the way, eventually becoming a tenured professor. She and colleagues discovered that underground networks of fungi among tree roots shuttle carbon and nutrients from tree to tree (SN: 8/9/97, p. 87). Simard seamlessly weaves details of her studies of these networks with her life’s travails: sibling relationships and loss, struggles as a woman in a male-dominated field and her own recovery from a health crisis. Like many women who work outside the home, she felt torn between being with her young daughters and pursuing her professional passions. Readers will feel for Simard as much as they worry for the forests that are quickly disappearing. Simard presents plenty of evidence and writes enthusiastically to build her analogy of the “mother trees” — the biggest, oldest trees in a forest that nurture those nearby. In her experiments, seedlings planted near a mother tree were much more likely to survive.
6-27-21 Appeal to identify 'La Botaniste' who slipped from history
When sorting through books gathering dust in the attic, it's common to find mementos of the past such as a poem, a pressed-flower, or a letter. But when staff at the Royal Horticultural Society (RHS) went through hundreds of old plant books, they stumbled on a collection of botanical treasures the likes of which they'd never seen before. Tucked inside a copy of The English Flora from 1830 were poems, doodles, plant specimens and a cartoon. Judging by the contents, the owner was a keen plants woman. But her name, Isabella A Allen, appears to have slipped from history. She may be the early 19th Century botanical illustrator about which little is known. Or she could be among the legions of uncelebrated 19th Century women with a passionate interest in plants. Either way, the RHS is hoping to track her down to find out more about her life. "All we've got is a reasonably common name and lots of contextual stuff that she's interested in botany," says head of libraries and exhibitions, Fiona Davison. "What I'm hoping is that somebody is aware in their family tree of an Isabella A Allen, that they've got any information about being a botanical artist or involved in botany." The book the unknown botanist scribbled in was by a weighty scientific author, Sir James Edward Smith, from a time when botany was a popular scientific subject for women in the higher social classes. Botany was an area where they could make discoveries and be part of a broader scientific community. Many contributed to herbaria, the collections of preserved plants that form the cornerstone of botanical study, while others were skilled botanical artists. "I think she clearly is a keen botanist because pressed in a number of the pages are wild flowers," says Fiona, listing kidney vetch, cranesbill, louse wort and sow thistle, among others. "They're wild flowers when you're out on a botanising trip you would have picked up, identified with the help of the book and pressed."
6-26-21 Thousands of pigeons are missing in England in a 'Bermuda Triangle-style mystery'
Millions of people went about their business as usual last Saturday, utterly oblivious to the fact that it was "one of the very worst ever" days in pigeon racing history. A week ago, some 9,000 birds were released from Peterborough, in eastern England, bound for the North East in what was supposed to be a three-hour race (yes, this is apparently a whole thing). But nearly a week later, The Sun reports that "thousands" of birds are still missing in "a Bermuda Triangle-style mystery." "At present people are very unsure what has happened — there are still lots and lots of pigeons still missing in action," Richard Sayers, a pigeon fancier, wrote on social media. "A lot of people think this is due to something in the atmosphere — like a solar storm above the clouds." But the mystery might have a simple explanation: the pigeons simply wanted to ditch the rain in Peterborough this week and go on vacation. Expats in Majorca, Spain, claimed to The Sun that they'd come across at least several of the "tired and disorientated" British birds.
6-25-21 Male birds’ feathers become duller when wildfires burn their habitats
All fire and no rain makes fairywrens very dull birds. As the climate warms and wildfires become increasingly common, these birds are coping by ditching their bright plumage to blend in better with the burnt landscape. Jordan Boersma at Washington State University in the US was studying the physiology of the red-backed fairywren (Malurus melanocephalus), an energetic little bird native to the grasslands of Northern Australia when he and his team made this discovery. “I was in the middle of another experiment when this wildfire came through and burned up all of the breeding territories,” he says. With all of the nest sites burned just before the birds’ breeding season, Boersma and his colleagues decided to shift focus. As they observed the birds move into their breeding season, they noticed that the males, who typically become more vibrant with jet-black feathers and their namesake splash of red across their backs to attract females, just didn’t. Instead, they stayed drab and brown. Even the older males who don’t have many remaining breeding seasons simply sat it out. The team had taken blood samples from the birds before the fire and compared them to samples after the nesting sites had been destroyed. They found that the drab male birds had suppressed testosterone levels, but all other signs pointed to good health. “This is a species that’s adapted to fire because it evolved in savannahs that tend to burn,” said Boersma. He argues that if there’s no place to nest, it might not be worth the risk of switching to bright colours that may catch the eye of a hungry predator. Instead, delaying or skipping the breeding season altogether would be a safer bet. The fairywrens are clearly no strangers to fire, but what remains unclear is exactly how skipping consecutive breeding seasons due to droughts and increasingly furious fires will affect the birds’ population numbers in the future.
6-24-21 A 'mysterious illness' is plaguing birds and baffling scientists across parts of the U.S.
A "mysterious illness" is plaguing "hundreds" of birds across the southern and midwestern U.S., leaving them with "crusty eyes, swollen faces, and the inability to fly," say The Guardian and HuffPost. Reports of such afflictions began in the spring, and scientists are still unsure as to their cause. Other potential symptoms include seizures or loss of balance — birds may even "just sit still, often kind of shaking," said Kate Slankard, a biologist of the Kentucky Department of Fish and Wildlife Resources. In Kentucky, blue jays, common grackles, and European starlings are among the species most affected, while the Wildlife Center in Ohio said on Facebook it had been "admitting songbirds with eye issues." Indiana officials made sure to test afflicted birds for avian influenza and west Nile virus, but both samples came back negative, reports the Guardian. States like Maryland, Virginia, West Virginia, and Washington, D.C. have also reportedly seen cases, writes HuffPost. The U.S. Geological Survey has recommended people refrain from feeding the avian creatures "until this mortality event has concluded," as birds congregating around feeders and baths can transmit disease to one another, the Guardian writes. The USGS also recommends, for the time being, cleaning feeders and baths with a 10 percent bleach solution, and avoiding the handling of birds. "This is truly scary," said Jim Monsma of Washington, D.C. wildlife rescue group City Wildlife to DCist last week. "And it's just every day more and more birds."
6-24-21 Chinese mountain cats swap DNA with domestic cats, but aren’t their ancestors
On the Qinghai-Tibetan Plateau, domestic cats have gotten some genes from wildcats. Wild Chinese mountain cats aren’t the ancestors of domestic cats, but the two types of felines still swap genes. The wildcats’ DNA is inscribed on the genes of some pet cats living on the Qinghai-Tibetan Plateau, but the mixing of genetic material extends back only a couple dozen generations, researchers report online June 23 in Science Advances. Cats and humans have lived together in China for at least 5,300 years, yet previous genetic studies on feline domestication hadn’t included DNA from East Asian cats (SN: 12/17/13). So researchers wondered whether the mountain cats (Felis silvestris bieti or Felis bieti) had ever contributed to Chinese pets’ genes. Yes, the team found, but the short length of time mountain cats and housecats have been mating suggests Chinese domestic cats have their origins elsewhere, probably in the Middle East (SN: 6/19/17). Shu-Jin Luo, a geneticist at Peking University in Beijing, and her colleagues came to that conclusion after they compared DNA from 27 Chinese mountain cats, 239 Chinese domestic cats and four Asiatic wildcats. The researchers didn’t encounter the elusive Chinese mountain cats in the wild; instead, they took samples from museum pelts, roadkill carcasses and zoo animals. The team did collect samples from the house cats, however. Rural Chinese cats come and go as they please, so “Oh, he’s not home yet, so we’ll wait for [an] hour” became a familiar refrain, Luo recalls. Analysis showed that the pet cats’ DNA carried traces of mountain cat genetics up to 30 generations ago. The reason is “actually quite apparent, but nobody thought about it before,” Luo says. Domestic cats arrived on the Qinghai-Tibetan Plateau in the 1950s, most likely brought there by Han Chinese migrants. Census data show human population spikes in the region 70 years ago, coinciding with the earliest signs of hybridization of the wild and domestic cats, Luo says.
6-24-21 Clues to how birds migrate using Earth's magnetic field
The mystery of how birds migrate long distances over land and sea is a step closer to being cracked. By studying robins, scientists have found clues to how birds sense the Earth's magnetic field. Just as you might reach for a magnetic compass to find which way is north or south, birds are thought to have an in-built "living compass". A chemical in the eye that is sensitive to magnetism could be proof of this theory, according to a new study. Peter Hore, professor of chemistry at the University of Oxford, said it could be that birds can "see" the Earth's magnetic field, although we don't know that for sure. "We think we may have identified the molecule that allows small migratory songbirds to detect the direction of the Earth's magnetic field, which they undoubtedly can do, and use that information to help them navigate when they migrate thousands of kilometres," he told BBC News. For decades, scientists have been investigating how animals such as birds, sea turtles, fish and insects sense the Earth's magnetic field and use it to find their way. The European robin is a stalwart of studies into the in-built "living compass" birds may use to orient themselves using the Earth's magnetic field. One chemical contender is a molecule in the retina of the eye known as a cryptochrome. The Oxford team studied a purified form of the molecule in the lab to see whether it was fit for purpose as a magnetic sensor. They found it had the ability to form pairs of "radicals" that have high magnetic sensitivity. A radical is an atom or molecule that is highly chemically reactive. Prof Hore said the mechanism they have been investigating involves magnetically-sensitive chemical reactions initiated by light inside the bird's eyes - in their retinas, to be precise. "It looks possible - and I would put it no stronger than that at the moment - that these highly-specialised chemical reactions could give the bird information about the direction of the Earth's magnetic field and in that way constitute a magnetic compass," he explained.
6-23-21 We may finally know how migrating birds sense Earth's magnetic field
We may finally know the secret to how migrating birds can sense Earth’s magnetic fields: a molecule in their eyes called cryptochrome 4 that is sensitive to magnetism, potentially giving the animals an internal compass. The process may result in the animals seeing darker or lighter areas in their vision when they look in the direction of magnetic field lines, says Henrik Mouritsen at the University of Oldenburg in Germany. “You may be able to see where north is as kind of a shading on whatever else you would be seeing.” Previous work has shown that certain species of birds, such as the European robin (Erithacus rubecula), use Earth’s magnetic fields when they migrate, as well as using visual and other cues. Some European robins migrate south every northern hemisphere winter, for instance from Scandinavia to the UK, and return in spring. At least part of this ability is thought to lie in their eyes, because their magnetism sensing is disturbed in the absence of light. Mouritsen has previously shown that when birds are using their internal compass, the information is processed in the same parts of the brain that process vision. Suspicion had fallen on the cryptochrome 4 molecule because it is present in the eye’s light-detecting cells and has a structure that suggests it can be affected by magnetic fields. Now Mouritsen and his colleagues have shown how the molecule reacts to magnetic fields in the lab. The team found that in the presence of light, electrons can jump between different parts of the molecule, and between it and another molecule called flavin adenine dinucleotide (FAD), ultimately leading to the production of a compound called CRY4-FADH*. The process is suppressed by weak magnetic fields.
6-23-21 Fathom review: What happens when humans try to talk to whales
MOST of us introduce ourselves for the first time by saying hello and giving our name. But what if you were trying to greet another species and understand its background? This is the premise of Fathom, a new documentary by director Drew Xanthopoulos, known for directing The Sensitives, which explored the lives of people who are debilitatingly sensitive to our world. Fathom follows biologist Ellen Garland at the University of St Andrews, UK, and marine acoustician Michelle Fournet at Cornell University in Ithaca, New York, on their respective studies into humpback whale songs and social communication. While Fournet analyses different whale calls as she tries to create a conversation between humpbacks to understand their communication better, Garland studies the cultural transmission, vocal learning and function of whale songs. We watch as the two prepare for field studies in Alaska and French Polynesia. Fathom‘s languid pace prevents viewers from completely immersing themselves. Although this leaves you waiting for something to happen, it allows Xanthopoulos to hone in on detail and show marine bioacoustics at its slow work. The scientists use hydrophones to acoustically track whales, capturing different calls, most notably the “whup” call, which Fournet studies. Basing herself in Hobart Bay, Alaska, she is forthcoming about the challenges of surveying 30 whales in a month using focal follows, which involves tracking a specific animal, and playbacks, in which she rebroadcasts natural or synthetic signals to animals and notes their response. Her candour about the likelihood of failure because of logistical complications brings a level-headedness amid the lofty ambitions, and her willingness to adapt her approach to fine-tune the “conversation” shows flexibility.
6-23-21 Can we use nudge theory to help endangered animals save themselves?
Endangered wildlife often doesn't have time to evolve to rapidly changing environments. Now conservationists are manipulating animal behaviour, using "nudge" techniques akin to those designed to influence humans. KEN RAMIREZ is an animal trainer with decades of experience, including a 25-year stint at the Shedd Aquarium in Chicago, Illinois. He has taught all sorts of creatures to do all manner of tricks. Once, he trained thousands of butterflies to perform a choreographed display in a botanical garden. It took several weeks, but even he was impressed with the result. “I watched in awe,” he says. “They appeared to undulate to the rhythm of the music – it was incredible!” These days, however, Ramirez is less likely to use his talents for entertainment. Instead, he is working to protect wild animals by tweaking their behaviour. That may sound intrusive, but, in a rapidly changing world where human activities can have fatal consequences for wildlife, evolution often can’t act fast enough to meet the challenges. So a growing number of conservationists aim to encourage wild animals to adapt by understanding and manipulating behaviours like hunting, foraging, mating and migration. In fact, the approach resembles strategies increasingly adopted by governments and organisations to spur humans towards healthy or socially beneficial choices. Sometimes referred to as “nudges”, these are based on the idea that, for example, we choose to eat more vegetables if we encounter a salad in the buffet line before pizza. Or that scarce parking in a city encourages us to cycle or take the bus. “All creatures learn the same way,” says Ramirez. “Let’s make what we don’t want animals to do difficult and what we want them to do easy. A little nudge can guide them to do the things that are going to save them.”
6-23-21 ‘Fathom’ seeks to unravel humpback whales’ soulful songs
A new film takes viewers deep below the ocean’s surface to hear the eerie chorus of whale calls. In an opening scene of the new film Fathom, Michelle Fournet sits at her computer in the dark, headphones on. The marine ecologist at Cornell University is listening to a humpback whale song, her fingers bobbing like a conductor’s to each otherworldly croak and whine. Software converts crooning whale sounds into the visual space of craggy valleys and tall peaks, offering a glimpse at a language millions of years in the making. Debuting June 25 on Apple TV+, Fathom follows two scientific teams studying the enigmatic songs of humpbacks. The film captivates, diving into the quest to unveil the inner world of these animals and their ever-changing song culture — one considered far older than our ancestors’ first upright steps. On opposite sides of the Pacific Ocean, scientists head out onto the water. In a mountain-fringed bay in Alaska, Fournet makes repeated attempts to talk to the whales, playing them a painstakingly reconstructed rendition of a yelp that she thinks may be a greeting. In French Polynesia, behavioral ecologist Ellen Garland of the University of St. Andrews in Scotland listens to humpback songs, mapping how they are tweaked, learned and shared by whales across the South Pacific. These settings are stark and gorgeous, their isolation artfully shown through silent, foggy mornings and endless cobalt seas. In a film fundamentally about oceans filled with sound, ample quiet rests on the surface. Directed by Drew Xanthopoulos, Fathom portrays humpbacks and other whales as complex, highly social beings without overstated anthropomorphism. In one goose bump–inducing scene, Garland’s narration identifies whales’ social similarities to humans, but set in a totally different environment. Perceiving each other chiefly with sound cast over stupefying distances, “whales evolved to build relationships in the dark,” Garland says.
6-23-21 Elephants' 500km-trek across China baffles scientists
Elephants are by nature fiercely intelligent beasts and experts who study them day in day out already know a great deal about them. And yet a herd of endangered elephants in China has completely dumbfounded scientists globally, while captivating an entire nation in the process. It's not unusual for elephants to move small distances. But this herd has been lumbering its way across China for more than a year now. The elephants have now strayed almost 500km (310 miles), a mammoth trek from their original habitat. It's thought that they started their journey last spring from Xishuangbanna National Nature Reserve in the southwest of the country, near the border with Myanmar and Laos. They began moving north and in the last few months, the elephants have popped up in a number of villages, towns and cities. They've been seen smashing down doors, raiding shops, "stealing" food, playing around in the mud, taking a bath in a canal and napping in the middle of a forest. They've also been spotted hoovering up crops in their wake and moseying into people's houses - on one occasion, lining up in a courtyard to drink water, successfully turning on a tap with their trunks. It is thought they have started to move south again, and were last spotted in Shijie - a town near the city of Yuxi. It's unclear whether they are headed back, or why they even embarked on this journey in the first place - the farthest known movement by elephants in the country. Or what might come next. "The truth is, no-one knows. It is almost certainly related to the need for resources - food, water, shelter - and this would make sense given the fact that, in most locations where Asian elephants live in the wild, there is an increase in human disturbances leading to habitat fragmentation, loss and resource reduction," Joshua Plotnik, assistant professor of elephant psychology at Hunter College, City University of New York, told the BBC.
6-22-21 Some geckos can use their tail as a ‘fifth foot’ to cling to walls
Geckos have an extraordinary ability to cling to smooth vertical surfaces thanks to special gripping toe pads. Less well known is that some geckos have another sticky pad underneath the tip of their tails – and a study shows it is comfortably strong enough to support the weight of the animal on its own. Adhesive toe pads are the subject of much scientific interest, says Aaron Griffing at Marquette University in Wisconsin. But the tail pads are considerably less understood, although it is more than 120 years since they were first recognised. “They have been truly mysterious structures for a really long time,” says Griffing. To compare the tail pads to the toe pads, Griffing and his colleagues studied the crested gecko (Correlophus ciliatus), a tree-dwelling gecko in possession of a tail pad that is native to New Caledonia in the Pacific Ocean. The team used high-powered microscopes to view the pads’ microscopic anatomy, finding that the tail pads, like those on the toes, are covered in thousands of branched, hair-like structures called setae that can cling to surfaces through intermolecular attraction. In laboratory experiments, the researchers discovered that a tail pad can support five times the gecko’s body weight – roughly the stickiness of a single gecko toe. This means the crested gecko’s tail can act like another limb, says Griffing, which may be useful in the treetop environment where “having a firm grasp on your environment is quite important”. The researchers also tracked how the tail pad arises during embryonic development. They found that the tail pad grows and changes shape like toe pads do, and it does so at about the same point in the development of the embryo. Griffing thinks that sometime in the gecko’s evolutionary history, the “developmental programming” for toe pads was turned on in the tail tip.
6-22-21 Young eels escape from the mouths of fish by wriggling out the gills
Eels really are slippery customers. Juvenile eels captured by fish can escape by wriggling backwards through the predators’ gills. This unique behaviour, never seen before, has been filmed by Yuuki Kawabata at Nagasaki University in Japan and his colleagues. The researchers originally planned to study the predator escape behaviour of juvenile Japanese eels (Anguilla japonica). However, in the initial experiments, team member Yuha Hasegawa noticed that juvenile eels he had filmed being captured by dark sleeper fish (Odontobutis obscura) were somehow swimming around the aquarium again. So on the next occasions, the team kept the camera running after the eels were captured. The videos reveal the tails of the eels appearing through the gills of the fish. At this point, the fish often respond by swimming vigorously or rubbing against the aquarium wall. Soon afterwards, the rest of the eels’ bodies emerge backwards through the gills. Of 54 eels observed being captured, 28 escaped in this way, and almost all appeared completely unharmed. It isn’t clear whether or not these escapes are fortuitous. Some eels swim backwards rapidly when threatened, and this simple response may allow the young eels to escape. But it could also be a specialised tactic that the eels have evolved, says Kawabata. “Natural selection would favour this behaviour,” he says. Many animals have evolved extraordinary tactics for escaping predators, from producing slime and squirting blood to jumping out of their skins. As far as Kawabata is aware, this is the first time that any prey animal has ever been recorded escaping through the gills of a fish. “No one has reported this behaviour in the past,” he says. In 2006, Fleur Ponton, now at Macquarie University in Australia, and her colleagues reported that the parasitic gordian worm (Paragordius tricuspidatus) can escape from the mouth, nose or gills of fish that eat insects infested with the worms. But this situation is different as the prey of the fish is the insect, not the parasitic worm inside it. Ponton says she hasn’t heard of any other animals escaping predators via their gills.
6-22-21 Snakes know how much venom they have and won't attack if running low
Pit vipers may be able to sense how much venom they have in reserve to deal with a threat, a study suggests. The team housed 23 juvenile snakes in separate boxes, dividing them into three groups defined by venom levels: low, replenishing and normal. The low and normal venom groups followed a three-day testing cycle over 24 days. For the first two days of each cycle, the team enticed individuals in the low venom group to bite into a cloth once each day to ensure they had little venom. The normal venom group experienced a blank test, during which they were gently poked instead. Every third day, all snakes underwent a behavioural trial. The replenishing venom group initially followed the same pattern as the low venom group. But for the final three testing cycles, the researchers gave these snakes four days of respite after each behavioural trial to allow them to replenish their venom. During the behavioural trials, each snake was provoked for a minute using a piece of medical silicone skin at the end of a snake hook. Snakes responded by sounding a warning, fleeing or striking and injecting the silicone skin with venom. Snakes with normal venom reserves performed more strikes overall. Conversely, low-venom snakes showed more fleeing behaviour. The venom-replenishing vipers became more willing to strike in the second half of the experiment, when they were given more time to build up venom reserves. The researchers argue this suggests that the snakes can sense their venom levels and tailor their response to a threat accordingly. “This carefully designed study certainly provides a lot of thought-provoking evidence,” says Arie van der Meijden at the University of Porto, Portugal. However, he cautions that fatigue, habituation or hunger could also be factors in explaining the results.
6-22-21 Tasmanian devils devastate penguin population on Australian island
A project to preserve endangered Tasmanian devils on a small island has backfired after the predators killed seabirds in large numbers, a conservation group says. A small number of devils were shipped to Maria Island east of Tasmania, Australia, in 2012. The move aimed to protect the mammals from a deadly facial cancer that had driven them towards extinction. The devils have recovered since, but the island project has come at a cost. The introduction of the devils to the island has had "a catastrophic impact on one or more bird species", according to BirdLife Tasmania, a local conservation organisation. Citing a government survey, BirdLife Tasmania said a population of little penguins that numbered 3,000 breeding pairs in 2012 had disappeared from the island. "Losing 3,000 pairs of penguins from an island that is a national park that should be a refuge for this species basically is a major blow," said Dr Eric Woehler, a researcher for the group. Dr Woehler said the outcome was no surprise given what research shows about the introduction of mammals to oceanic islands. In 2011, a report by the Tasmanian Department of Primary Industries, Parks, Water and Environment suggested the introduction of devils would have "a negative impact on little penguin and shearwater colonies on Maria Island". Last year, a paper published in the Biological Conservation journal said the devils had "eliminated" a colony of shearwater, a species of sea bird. "It's very clear that the devils have had a catastrophic ecological impact on the bird fauna on Maria Island," Dr Woehler said. The mammals were moved to the island under the Save the Tasmanian Devil Program (STDP), a joint initiative of the Australian and Tasmanian governments. Tasmanian devils are classified as an endangered species by the IUCN Red List, which keeps a database on the conservation status of animals. But Dr Woehler said their numbers had recovered in Tasmania and on the Australian mainland, where devils were born for the first time in thousands of years last month.
6-21-21 New images clarify how glasswing butterflies make their wings transparent
Sparse, spindly scales and a waxy membrane coating are behind the insect’s transparency. Most butterflies sport colorful, eye-catching patterns on their wings. But some species, like the glasswing butterfly, use mostly transparent wings to hide in plain sight. To figure out how these Central American butterflies go incognito, researchers put the wings of glasswing butterflies (Greta oto) under the microscope. Sparse, spindly scales overlaying a see-through wing membrane with antireflective properties help make these insects so stealthy, researchers report in the May issue of the Journal of Experimental Biology. Transparency is the ultimate form of camouflage, says James Barnett, a behavioral ecologist at McMaster University in Hamilton, Canada, who wasn’t involved in the work. Transparent animals can instantly blend into any background (SN: 6/5/19). “It’s really hard to do,” Barnett says. “You have to modify your entire body to minimize any scattering or reflection of light.” Aaron Pomerantz, a biologist at the University of California, Berkeley, became fascinated by butterflies with transparent wings while doing research in Peru. “They were really interesting and mysterious,” he recalls, “like these little, invisible jets that glide around in the rainforest.” Using confocal and electron microscopes, Pomerantz and colleagues found that the black rims of G. oto’s wings were densely packed with flat, leaflike scales. But the transparent areas sported narrow, bristle-like scales spaced farther apart. As a result, only about 2 percent of the underlying clear wing membrane was visible in black regions, but about 80 percent of the membrane was exposed in transparent areas. “You’d think the simplest solution would be to just not have any scales,” says coauthor Nipam Patel, a biologist at the Marine Biological Laboratory in Woods Hole, Mass. But butterflies need at least some scales in the transparent parts of their wings: The water-repellant scales help prevent the wings from sticking together when it rains, he says.
6-20-21 'World's oldest' alligator Muja celebrates 85th birthday at Belgrade Zoo
From surviving World War Two to becoming a hit on TikTok, Muja the alligator has been through a lot. The 85-year-old reptile at Belgrade Zoo in Serbia is believed to be the world's oldest alligator.
6-18-21 'Living fossil' fish may live for up to a century
A "living fossil" fish can live for an impressively long time - perhaps for up to a century, according to a new study. The coelacanth was thought to have a life span of around 20 years, but new estimates suggest it is a centenarian of the ocean, alongside sharks. French researchers studied marks on the scales of museum specimens - much like tree rings tell the age of trees. They believe the fish reproduces only in late middle age and can be pregnant for as long as five years. Slow-growing fish that produce few young are particularly vulnerable to extinction pressures, such as climate change and overfishing. Knowing the coelacanth's life history might help to enforce even stronger protection and conservation measures, said Dr Bruno Ernande of the University of Montpellier, France. "One very important framework for conservation measures is to be able to assess the demography of the species," he told BBC News. "With this new information we will be better able to assess it." The coelacanth was long thought to have gone extinct until famously turning up in a fishing net off South Africa in 1938. Two populations were subsequently discovered living off the eastern coast of Africa and another off the coast of Sulawesi, Indonesia. The African population is classed as critically endangered, with possibly only a few hundred individuals left. "[The] coelacanth appears to have one of, if not the slowest, life histories among marine fish, and close to those of deep-sea sharks and roughies," said Kélig Mahé of the North Sea Fisheries Research Unit in Boulogne-sur-mer, France. "Our results thus suggest that it may be even more threatened than expected due to its peculiar life history. Consequently, these new pieces of information on coelacanths' biology and life history are essential to the conservation and management of this species."
6-17-21 Thousandth dormouse brought back to the wild
The 1,000th captive-bred hazel dormouse has been released into the wild in a UK-wide reintroduction scheme for these threatened mammals. Big-eyed and famously sleepy, the dormouse is a woodland and fairy tale icon, but it is a species in decline. Once widespread, the animals have now disappeared from 17 English counties. Reintroduction, scientists say, is the only way to bring dormice back to habitats from which they have been lost. The project, a collaboration between the wildlife charity People's Trust for Endangered Species (PTES), Natural England and the University of Cumbria, brought 15 breeding pairs to a secret location in the Arnside and Silverdale Area of Outstanding Natural Beauty in Lancashire. "When I started 15 years ago, there were five populations in northern England, and now there's only one," said Ian White, who has worked for the PTES for 15 years. "It's a decline in woodland and hedgerow management. Dormice live in the shrub layer of woodland, and in many areas that layer has been stripped out, or the forest has been left to grow up and shade out the understory." With its tangle of hazel, willow and bramble, the chosen Lancashire release site is ideal for the rodents, but getting them there has been a time-consuming team effort. The 30 dormice in this most recent (and most northerly) release were bred and reared in captivity at London Zoo. They were kept in quarantine for nine weeks and thoroughly checked for disease or parasites, before being transported more than 250 miles by car. The animals travelled in special dormouse nest boxes that were handmade by prisoners in HMP Doncaster and Humber - as part of a partnership between the PTES and the Department of Justice. "Dormice belong here," said Dr Deborah Brady, from the University of Cumbria in Ambleside. "But 50% of the population has been lost in just the last 20 years, which fits in with the loss of biodiversity we're facing more broadly.
6-16-21 How gardeners can help plant-eating insects instead of killing them
AS MOST of the UK recovers from a frigid April and a soggy May, its gardens are starting to perk up. That means so are caterpillars, aphids such as greenflies, and other plant-feeding invertebrates generally seen as the gardener’s foes. A common reaction to seeing prized plants covered with bugs is to reach for the pesticide spray. But we should temper that instinct, says Andrew Salisbury, principal entomologist at the UK Royal Horticultural Society. Many invertebrate species in the UK and elsewhere are in decline, and gardens can be a haven – the UK’s home gardens collectively add up to an area larger than the country’s official nature reserves. You might think there is no shortage of aphids, but they are food for bigger insects, such as ladybirds, lacewings and wasps, not to mention blue tits. While gardens are a much understudied ecological resource, some work suggests they can support hundreds of invertebrate species, including at least two insects in decline in the UK: two-spot ladybirds and, in the south, stag beetles. Most synthetic pesticides kill aphids’ insect predators too – and aphids tend to bounce back faster than their predators, requiring repeated spraying. If you must spray, try to use organic, soap-based products, which tend to be less harmful to predators – though they aren’t completely non-toxic, says Salisbury. He doesn’t advise home-made soap solutions as they haven’t been tested for their effects on plants or wildlife. There are other ways you can encourage invertebrates into your garden, according to a four-year study by Salisbury and his team. These include denser planting (although spiders love bare spots between plants) and choosing British species. The researchers compared how many invertebrates could be supported by three types of typical garden planting scheme: native British plants, “near-native” plants (defined as those from the same genus found in the northern hemisphere) and exotics, or those from the southern hemisphere.
6-16-21 Seagull eggs in the UK have been contaminated with plastic additives
Seagull eggs have been found to be contaminated with chemical additives used in plastic production. A study looked for evidence of phthalates – a group of chemicals added to plastics to keep them flexible – in newly laid herring gull eggs in Cornwall, UK. All 13 eggs that were tested were found to contain phthalates, with up to six types of phthalate per egg. These chemicals function as pro-oxidants – potentially causing oxidative stress that can damage cells. “Herring gull mothers pass on vital nutrients to their offspring via their eggs,” said study author Jon Blount at the University of Exeter, UK. “This includes lipids that nourish developing embryos, and vitamin E, which helps to protect chicks from oxidative stress that can occur during development and at hatching. “Unfortunately, our findings suggest that mothers are inadvertently passing on phthalates and products of lipid damage – and eggs with higher phthalate contamination also contained greater amounts of lipid damage and less vitamin E.” The researchers say the impact of their findings on developing chicks isn’t yet known, and further research is needed. Phthalates – which are used in most plastic products and readily leach out – can build up in living organisms by becoming concentrated in fatty tissues. While the study doesn’t show where the gulls acquired the phthalates, they have been previously found in species preyed on by herring gulls, and the birds are known to swallow plastic. “Research on the impact of plastic on animals has largely focused on entanglement and ingestion of plastic fragments,” said Blount. “Far less is known about the impacts of plastic additives on the body. “By testing eggs, our study gives us a snapshot of the mother’s health – and it appears phthalate contamination could be associated with increased oxidative stress, and mothers transfer this cost to their offspring via the egg,” he said.
6-15-21 Secrets of tiny diving mammals revealed
Biologists have uncovered the genetic secrets of the world's smallest diving mammals - water shrews. Using DNA samples to construct an evolutionary tree, scientists revealed that diving behaviour evolved five distinct times in this group of insect-eating mammals. The ability of these tiny, warm-blooded animals to dive and hunt in freezing water seems to defy evolutionary logic. The findings are published in the online journal eLife. To track this surprising evolutionary journey, the scientists collected DNA samples from 71 different species all belonging to a large group of related, insect-eating mammals, collectively called Eulipotyphla. That Greek term translates to "the truly fat and blind"; it is a group of mammals that includes hedgehogs, moles and shrews. "We sample specimens from all over the world," said lead researcher Dr Michael Berenbrink, from the University of Liverpool. Once he and his colleagues had created their Eulipotyphla family tree - building the genetic code into a detailed picture of the relationship between each species - they were able to use that information to track the evolution of diving behaviour. "We mapped the evolution of a single protein, called myoglobin, that stores oxygen in the muscle," explained Dr Berenbrink. "We can see a genetic signature [in the DNA] that shows us when this key protein increased in abundance in the animals' muscles." He explained that this is the change needed for an animal to store more oxygen in its muscles, so it can hold its breath under water and hunt. That "diving signature" occurred five distinct times in this group of animals. "It evolved three times in the shrews and twice in the moles," Dr Berenbrink added. "The genetic sequence of just one protein tells us so much about the lifestyle of these animals that we couldn't figure out from fossils."
6-15-21 As ‘phantom rivers’ roar, birds and bats change their hunting habits
A massive experiment in the Idaho wilderness shows how natural noises can impact ecosystems. For two summers in a rugged corner of Idaho’s Pioneer Mountains, the roar of rushing whitewater filled the air. But where the loud sounds prevailed, only gentle streams flowed by. These phantom rivers were part of an experiment led by ecologist Dylan Gomes of Boise State University. He and colleagues were testing a hypothesis that the sounds of nature influence where animals lived and how they forage. “There’s a lot of research suggesting that [human] noise negatively affects [animals], from communication to foraging to reproduction, and even survival,” Gomes says. For example, the sounds of highway traffic can drive migrating birds away from their regular rest stops (SN: 2/9/15). But the natural soundscape is “one component of the niche that we’ve been ignoring,” says Gail Patricelli, an ecologist at the University of California, Davis who was not involved in the study. The phantom rivers experiment suggests we shouldn’t, she says. Gomes and his team hauled about 3.5 metric tons of speakers, solar panels and other equipment into the countryside. Though they carried most of this gear on their backs, the researchers had to call on a mule train when an access road flooded during the first summer. At 60 study sites near streams, the researchers broadcast whitewater noise at different volumes and frequencies, or pitches, creating the auditory illusion of rushing rivers. As the phantom rivers played, the researchers surveyed two prevalent, sound-dependent animal groups — birds and bats. Bats echolocate and listen for their prey, and birds communicate through song, Gomes explains. “They’re such sound specialists that it makes sense to focus on them.”
6-14-21 Fox-breeding experiment suggests domestication can boost brain size
Our understanding of how domestication changes the neurobiology of a species may be wrong, results from a 60-year experiment to breed tame foxes suggest. The findings could also have implications for human evolution, claim researchers. Usually, domesticated animals have smaller brains than their wild counterparts, but foxes raised in a Russian fox farm experiment in Novosibirsk haven’t followed that trend. On the contrary, fox lines purposefully bred for either a good or a bad relationship with humans had larger brains than those that weren’t, says Erin Hecht at Harvard University, who is part of a team studying specimens from the experiment. The unexpected findings “suggest revision of existing thinking about domestication”, perhaps towards an idea that brains respond to behaviour-related pressure, at least initially, by developing more grey matter, says Hecht. Starting in 1959, project scientists began selectively breeding silver foxes (Vulpes vulpes) in a fur farm. With each generation, they chose the tamest animals to reproduce together, while also choosing the most aggressive animals to reproduce together. The researchers left a third group of foxes to mate without selection for behavioural aspects, as a control. The idea, researchers said at the time, was to create a model of the animal domestication process. The project has led to dozens of published papers but has also seen criticism for developing captive animals that are fearful of humans. Now, an international team of researchers has examined the brains of 30 males from recent generations of those foxes. The group took the preserved left hemispheres of the brains of 18-month-old foxes and examined them under high-resolution magnetic resonance imaging (MRI). Surprisingly, the third group – the control foxes – actually had the smallest brains, says Hecht. Equally surprising, the “tame” fox brains were, on average, nearly identical in size and structure to the “aggressive” fox brains. In particular, the team noted that both tame and aggressive foxes had similar kinds of changes in the same parts of the brain that are apparently associated with tameness in dogs compared with wolves, including the prefrontal cortex, hippocampus and amygdala.
6-14-21 Female seahorses cheat on their mate when they can no longer smell him
Monogamous female seahorses cheat on their male partners when they can’t smell them any more. “Seahorses can express incredible loyalty and affection once a pair has bonded during the reproductive season,” says Dong Zhang at the Chinese Academy of Fishery Sciences in Shanghai. The curvy-tailed couples usually stay together for months or years. They live within a few metres of each other and meet up at daylight for “morning greetings” that reinforce their bond – swimming in parallel, brightening their hues and “dancing”, says Zhang. They reproduce through male pregnancy after the female deposits her eggs into the male’s abdominal brood pouch. The couple takes a mating break during the 12 to 20 days the male is pregnant, but then they mate again within 48 hours after he gives birth. Zhang and his team wondered what kept the female faithful during the waiting time and how she distinguished her mate from other males. They tested 200 pairs of virgin, lab-raised lined seahorses (Hippocampus erectus) in various situations. They allowed them to couple up, placing a female and her pregnant mate in a tank with a second male that had just given birth, which may have made him more attractive because he had proven to be fertile, says Zhang. Then they placed the pregnant mate either in a mesh cage, an opaque open-ended pipe or a transparent plastic bag. These barriers respectively blocked morning greetings, vision or odours. After the mate gave birth, the researchers let all three seahorses swim freely. If a female hadn’t been able to see or greet her mate during pregnancy, she still chose him over the other male, except for a few rare cases in which a female didn’t choose either male, says Zhang. However, 75 per cent of the females that hadn’t been able to smell their enclosed mates chose the other male. It is possible that while the mate was in the transparent bag, the female forgot his scent and got used to the other male’s odours, says Zhang.
6-14-21 ‘Really, really rare’ seahorse spotted off UK coast
A long-snouted seahorse has been photographed off the coast of Plymouth, south west UK. Also known as a spiny seahorse, the protected marine animal can be found in shallow waters among seagrass meadows, though a licence is needed to look for them. Diver Mark Parry from the Ocean Conservation Trust recounts his sighting.
6-13-21 Swiss voting in pesticide ban referendum
Swiss citizens are voting in a referendum which could see their country become only the second in the world to ban synthetic pesticides. One initiative proposes to end subsidies to farmers who use such pesticides, while another one would ban them altogether within 10 years. Supporters point to worrying levels of pesticides in water, and damage to plants, animals and insects. But Swiss farmers warn the proposals will put many of them out of business. Pesticides are chemical or biological agents used to control pests. Voting is also taking place on Sunday on other initiatives: anti-terrorism legislation, a new tax on fossil fuels and emergency Covid-19 funding. Switzerland's system of direct democracy means all major decisions in the Alpine nation are taken at the ballot box. Campaigners simply have to gather 100,000 signatures to ensure a nationwide vote. If approved, the pesticide initiatives would go much further than the handful of towns and regions around the world that have already banned all synthetic pesticides. It would also be of greater global significance than the ban imposed by Bhutan in 2013, as Switzerland is the home of the world's biggest pesticide manufacturer, Syngenta. "I'm going to vote 'Yes' - we have to think about the future. Pesticides damage our health," Geneva resident Marie Lenbaus said. Both proposals are widely backed by young urban voters. But Swiss farmers say they are already complying with some of the strictest rules in Europe. They have seen their jobs and income decline over the last 20 years, and now they are furious, the BBC's Imogen Foulkes in Bern reports. "You find a lot of people, especially in the cities, they have not even a clue what farming means," said Martin Haab, president of Zurich Farmers Association. "So, if they have two tomatoes in their garden in front of the window, they think they understand farming and they know how to do organic farming," he said.
6-12-21 Mouse sperm thrived despite six years of exposure to space radiation
The findings suggest that long-term space travelers may still give birth to healthy children. Sperm appears to be unfazed by long stints in outer space. In the longest biological experiment on the International Space Station yet, freeze-dried mouse sperm remained viable after nearly six years in space. Exposure to space radiation didn’t seem to harm the sperm’s DNA or the cells’ ability to produce healthy “space pups,” researchers report online June 11 in Science Advances. That may be good news for future spacefarers. Scientists have worried that chronic exposure to space radiation might not only put astronauts at risk for cancer and other diseases, but also create mutations in their DNA that could be passed down to future generations (SN: 9/25/20). The new results hint that deep-space travelers could safely bear children. Studying how space radiation affects reproduction is tricky. Instruments on Earth can’t perfectly mimic space radiation, and the ISS lacks freezers for long-term cell storage. So biologist Teruhiko Wakayama of the University of Yamanashi in Kofu, Japan and colleagues freeze-dried sperm, allowing it to be stored at room temperature. The team then sent sperm from 12 mice to the space station, while keeping other sperm from the same mice on the ground. After returning the sperm cells to Earth, rehydrating them and injecting them into fresh mouse eggs, the team transferred those embryos to female mice. About 240 healthy space pups were born from sperm kept on the ISS for nearly three years; about 170 others were born from sperm kept on the space station for nearly six years. Genetic analyses revealed no differences between these space pups and mice born from sperm stored on the ground. Space pups that mated as adults had healthy children and grandchildren.
6-11-21 Backlash against 'frightening' tests on whales
An international group of scientists has called on Norway to halt plans for acoustic experiments on minke whales. They say the process of capturing the animals and subjecting them to noise will be "stressful and frightening". The project, the largest of its kind ever attempted, is due to begin any day now. The Norwegian authorities say the aim is to get a better understanding of the levels of noise pollution that whales can hear. The experiments will take place in the remote Lofoten Islands. The goal is to use huge nets to drive 12 young minke whales into a holding pen - and local observers have confirmed that everything seems ready. According to the Norwegian Food Safety Authority, the official body that's authorised the project, each whale will be held for up to six hours. They will undergo blood tests and have electrodes fitted under their skin to measure their hearing. "If necessary," the statement says, "the whales will be sedated". But the authority says that based on the evidence of what happens when minke whales are caught in nets, it expects the animals to "lie completely still" until they are released. It says, "there is no question of exposing them to loud noise but of finding the lowest noise that they can actually hear". Before being freed, the whales will have satellite tags fitted to their dorsal fins so their behaviour after the experiments can be monitored. It is officially acknowledged that the whales will experience pain, particularly while they are held between two rafts while their hearing is tested. The Norwegian Food Safety Authority judges that the severity of the experiment will be "moderate" and it defines what that means: "Animals are likely to experience short-term moderate pain, suffering or distress, or long-lasting mild pain, suffering or distress," it said. It also said that "moderately severe" experiments of this kind "are likely to cause moderate impairment of the well-being or general condition of the animals". But it concludes that by learning more about how noise pollution disturbs marine animals, the research will benefit minke whales and other species - so it should go ahead.
6-11-21 The deep sea hosts twice as many shapes of fish as shallow waters
With eels that have heads shaped like tweezers and anglerfish that look like swimming light bulbs, the deep sea is host to a strange menagerie of fish body forms. The alien conditions at the bottom of the ocean may be the cause, making the dark depths a hotspot of body-shape evolution. Previous research has shown that fish metabolism, muscle enzymes and swimming strength decreased with depth, says Christopher Martinez at the University of California, Davis. But there has been no comprehensive comparison of the shapes that fish bodies take at different ocean depths. Martinez and his colleagues were part of an effort to unveil environmental patterns in fish evolution, in which researchers measured the physical proportions of about 6000 fish species in the collections at the Smithsonian National Museum of Natural History in Washington DC. Using this vast new database, Martinez’s team compared the body shapes of more than 3000 fish species that come from habitats ranging from surface waters to the abyss. The team found that fish in the deep sea are nearly twice as diverse as shallow water fish when it comes to body shape. There are many more species in the shallows, but so much of that diversity is concentrated in fish with spindle-like shapes, such as tuna, or those with more compressed shapes, such as butterfly fish. Martinez suggests this is because the turbulent, light-rich environment closer to the surface is full of active prey and predators, which creates an evolutionary pressure to develop a strong, manoeuvrable body. This funnels shallow water fish into a handful of streamlined shapes. In the slow, quiet deep, athleticism isn’t as important for survival, he says. Released from the constraints of natural selection, surreal proportions emerge.
6-9-21 The mere sight of illness may kick-start a canary’s immune system
Simply seeing another bird get sick is enough to trigger an immune response in healthy birds. For canaries, just seeing their feathered friends get sick may be enough to preemptively rev up their immune systems. Healthy birds housed within view of fellow fowl infected with a common pathogen mounted an immune response, despite not being infected themselves, researchers report online June 9 in Biology Letters. “It’s fascinating that some sort of visual cue could alter immune function,” says Ashley Love, a disease ecologist at the University of Connecticut in Storrs. Precisely how much these alterations actually protect the birds remains unclear, she says. Immune systems are like sentinels, patrolling the body for invaders and calling in the cavalry once a pathogen is detected. Traditionally, pathogens have to actually get into bodies to spur that sort of response. But some research has previously hinted that perceived threats can whip up immune cells. For example, one experiment in humans found that a mere photo of a sick person increases the activity of inflammation-stimulating chemicals called cytokines. But no one had ever looked to see whether being within eyeshot of an actually sick individual could compel the immune system to preemptive action, Love says. “A lot of wildlife diseases have these obvious physical symptoms,” she says. If wild animals can prepare, immunologically, at the first sign they might become infected, they may be better equipped to fight off the invader once it comes. To test this idea, Love and her colleagues infected 10 caged canaries (Serinus canaria domestica) with Mycoplasma gallisepticum, or MG, a common bacterial pathogen that causes conjunctivitis and extreme lethargy. Sick birds look “pretty fluffed out,” Love says.
6-9-21 Australia whales: ‘Unbelievable’ super-group caught on film
When a drone pilot captured footage of an enormous group of whales off the New South Wales coast last year, it sent scientists into a frenzy. A pod of that size - known as a super-group - and the "bubble-net" feeding behaviour they were displaying had never been documented off Australia before. A research paper has now confirmed both extraordinary events.
6-9-21 Sweet dreams! Wandering elephants take a snooze
A herd of 15 elephants that has travelled 500km has been spotted having a nap in a forest. In recent months the group of Asian Elephants has travelled through many villages, towns and cities in south west China, captivating the county. It remains unknown why the animals decided to leave home. Authorities are tracking their movements.
6-8-21 Cattle that spend more time around humans have smaller brains
The average brain size of cattle has shrunk as we have domesticated them, and their brains seem to get smaller the more time they spend around humans. In general, domesticated animals tend to have smaller brains than their wild counterparts. This phenomenon hadn’t previously been identified in cattle, as their wild ancestor has been extinct for several hundred years. To estimate the brain size of wild cattle, Ana Balcarcel and her colleagues at the University of Zurich in Switzerland measured 13 skulls from the extinct aurochs (Bos primigenius), the probable ancestor of modern cattle. They then compared these to known measurements of 317 skulls from 71 breeds of domestic cattle (Bos taurus). Based on the size differences in the skulls, the team estimates that the brains of domestic cattle are about 26 per cent smaller on average than those of wild cattle. “Really, the surprising result was that when we compared not just the wild versus domestic, but all the different breeds within the domestic populations, we found differences there,” says Balcarcel. “Those differences correlate strongly with the amount of time these animals spend with humans. The intensity of the human contact really has an effect on how much the brain reduces.” The team found that cattle that are around humans more often, such as dairy cows, have the smallest brains, while bullfighting cattle that only have limited contact with humans had larger brains, closest to the size of their wild ancestors. Breeding cattle to be more docile seems to be driving these changes in brain size, says Balcarcel. Dominic Wright at Linköping University in Sweden says this may be an overly simple explanation. “There does seem to be a shift in relative brain size from the wild to the domestic,” he says. “The problem is, we don’t know if modern cattle definitely came from these aurochs, which [this team] happens to be using in their study, but it seems like there’s a good possibility that they are representative of their wild progenitors.”
6-8-21 Whale that travelled halfway around the world sets migration record
Between May and July of 2013, a single grey whale (Eschrichtius robustus) was spotted off the coast of Namibia. This was odd, as while there have been rare sightings of this species in the Atlantic Ocean, they are usually confined to the northern hemisphere. t turns out the animal had travelled at least 20,000 kilometres – halfway around the planet – setting a record for a migration of any mammal, barring humans. Rus Hoelzel at Durham University in the UK and his colleagues used tissue samples collected from the whale’s skin and analysed its DNA to trace its origins. By comparing it with other grey whale populations, they found that this individual, a male, was probably born to the endangered western North Pacific population, found along the coast of eastern Asia. This means it travelled at least 20,000 kilometres to get to the southern Atlantic. Earth’s circumference is slightly over 40,000 kilometres. “This is the record really for an in-water migration, if you’re assuming that this individual started its life in the north-west Pacific and it found its way to Namibia,” says Hoelzel. “That’s as far as any vertebrate has ever gone in water, as far as we know.” Land dwelling mammals fall far short of this feat – the record is a grey wolf that roamed more than 7000 kilometres in a year. While it is impossible to know for sure how this whale got to the southern Atlantic, the team has proposed three possible routes – it could have headed north through the Arctic, south around South America, or along Asia and around Africa. “At the population level, what’s interesting is that we are seeing a lot of changes in the environment that have to do, in this particular case, with the opening up of the Arctic Ocean due to climate,” says Daniel Palacios at Oregon State University. “It goes beyond this one animal to potentially many animals doing the same thing.”
6-8-21 A single honeybee has cloned itself hundreds of millions of times
The workers of a South African subspecies of honeybee can clone themselves, with one individual having done so many millions of times over the past 30 years. Some of the clones can even develop into queens that can take over the hive. Asexual reproduction – parthenogenesis – isn’t uncommon in the insect world, but having offspring that are genetically identical to the parent is. That’s because, during the reproductive process, genetic material gets mixed up in a process called recombination. As a result, even if there is only one parent its offspring end up with a slightly different genetic makeup. However, the female workers of the Cape honeybee (Apis mellifera capensis), native to southern South Africa, have developed the unusual ability to clone themselves while effectively avoiding recombination during reproduction, says Benjamin Oldroyd at the University of Sydney. Doing so carries important benefits. Normally, asexual reproduction can be lethal in honeybees because about a third of the genes become inbred, and the larvae don’t survive, Oldroyd says. But because Cape honeybee worker bees perfectly clone themselves, each clone remains as genetically healthy as her mother. “It’s quite remarkable,” he says. One line of clones has been re-cloning since 1990, with the same individual copied hundreds of millions of times, says Oldroyd. The clones can prove problematic for the health of the colony, however. Generally speaking, the queen bee is the only individual that reproduces, while other bees carry out their own duties to keep the colony healthy. If the workers begin cloning themselves – which can happen if the hive is disturbed in some way – this delicate balance is destroyed. In some cases, one of the clones can even develop into a queen of a dysfunctional hive.
6-8-21 Bdelloid rotifer survives 24,000 years frozen in Siberia
A microscopic multi-celled organism has returned to life after being frozen for 24,000 years in Siberia, according to new research. Scientists dug up the animal known as a bdelloid rotifer from the Alayeza River in the Russian Arctic. Once thawed, it was able to reproduce asexually, after spending millennia in a state of frozen animation known as crytobiosis. Previous research said they could survive frozen for up to 10 years. But the new study, published in Current Biology on Monday, suggested they could last for thousands of years, if not indefinitely. "The takeaway is that a multicellular organism can be frozen and stored as such for thousands of years and then return back to life - a dream of many fiction writers," Stas Malavin, of Russia's Institute of Physicochemical and Biological Problems in Soil Science, told the Press Association. He said more research was needed to see how it achieved the feat. The scientists in the study froze and thawed dozens of the animals in a laboratory to examine the process. Radiocarbon dating aged the bdelloid rotifer specimen at between 23,960 and 24,485 years old. Bdelloid rotifers are a class of rotifer found in freshwater environments around the world. The name rotifer comes from the Latin meaning "wheel bearer". The creatures are known for their ability to withstand extremes. They are one of the Earth's most radioactive-resistant animals, according to the New York Times, which reports they can also withstand low oxygen, starvation, high acidity and years of dehydration. There are reports of other multi-celled organisms coming back to life after thousands of years, including a nematode worm, as well as some plants and mosses.
6-7-21 Tiny animal revived after 24,000 years entombed in Siberian permafrost
A tiny animal called a rotifer has been revived after spending 24,000 years frozen in permafrost. It is the longest a rotifer has been observed to survive in such extreme cold. While simple organisms like bacteria can often survive millennia in permafrost, “this is an animal with a nervous system and brain and everything”, says Stas Malavin at the Pushchino Scientific Center for Biological Research RAS in Russia. It isn’t quite a record – nematode worms have purportedly been revived from permafrost after 30,000 years – but no rotifer has been known to endure for so long. Malavin and his team drilled into permafrost near the Alazeya river in north-east Siberia, Russia, in 2015. They found a single rotifer, a worm-like creature less than a quarter of a millimetre long. When the researchers warmed it up and gave it food, it became active. It also reproduced, because it is a bdelloid rotifer that can clone itself without the need for a sexual partner. “We are quite confident that this is a new species for science,” says Malavin. He and his team sequenced the rotifer’s genome and found it was most similar to a species called Adineta vaga, which is thought to include multiple subspecies that haven’t been properly identified. The researchers used accelerator mass spectrometry to date organic remains that were found with the rotifer. They were between 23,960 and 24,485 years old, suggesting the rotifer was frozen into the permafrost at the same time. Modern rotifers seem to have a similar ability to survive being frozen. Malavin’s team froze individuals from different modern species, as well as some of the offspring of the ancient rotifer, at -15°C for a week. Both groups were equally freeze-tolerant, with similar survival rates.
6-7-21 Water voles released in Yorkshire in boost to endangered species
Water voles are being released at a site in Yorkshire, UK, as part of the second phase of a nature scheme to help the endangered mammals. Some 100 water voles will be released in Timble Ings Woods in the Washburn valley, part of the Nidderdale Area of Outstanding Natural Beauty (AONB), from 8 June, following a release of the same number last September. Yorkshire Water, which is running the scheme, said surveys suggest the 100 voles brought into the site last year have become established in the woodland, with feeding signs, latrines and burrows all spotted. Evidence of water voles has been found up to 500 metres from the original release site, suggesting they are settling into their new home, the water company said. The aquatic mammals, immortalised as Ratty in the classic children’s book The Wind in the Willows, live along slow-flowing rivers, ditches, dykes and lakes with plenty of vegetation, making extensive burrows in the banks. They have suffered steep declines in recent years as a result of being preyed on by invasive American mink, as well as loss and degradation of their habitat and water pollution, and have been identified as a key species for conservation in the Nidderdale area. “We’re pleased to see evidence the water voles we released in September have settled into their habitat, with piles of nibbled grass and stems, as well as droppings spotted recently,” said Lee Pitcher, head of partnerships at Yorkshire Water. “Now they are established, we’re now moving onto the next stage – a second release in the area to further boost the population.” “We also have plans in place to extend the habitat available for the water voles later this year, with new ponds set to be created, which will allow the population to continue to expand and take advantage of the perfect habitat Timble Ings Woods provides these creatures,” said Pitcher.
6-7-21 These ferns may be the first plants known to share work like ants
The plants may form a type of communal lifestyle never seen outside of the animal kingdom. High in the forest canopy, a mass of strange ferns grips a tree trunk, looking like a giant tangle of floppy, viridescent antlers. Below these fork-leaved fronds and closer into the core of the lush knot are brown, disc-shaped plants. These, too, are ferns of the very same species. The ferns — and possibly similar plants — may form a type of complex, interdependent society previously considered limited to animals like ants and termites, researchers report online May 14 in Ecology. Kevin Burns, a biologist at Victoria University of Wellington in New Zealand, first became familiar with the ferns while conducting fieldwork on Lord Howe Island, an isolated island between Australia and New Zealand. He happened to take note of the local epiphytes — plants that grow upon other plants — and one species particularly caught his attention: the staghorn fern (Platycerium bifurcatum), also native to parts of mainland Australia and Indonesia. “I realized, God, you know, they never occur alone,” says Burns, noting that some of the larger clusters of ferns were massive clumps made of hundreds of individuals. It was soon clear to Burns that “each one of those individuals was doing a different thing.” He likens the fern colonies to an upside-down umbrella made of plants. Ferns with long, green, waxy “strap” fronds appeared to deflect water to the center of the aggregation, where disc-shaped, brown, spongey “nest” fronds could soak it up. The shrubby apparatus reminded Burns of a termite mound, with a communal store of resources and the segregation of different jobs in the colony. Scientists call these types of cooperative groups, where overlapping generations live together and form castes to divide labor and reproductive roles, “eusocial.” The term has been used to describe certain insect and crustacean societies, along with two mole rat species as the only mammalian examples (SN: 10/18/04). Burns wondered if the ferns could also be eusocial.
6-5-21 ‘Hangry’ male fruit flies attack each other if they go without food
If you’ve ever been hangry – so hungry you become angry – you have a little something in common with fruit flies. When these insects don’t get enough to eat, they aggressively lash out at others and some even make a kind of fencing manouevre with their legs to fight with other fruit flies. “Male fruit flies display aggression that they direct towards other fruit flies. They don’t show these behaviours towards females,” says Jennifer Perry at the University of East Anglia in the UK. Perry and her colleagues separated virgin male fruit flies (Drosophila melanogaster) into five groups of between 58 and 74 insects. One group consisted of newly emerged adults that had not fed since their larval stage, while another was made up of flies that were allowed to feed throughout the experiment. The remaining groups were fed and then deprived for periods of 24, 48, or 72 hours. At six to seven days old, pairs of flies from each group were placed together with food and monitored over 5 hours. The team observed the pairs 16 or 32 times over 5 hours to record their behaviour. Flies deprived of food had became increasingly aggressive, which peaked at 24 hours without food. The aggressive flies would lunge at and chase each other or fence with their legs. “I think we can all relate to feeling hangry after periods of food deprivation, and what our study shows is that these feelings extend across even very distantly related animals,” says Perry. “They share lots of genes for their physiology and behaviour with vertebrates, including humans. They’re a good model [for aggression] in that way.” Even animals as seemingly simple as a fruit flies have complex social lives and respond to changes in their environment that affect the costs and benefits of social behaviour like aggression, she says.
6-3-21 Puppies are born with the genetic ability to understand humans
Domestic dogs are born to socialise with people because we bred them that way. Two-month-old puppies can already recognise when people are pointing at objects and will gaze at our faces when they’re spoken to – both signs that dogs have an innate capacity to interact with us through body language. Although individual relationships with people might influence that behaviour, at least 40 per cent of this ability comes from genetics alone, says Emily Bray at the University of Arizona. “Over the course of domestication, from wolf to dog, there’s been a clear selection for these social skills,” she says. “It’s something that’s ingrained in them and that emerges at a really young age even before they’ve had much experience with humans.” Bray and her colleagues tested these types of skills in 375 8-week-old Golden retriever and Labrador puppies that were destined to become service dogs. It was the earliest age they could carry out such experiments because the puppies were only just old enough to be motivated by food rewards, Bray says. The researchers found that pointing at food hidden under a cup helped the puppies to find it nearly 70 per cent of the time. The success rate was that high from the start, meaning they weren’t learning to follow pointing, but already knew to do so, Bray says. In a control test, the puppies couldn’t find food hidden under one of two cups at a rate better than random chance, indicating that they weren’t simply smelling it. Much of the variation in different puppies’ ability to follow finger-pointing is explained by genetics, Bray says. Using statistical analyses based on the puppies’ parents and other relatives, the researchers found that genetic factors were responsible for 43 per cent of these variations.
6-3-21 Right whales born in 1981 grew a metre longer than they do today
Surveillance of right whales in the North Atlantic show that individuals born today will grow to be 1 metre shorter, on average, than whales born in the early 1980s. Joshua Stewart at the National Oceanic and Atmospheric Administration in San Diego, California, and his colleagues have used surveillance data collected from aircraft and drones to investigate how North Atlantic right whales (Eubalaena glacialis) have changed over time. The whales have been monitored consistently for decades, and researchers can identify individuals and know when each was born. Stewart’s team collected 202 length measurements of 129 of the whales born between 1981 and 2019: 133 measurements were taken from aircraft between 2000 and 2002, and 69 measurements were obtained using remotely operated drones between 2016 and 2019. The researchers then paired these length measurements with each whale’s birth year and whether or not the whale and its mother had a history of being entangled with fishing gear. Whales born in 1981 were typically longer as fully grown adults than whales born more recently. The measurements suggest that, on average, for every year after 1981 a given whale was born, its body length was 2.5 centimetres shorter. This corresponds to a 7.3 per cent decline in maximum body length – and means a whale born this year would be expected to reach an adult size a metre shorter than that of a right whale born in 1981. “The whales that are born more recently are growing to sizes that are shorter than we would expect,” says Stewart. Given that North Atlantic right whales are among the most endangered whales in the world, there is detailed individual-level information available on each whale and their entanglement history with fishing gear. “We’re interested in this species in particular because they’re a critically endangered species – there are fewer than 400 left,” says Stewart.
6-3-21 Newly recognized tricks help elephants suck up huge amounts of water
Water moves through a pachyderm’s trunk at the rate of flow of 24 shower heads. Whether or not it’s possible to teach an old elephant new tricks, a 34-year-old pachyderm at Zoo Atlanta has recently taught researchers a thing or two about how elephants suck up food and water with their trunks. For one thing, an elephant doesn’t use its trunk as a simple straw. It can also dilate its nostrils to boost its trunk’s carrying capacity while snorting up water, researchers report online June 2 in the Journal of the Royal Society Interface. And that means it takes fewer snorts than expected to stock up on water that they use to drink and hose themselves down. The surprise finding came courtesy of detailed measurements during feeding time, says Andrew Schulz, a mechanical engineer at the Georgia Tech in Atlanta. Other than aquatic creatures, not many animals other than elephants use a type of suction feeding that doesn’t depend on lung power alone. Elephants are the only living land animals to evolve a long, boneless appendage like a trunk, says Schulz. A septum stretching the length of the trunk separates it into two nostrils. But detailed knowledge of what happens inside that muscular structure during feeding has been sorely lacking. So Schulz and his colleagues worked with zookeepers at Zoo Atlanta to take a peek. Using ultrasound to monitor what was happening inside the trunk during feeding, the researchers put one of the zoo’s African elephants through her paces during the summer of 2018. In some trials, the elephant snorted up volumes of water, which in some cases had bran mixed in. To the researchers’ surprise, says Schulz, the ultrasound revealed that each nostril’s available volume ballooned by as much as 64 percent, up from the trunk’s original capacity of about five liters (although the elephant used only a small fraction of this extra space). Flow rate of water through the trunk averaged about 3.7 liters per second, or the equivalent of the amount of water pouring out of 24 shower heads at once.
6-2-21 World's smallest cephalopod gets set to fertilise her own eggs
THIS dramatic image of a female northern pygmy squid (Idiosepius paradoxus) may make it look like a formidable ocean dweller, but it is in fact a close-up of the world’s smallest cephalopod, a minuscule member of a class of molluscs that includes octopuses and cuttlefish. Measuring between just 5 and 20 millimetres across, these squid are so tiny they can fit on a human thumbnail. This female, seen off the coast of Yamaguchi prefecture in southern Japan, is laying her eggs, a process that can take anywhere between a few minutes and an hour, says photographer Tony Wu. The eggs, however, get fertilised in a rather unusual way. Instead of reproducing by copulation, male pygmy squid attach bundles of sperm called spermatophores onto the bodies of females. The sperm then makes its way to a receptacle in the female’s mouth when she is ready to inseminate her eggs, allowing her to inject a small amount of this through a hole she bites in each egg. Here, the pygmy squid can be seen delicately preparing to lay another egg on a blade of eelgrass before she starts the process of insemination.
6-2-21 Anthropomania review: Our love of animals and how we live with them
IN THE 1980s, Hal Herzog often stuck his finger into the cages of baby snakes to see how often he was bitten. It was part of a test he had devised to measure the agreeableness of garter snakes – and some were definitely more aggressive than others. Herzog, now a psychologist at Western Carolina University in North Carolina, knew he was studying animal personality, but at that time it was controversial. “I did not have the moral fortitude to announce that in scientific journals,” he says. Herzog is the first guest on a new podcast called Anthropomania, which sets out to explore the complex relationship humans have with other living things. For example, personality, the focus of the first episode, was once thought to be unique to humans. Today, it is accepted that animals of the same species living in the same conditions have different characters and behaviours, some bolder and others more fearful, for instance. Herzog says he now wouldn’t hesitate to describe his snake research as a study of personality. The podcast, hosted by science communicators Jay Ingram, Niki Wilson and Erika Siren, is inspired by anthropomorphism, the attribution of human characteristics or behaviours to other species. When it comes to personality, people often apply human traits to animals, with one survey showing that many pet owners consider their animals to have a good sense of humour. “Going overboard on their humanness may give us an unrealistic picture of what they really are,” says Ingram. The show highlights our various motivations for engaging with animals. Aside from research, some people want to domesticate or protect animals, and some collect rare and dangerous species to flaunt their wealth and power. There are many consequences. The demand for exotic pets fuels a multibillion-dollar trafficking industry. And many parts of the world lack animal ownership laws, so animals can be neglected or even become invasive in non-native countries, as in the case of the hippos that escaped from drug lord Pablo Escobar’s private zoo. Many now live in Colombia’s waterways.
6-2-21 Parasitic ants keep evolving to lose their smell and taste genes
To most ants, smell and taste are everything. But some parasitic ant species have lost the genes that drive these senses – a sensory shake-up that may be due to the way they outsource some tasks to host species. Interpreting subtle chemical cues through smell and taste help ants hold their societies together. This “chemoreception” is involved in everything from group foraging to recognising nest mates. But not all species of ant live or interact with each other in the same way. Some ants are social parasites that raid the nests of other, closely related ant species, steal their workers and eventually become dependent upon their captives’ labour. To unveil the evolutionary impacts of this parasitic lifestyle, Erich Bornberg-Bauer at the University of Münster in Germany and his colleagues delved into the insects’ genomes – their full genetic instructions. The researchers analysed the genomes of eight ant species: three parasites, their three host species and two non-host species. The team found that the parasitic ants – Harpagoxenus sublaevis, Temnothorax ravouxi and Temnothorax americanus – had half as many taste receptor genes compared with their hosts and the non-host ants. The parasites had also lost about a quarter of their olfactory genes, which are involved in smell. Greg Pask at Middlebury College in Vermont, who wasn’t involved with the work, says he expected some loss of these receptor genes, but not to the degree revealed in the study. In general, olfactory genes are massively multiplied in ants compared with other insects, implying that they are important for ant survival, he says. Relying on host ants for a range of tasks that involve heavy use of smell and taste may allow these chemoreceptor genes to wane over evolutionary time. “If you don’t have to forage and do a lot of the major work where you need chemosensory activity, then you have no pressure to maintain those genes as functional copies,” says Pask. “It turns out if [an olfactory] gene is broken you can get along fine with that, because the host species is able to take care of [the task].”
6-2-21 This smart shift in pesticide use could let insect populations recover
The world's insects are in trouble – if we start using pesticides to protect plants rather than killing insects it could make a big difference. INSECTS are disappearing. The world has 25 per cent fewer terrestrial insects now than in 1990. This includes those we rely on to pollinate our crops and clean our rivers. If we don’t solve this problem very soon, some species will disappear. There are many causes for the insect decline, but insecticides are a major part of the problem. Those used today are longer lasting and up to 10,000 times more toxic than some that were banned in the 1970s. Adding to the problem is that these pesticides are now applied to crops prophylactically and used whether pests are present or not. Overall, the amount of pesticide applied to the land is decreasing, but this is a grossly misleading statistic. A recent paper found that, between 2005 and 2015, there was a 40 per cent reduction in the amount of pesticide applied to crops measured by weight. But because modern insecticides are so much more toxic, the global toxicity of treated land to pollinating insects has more than doubled in the same period (Science, doi.org/f5vp). Governments and regulating agencies are aware of the problem, and some parts of the world have moved to ban the use of certain insecticides outdoors in an attempt to help bees survive. But the pesticides used instead are just as toxic. One often-touted approach is to use pesticide-free pest control methods. These varied techniques are gathered under the name of integrated pest management (IPM) and have been around for decades. They offer effective crop protection and include methods such as crop rotation and the use of natural predators. But their adoption has been incredibly slow, because spraying pesticides is viewed as an easier option. As a result, IPM methods are unfortunately seldom used today. Neither changing insecticides nor shifting to IPM is a quick fix. We argue instead that we need a subtle shift in focus, away from killing pests and towards protecting crops.
6-2-21 Elephant trunks suck up water at speeds of 540 kilometres per hour
Extreme suction helps elephants hold water and food in their trunks, allowing them to inhale at speeds nearly 30 times the rate at which we exhale air when we sneeze. Elephants use their trunks, which weigh more than 100 kilograms, in a variety of ways: to forage through vegetation for food, to drink and even as a snorkel when wading through deep water. To better understand the trunk in action, Andrew Schulz at the Georgia Institute of Technology and his colleagues filmed a 34-year-old female African savannah elephant (Loxodonta africana) completing a series of tests at a zoo in Atlanta. They filled an aquarium with a certain volume of water and measured how long the elephant spent inhaling water from the tank via its trunk. They then measured the volume of water left in the aquarium after the experiment. The researchers calculated that elephants suck up water with what would be an equivalent air velocity of 150 metres per second. “That is around 30 times the speed of the human sneeze,” says Schulz – when we sneeze, we exhale air with a velocity of 4.5 metres per second. Schulz and his team also estimated the trunk’s capacity by measuring the internal volume of a trunk that came from a 38-year-old African elephant that had been put down because of medical issues. This trunk was a similar size and weight to the trunk of the elephant in the Atlanta zoo. The measurements revealed that the elephant was able to inhale a lot more water than the estimated volume of its relaxed trunk. To work out how this is possible, the researchers used ultrasound imaging to view the inside of the trunk as the elephant inhaled. They found that the elephant was able to dilate its nostrils by 30 per cent, consequently increasing the volume of nasal cavity by 64 per cent. “They use this mechanism to suction water and also store it in the trunk to spray on their body to cool down,” says Schulz.
6-2-21 Even hard-to-kill tardigrades can’t always survive being shot out of a gun
That implies hardy water bears may not withstand crash-landing on a new planet. Tardigrades aren’t completely bulletproof, after all. These microscopic critters, also known as water bears, are practically unkillable (SN: 7/14/17). They can go years without food or water, withstand freezing and scalding temperatures and endure blistering radiation and the vacuum of outer space. But a recent experiment stress tested these death-defying creatures in a new way: by firing tardigrades from a gun. Tardigrades survived smashing into targets at speeds up to about 825 meters per second, researchers report online May 11 in Astrobiology. But speedier water bears blew apart on impact. The findings hint that even intrepid little animals like tardigrades would struggle to survive crash-landing on a new planet. That puts new limits on the possibility of panspermia — organisms hitchhiking between worlds on planetary debris kicked up by meteorite impacts (SN: 8/26/20). Knowing whether life is up to the challenge of planet-hopping could help answer how life got started on Earth and gauge the risk of Earthly lifeforms on spacecraft contaminating other places in the solar system, says Samuel Halim, a planetary scientist at Birkbeck, University of London not involved in the work. The inspiration to test water bears’ ability to withstand high-speed impacts came from the tardigrade-toting Israeli spacecraft Beresheet, which crashed into the moon in 2019 (SN: 4/11/19). “I wondered, are these tardigrades alive?” says astrobiologist Alejandra Traspas Muiña of Queen Mary University of London. After freezing Hypsibius dujardini tardigrades to put them in a state of suspended animation, Traspas Muiña and planetary scientist Mark Burchell of the University of Kent in England loaded the dormant water bears into nylon bullets. The researchers fired those bullets from a five-meter-long instrument called a two-stage light gas gun, which looks more like a cannon than a firearm. The machine launched tardigrades at different speeds, ranging from about 550 to 1,000 meters per second, into bags of sand meant to mimic the lunar surface.
6-1-21 The teeth of ‘wandering meatloaf’ contain a rare mineral found only in rocks
The giant Pacific chiton’s use of santabarbaraite could inspire materials for soft robotics. The hard, magnetic teeth of a leathery red-brown mollusk nicknamed “the wandering meatloaf” possess a rare mineral previously seen only in rocks. The mineral may help the mollusk — the giant Pacific chiton (Cryptochiton stelleri) — meld its soft flesh to the hard teeth it uses for grazing on rocky coastlines, researchers report online May 31 in Proceedings of the National Academy of Sciences. C. stelleri is the world’s largest chiton, reaching up to roughly 35 centimeters long. It is equipped with several dozen rows of teeth on a slender, flexible, tonguelike appendage called a radula that it uses to scrape algae off rocks. Those teeth are covered in magnetite, the hardest, stiffest known biomineral to date: It’s as much as three times as hard as human enamel and mollusk shells. Materials scientist Derk Joester and colleagues analyzed these teeth using high-energy X-rays from the Advanced Photon Source at Argonne National Laboratory in Lemont, Ill. They discovered that the interface between the teeth and flesh contained nanoparticles of santabarbaraite, an iron-loaded mineral never seen before in a living organism’s body. These nanoparticles help the underpinnings of the teeth vary in hardness and stiffness by at least a factor of two over distances of just several hundred micrometers — a few times the average width of a human hair. Such variations let these structures bridge the hard and soft parts of the mollusk’s body. Now that santabarbaraite has been found in one organism, the researchers suggest looking for it in insect cuticles and bacteria that sense magnetic fields. Using nanoparticles of a mineral similar to santabarbaraite, the scientists also 3-D printed strong, light materials with a range of hardness and stiffness. These composites might find use in soft robotics, including marrying soft and hard parts in bots that can squirm past obstacles that conventional robots cannot given their rigid parts, says Joester, of Northwestern University in Evanston, Ill.