9-30-21 Female cleaner fish can judge when to cheat without getting caught
Female cleaner fish are sensitive to what their partners can and cannot see while working on client fish. This means they may have theory of mind, a concept built on awareness of other’s perspectives, often associated with humans and other primates. Cleaner wrasse (Labroides dimidiatus) typically work in male-female pairs to “clean” client fish by eating their dead skin cells and skin parasites. The wrasse actually prefer to eat the mucus produced by these client fish, but the clients can react to this by terminating the relationship – leaving the cleaners without food. This means a lot is at stake when a male-female cleaner wrasse pair work as a team. If one fish cheats by attempting to eat mucus while their partner is cooperating with the client, this may leave both fish without food. If a male cleaner fish knows his female partner has cheated, he will sometimes punish her by chasing and even attempting to bite her, says Katherine McAuliffe at Boston College in Massachusetts. But this made McAuliffe and her colleagues wonder whether females had developed ways to cheat without the knowledge of the males. “Because punishment is on the line and females would benefit from getting away with cheating, we had reason to suspect that they might show this sensitivity to what their male partner can and cannot see,” she says. In an experimental set-up, females had the choice of feeding in a tank with transparent or opaque barriers while their male partner was in a separate part of the tank with either a transparent or opaque partition. The researchers demonstrated that female cleaner fish are indeed more likely to cheat when their male partners are out of view. The team also found that females paired with more punitive males cheated more strategically by moving behind the opaque barriers. This sensitivity suggests that cleaner wrasse have evolved cognitive abilities that allow them to find solutions to their problems on a par with other animals, such as corvids and primates.
9-30-21 Some female butterflies can see an extra ultraviolet colour
Female red postman butterflies see an extra colour in the ultraviolet part of the light spectrum that even the males of their species cannot. While many animal species can see one colour of UV, the ability to see multiple colours in the UV spectrum is rare. Mantis shrimp and hummingbird hawkmoths may also see multiple colours of UV, according to Susan Finkbeiner at California State University, Long Beach, and Adriana Briscoe at the University of California, Irvine. Finkbeiner trained 80 Heliconius erato, an American butterfly species, and 120 of two other butterfly species to sip from a feeder placed on a light source that was tuned to a specific UV wavelength. She says that while training butterflies is difficult, the relatively big brains of Heliconius butterflies make them “the Einsteins of the butterfly world”. After training, the butterflies were allowed to fly within an enclosure where two UV light sources were each tuned to a different UV colour. The H. erato males and all the butterflies of the other two species flew towards whichever light was the brightest. When the two lights were equally bright, they landed on the light that had a watered-down honey reward on it about half the time, showing that they couldn’t tell the difference between the two UV colours, the researchers concluded. The H. erato females correctly chose the UV colour associated with the honey reward under every testing condition, even if the other UV light was 15 times brighter. “Each sex in this butterfly species literally sees the world through different eyes,” says Briscoe. This suggests a division of labour by sex, perhaps similar to that seen in squirrel monkeys, where only females can differentiate between red and green, making them specialists in finding ripe fruits for their group.
9-30-21 US declares 23 bird, fish and other species extinct
The ivory-billed woodpecker is among 23 species declared extinct by the US Fish and Wildlife Service (FWS). The service has proposed removing them from the Endangered Species Act (ESA), which protects species under threat. In all, 11 birds, one bat, two fish, one plant and eight types of mussel have been declared extinct. The FWS said it had made the determination based on "rigorous reviews of the best available science for each of these species". "Each of these 23 species represents a permanent loss to our nation's natural heritage and to global biodiversity," Bridget Fahey, who oversees species classification for the Fish and Wildlife Service, was quoted as saying in the New York Times. "And it's a sobering reminder that extinction is a consequence of human-caused environmental change." The ivory-billed woodpecker was once the US's largest woodpecker species but the last commonly agreed sighting was in 1944 in Louisiana. The species was officially listed as endangered in 1967. Another bird declared extinct is the Bachman's warbler, which was one of the rarest songbirds in North America. It too has been listed as endangered since 1967. Eight species of birds from Hawaii and the Little Mariana fruit bat from the Pacific island of Guam are also on the list. The FWS, in its statement, said the protections afforded by the ESA, which came into effect in 1973, had come too late for these species. But it stressed the act has been successful at preventing the extinction of more than 99% of species listed, and its protections are needed now more than ever. "The Service is actively engaged with diverse partners across the country to prevent further extinctions, recover listed species and prevent the need for federal protections in the first place," said Martha Williams, FWS Principal Deputy Director. "The Endangered Species Act has been incredibly successful at both preventing extinctions and at inspiring the diverse partnerships needed to meet our growing 21st century conservation challenges."
9-29-21 Brexit paves the way for gene-edited crops
The UK government is to relax the regulation of gene-edited crops to enable commercial growing in England. The plants are to be tested and assessed in the same way as conventional new varieties. The changes are possible because the UK no longer has to follow European Union regulations, which are the strictest in the world. The Scottish, Welsh and Northern Irish governments will get to decide whether to adopt or opt out of the changes. Environment Secretary George Eustice said that he would be working closely with farming and environmental groups to help grow plants that are stronger and more resilient to climate change. "Gene editing has the ability to harness the genetic resources that nature has provided. It is a tool that could help us tackle some of the biggest challenges that we face." Gene-edited (GE) crops have much simpler genetic alternations than so-called genetically modified (GM) ones. GM crops often involve the addition of extra genes, sometimes from a completely different species; and in some instances the insertion of DNA from animals. Gene-edited crops, by contrast, often just have genes snipped out of them, producing new varieties within months that could also have been produced by traditional cross-breeding but over a period of several years. Scientists believe that they can use gene editing to develop fruit, vegetables and cereals that are more nutritious and productive, as well as hardier varieties that can withstand the extremes of weather brought about by climate change. European Union regulations require that gene-edited crops are treated the same as genetically-modified crops. These rules call for a number of field trials over a period of several years, as well as extensive food safety tests. The final hurdle is for member states to vote to approve a new variety. This approach is regarded by biotech companies as too onerous and expensive, so no genetically altered crops are developed in the European Union. The Westminster government's plan begins with separating the laws governing GE and GM crops. As a first step, legislation will be passed later this year to do away with the need for scientists to apply for a licence to carry out open-air trials of a gene-edited crop that could have been produced through traditional cross-breeding. Currently, the approvals process can take up to two months and cost several thousand pounds.
9-28-21 It’s now easier to run trials testing CRISPR-edited crops in England
Law changes later this year will make it easier to run field trials in England on crops that are gene-edited for environmental and nutritional benefits. The UK government, which announced the move today, also said it plans future legislation so gene-edited crops and livestock that mimic the effects of natural breeding are treated differently to genetically modified (GM) ones, a step that would pave the way to gene-edited food being sold in UK supermarkets for the first time. Gene editing sees the DNA of an organism precision-targeted, often using CRISPR technology. This means gene editing doesn’t involve inserting whole genes or genes from other species, which other GM crops may carry. A recent example tested in the real-world involved wheat edited to lower the risk of a carcinogenic compound forming when bread made from the wheat is toasted. Proponents say such edited crops simply speed up natural breeding techniques, and could bring environmental benefits such as reducing pesticide use by developing blight-resistant potatoes. The UK approach signals a post-Brexit divergence from the European Union, which regulates gene-edited organisms in the same way as GM ones, effectively banning them from being grown and sold. The UK carried over that regulation when it left the EU. Today’s first step away from that regulation is a modest one following a consultation. The government will lift the licensing hurdles that laboratories face when starting a field trial of gene-edited crops, a crucial exercise to see how well they grow in more realistic conditions. The change in England, to be undertaken using secondary legislation before the year is out, should save about £10,000 per trial and cut a two month wait before trials can begin. Wendy Harwood at the John Innes Centre in Norwich, UK, says: “We’re hoping it will make it easier to have a look at these plants in the field, which will enable scientists to identify which ones to take forward.”
9-28-21 57 per cent of elephants at Thai tourist facilities have nervous tics
More than half the elephants in multiple Thai tourist facilities have nervous tics that may reflect anxiety, frustration or boredom. The involvement of scientists in the elephant tourism industry has led to improvements in welfare, but many captive Thai elephants still develop repetitive behaviours called stereotypies, which are similar to nervous tics. Pakkanut Bansiddhi at Chiang Mai University in Thailand and her colleagues observed the behaviour of 283 Indian elephants (Elephas maximus indicus) in 20 tourist facilities in Thailand’s Chiang Mai province where elephants give tourists rides, walk side by side with them and participate in shows. The team found that 57 per cent of these elephants showed repetitive behaviours, including swaying side to side, weaving or pacing around, bobbing their heads, making useless limb movements and rocking back and forth on their feet, at least once in a 15-minute period. This might be their way of dealing with stressful situations like separation from family members or being restrained in chains, or even coping with boredom, says Bansiddhi. On average, the elephants did these things about six times in that period. The highest prevalence was in elephants aged between 4 and 10. Those younger than 3 and older than 50 were least likely to show these behaviours. Bansiddhi says this is more or less consistent with the statistics her team calculated from direct interviews with 181 mahouts, or elephant handlers, on the animals’ behaviour. “I’m surprised the figures are not higher than that,” says Andrew McLean at the Human Elephant Learning Programs foundation in Australia. “Wherever they chain elephants, there are almost always locomotor stereotypies.” Mahouts generally separate young elephants from their mothers when they are 3 or 4 years old. Before that, the youngsters may experience relatively little stress, says Bansiddhi. But after the separation, their tics could reflect how anxious they are in their new situation. Older elephants may have simply “learned to cope better with the stress in their environment”, she says. McLean, however, wonders if older elephants have reached a state called learned helplessness, in which animals give up trying to cope.
9-28-21 California high schoolers rescue 4,000 endangered salmon
The students at Casa Grande High School in Petaluma, California, have stepped up to save endangered coho salmon. In 1993, the school built a large hatchery on campus, where students typically raise steelhead trout. Because of California's drought, the water became too warm for 4,000 endangered coho salmon at a Lake Sonoma hatchery, and they were moved to Casa Grande, where the tanks can be kept at an optimal temperature for the fish. Manfred Kittel of the California Department of Fish and Wildlife told The San Francisco Chronicle he was impressed by the quality of the program and "professionalism" of science teacher Dan Hubacker, who oversees the hatchery, and his students. Before students are allowed to participate in the program, they must take a conservation and biology class and pass two safety tests. It's a full-time job taking care of the fish, with students coming in on the weekends to feed them. This is the first time Casa Grande has had the chance to rescue an endangered species, and the students are up for the challenge. "We have this opportunity to save coho salmon, to see that we can do it, if people put their minds to it," Kate Carlson, 17, told the Chronicle.
9-24-21 Tomato is first CRISPR-edited food to go on sale in the world
For the first time ever, you can now buy a food altered by CRISPR gene editing – at least, if you live in Japan, where the Sicilian Rouge High GABA tomato has just gone on sale. “We started shipping the tomatoes on September 17,” says Minako Sumiyoshi at Japanese start-up Sanatech Seed, which is selling the tomatoes directly to consumers. She says demand for the tomatoes is “not too bad”. “It is a very significant milestone for CRISPR foods,” says Nigel Halford at Rothamsted Research in the UK. Earlier this year, Sanatech Seed also gave away seedlings to anyone who wanted to grow the gene-edited tomatoes themselves. Around 4200 gardeners took up the offer, says Sumiyoshi. As far as New Scientist has been able to establish, the tomato is the first food altered with CRISPR to be launched commercially anywhere in the world. Consumers in the US are already eating gene-edited soybean oil, but it was created using an older method of gene editing. “Looking at the media, it seems like our tomato is the first CRISPR/Cas9 product, but we don’t know if it really is,” says Sumiyoshi. “As far as I know [it is the first],” says Jon Entine at the Genetic Literacy Project, a US-based non-profit organisation. “Corteva’s CRISPR corn has gotten clearance in Canada, but I’ve not heard that it’s yet released.” A non-bruising mushroom created by CRISPR was approved in the US in 2016, says Halford. “However, I do not know if it went on sale.” The Sicilian Rouge High GABA tomato produces less of an enzyme that breaks down the amino acid GABA, or gamma-aminobutyric acid, resulting in the tomatoes containing five times as much GABA as normal tomatoes. GABA is produced in our bodies and plays a key role in the brain and nervous system. It is also sold as a dietary supplement. The benefits of eating extra GABA are debated, but a review of the evidence last year concluded that “GABA intake may have beneficial effects on stress and sleep”.
9-24-21 Bloodthirsty vampire bats like to drink with friends over strangers
Social bonds extend beyond the roost and may save time and energy when hunting. Vampire bats may be bloodthirsty, but that doesn’t mean they can’t share a drink with friends. Fights can erupt among bats over gushing wounds bit into unsuspecting animals. But bats that have bonded while roosting often team up to drink blood away from home, researchers report September 23 in PLOS Biology. Vampire bats (Desmodus rotundus) can form long-term social bonds with each other through grooming, sharing regurgitated blood meals and generally hanging out together at the roost (SN: 10/31/19). But whether these friendships, which occur between both kin and nonkin, extend to the bats’ nightly hunting had been unclear. “They’re flying around out there, but we didn’t know if they were still interacting with each other,” says Gerald Carter, an evolutionary biologist at Ohio State University in Columbus. To find out, Carter and his colleague Simon Ripperger of the Museum für Naturkunde in Berlin, built on previous research that uncovered a colony’s social network using bat backpacks. Tiny computer sensors glued to 50 female bats in Tolé, Panama, continuously registered proximity to other sensors both within the roost and outside, revealing when bats met up while foraging. Bat buds rarely left the roost together, suggesting that they don’t go on tightly coordinated hunts, Carter says. But bats with a history of associating with one another were more likely than strangers to meet up in the field and likely feed together, the researchers found. Rendezvous with friends also lasted longer, on average, than other interactions. That was especially true for bats with many roost buddies. “These are more or less haphazard encounters,” Carter says. He suspects that the bats mostly forage alone, but when they encounter a friendly bat on a cow, for instance, they’ll feed together instead of fighting or flying off to find other food. Biting a new wound can take 10 to 40 minutes, Carter says, so sharing with a friend could save these bloodthirsty bats time and energy.
9-23-21 Hyenas make faces at each other when they want to play-fight
Hyenas engage in plenty of play-fighting, and they have a way to let fellow hyenas know when an attack is part of a game: they bob their heads and make clear facial expressions. Known for their particularly vicious fights and a strong dominance order in their clans, hyenas also frequently spend long periods of time play-fighting with each other. But they always make sure the message is clear that they don’t intend to be aggressive, especially if the fight is uneven, says Elisabetta Palagi at the University of Pisa, Italy. “It seems that if I want to play hard, I need signals to clarify that I am not attacking you, and that this is only play,” says Palagi. Palagi and her colleagues used multiple video cameras, including some motion-activated ones, to gather 38 hours of play-fighting footage among 24 wild spotted hyenas (Crocuta crocuta) at the Greater Makalali Private Game Reserve in Limpopo, South Africa. Their analyses revealed that adults will regularly play-fight with other adults or with juveniles – while juveniles will also play-fight with each other – and that they consistently use subtle body language to communicate with each other that the fight isn’t serious, says Palagi. That body language involves mostly a relaxed, open mouth – similar to that previously reported in dogs, bears, seals and chimpanzees when they play-fight – but also a characteristic head bobbing, somewhat reminiscent of a bobblehead toy. Hyenas bob their heads during other gentle interactions with each other as well, such as before mating or affiliative behaviours like muzzle rubbing. But the relaxed, open mouth is used specifically during playtime, says Palagi. Surprisingly, the more unbalanced the play-fight is – meaning when one hyena was clearly “winning” and the other “losing” – the longer the play session lasts, says Palagi. In most animals, when the play-fight gets too uneven, the players either stop the fight or it escalates into true fighting. But hyenas seem to have an alternative approach. “This is completely different from any other species,” she says. “It’s incredible.”
9-22-21 Does talking or singing to plants help them to grow better?
Some people believe that talking or singing to plants helps them to grow better and produce more fruit. Is there any truth in this? This is a question that I am often asked because I do research on how plants respond to the vibrations that occur naturally in their environment. Sound is perceived as vibrations. There is no consistent scientific evidence that talking or singing to plants helps them grow better or produce more fruit. Some studies have shown an effect on plants from music or single tones, some haven’t. These studies are rarely done in the same way, making them difficult to compare, so there is no consensus yet. We know that plants can sense some vibrations that are important to them. Some plants like tomatoes are “buzz pollinated” and only release pollen when the anthers in their flowers experience the wing beat frequency of a pollinator. There is one example of a plant producing more nectar in response to pollinator vibrations. “Sometimes I eat plants alive. It would be very troubling if they had an emotional response to this treatment” My work with Rex Cocroft at the University of Missouri has shown that plants can detect the vibrations caused by caterpillars feeding and they increase their chemical defences in response. There is exciting research ahead in figuring out what plants do and don’t sense and respond to in their natural environment. So, should you play music to, or sing to, your plants? Well, it probably won’t hurt them and if it makes you want to take better care of them, why not? When people talk or sing to their plants, they probably spend more time and pay more attention to the plant than they would otherwise. This helps them to notice when something is wrong, like if they need water, or weeding. I am sure this is why plants appear to do better when people talk or sing to them. Some people believe that plants respond emotionally to singing or talking. I hope they are wrong, because I routinely rip my plants out of the ground, chop them up, then boil them to death. I eat some of them alive. It would be very troubling if they had an emotional response to this treatment.
9-22-21 Birds flocked to North American cities during covid-19 lockdowns
As human movements were restricted to limit the spread of covid-19 in early 2020, dozens of bird species became more abundant in urban centres in the US and Canada. Nicola Koper at the University of Manitoba in Winnipeg, Canada, and her colleagues analysed 4.3 million observations made by volunteer birdwatchers to compare numbers during the pandemic restrictions with those in previous years. Between March and May 2020, 66 of 82 species of birds observed by the birdwatchers across 93 North American counties displayed different land use patterns compared with those in the same months in pre-pandemic years. Most birds were seen spending more time in urban areas and near major roads and airports. The researchers adjusted the results to control for time spent birdwatching and the distance people had travelled to rule out the possibility that volunteers simply had more time to observe birds in urban regions at that time. Birds probably flocked to such areas during the restrictions because there was less noise and air pollution from traffic, which dropped by 8 to 25 per cent across the included counties, says Koper. “The fact that birds consistently moved into these areas when we reduced traffic tells us how much of an impact human traffic has on them.” Attracting more birds to urban spaces could help boost their numbers, which have declined by 3 billion in North America since 1970, largely due to habitat loss, says Koper. In return, birds provide us with pest control, help pollinate our crops and gardens and improve our psychological well-being, she says. “Research shows if you’re surrounded by more species of birds, you have better mental and emotional health.” To keep birds in urban areas, we should find ways to continue limiting car and air traffic, says Koper. For example, we could invest in public transport and quieter, zero-emissions electric cars, promote working from home and hold more virtual events so that people don’t need to travel, she says.
9-22-21 Study reveals kids on field trip discovered a new species of giant penguin
During a fossil-hunting excursion in January 2006, members of the Hamilton Junior Naturalist Club came across a major discovery in Waikato, New Zealand, although it took years to fully understand just what they uncovered. While in the upper Kawhia harbor, the children and their archaeologist guide noticed several fossils that looked different from the crustaceans they normally spotted. In a new study recently published in the Journal of Vertebrate Paleontology, scientists from Massey University announced that the kids found a new species of prehistoric penguin, having stumbled upon the most complete fossilized skeleton of an ancient giant penguin yet discovered. The fossil was donated to the Waikato Museum, and a team of researchers ultimately named the new species waewaeroa, Maori for "long legs." The penguin is between 27.3 and 34.6 million years old and when standing up was likely around five feet tall. Not much is known about the prehistoric giant penguins of New Zealand, and former club member Steffan Safey, who was 13 when the fossil was found, told The Guardian it's "sort of surreal to know that a discovery we made as kids so many years ago is contributing to academia today, and it's a new species even."
9-20-21 Endangered South African penguins killed by swarm of bees near Cape Town
Sixty-three endangered African penguins have been killed by a swarm of bees in a rare occurrence near Cape Town, bird conservationists in South Africa say. The protected birds, from a colony in Simonstown, were found on the shore with multiple bee-stings. They had no other physical injuries. National parks officials told the BBC this was the first known attack at the world-famous Boulders Beach, which attracts up to 60,000 visitors a year. "Usually the penguins and bees co-exist," said Dr Alison Kock, a marine biologist with South Africa's national parks agency (SANParks). "The bees don't sting unless provoked - we are working on the assumption that a nest or hive in the area was disturbed and caused a mass of bees to flee the nest, swarm and became aggressive," she added. "Unfortunately the bees encountered a group of penguins on their flight path." Post-mortems found that the birds had been stung around the eyes and on their flippers. That is because "those are the parts that are not covered by feathers," Dr Katta Ludynia, from the Southern African Foundation for the Conservation of Coastal Birds (Sanccob), told the BBC. One of the penguins had been stung 27 times. "Seeing the number of stings in individual birds, it would have probably been deadly for any animal of that size," Dr Ludynia added. Honeybees die after stinging and a number of dead bees were found at the scene. "Once a honeybee has stung something, it leaves a pheromone behind so that the target is easily located by other honeybees defending the nest," said Jenny Cullinan of the African Wild Bee Institute, which is asking residents to stop keeping beehives in their gardens. African penguins are distinctive for their small size, and live on the coast and islands of South Africa and Namibia - though some have been spotted as far north as Gabon. Their populations are rapidly declining, the International Union for Conservation of Nature says, in main part because of commercial fishing and what it calls "environmental fluctuation".
9-17-21 Watch cuttlefish migrate together in a defensive line with a lookout
The cuttlefish has a reputation for being a rather solitary cephalopod. But new footage reveals that groups of wild cuttles form shoals to migrate, suggesting they are more social than we thought. Grouping is common across the animal kingdom, giving a range of benefits including help foraging, fending off predators and meeting to mate. In cephalopods, the behaviour is mostly associated with squids, which form schools of thousands. Cuttlefish, like octopuses, mostly prefer to explore the world on their own, and sightings of social behaviour are rare. Christian Drerup at the University of Cambridge in the UK and Gavan Cooke at The Cephalopod Citizen Science Project have collected a series of reports, photos and videos of sent in by local scuba divers from waters off the south coast of the UK that show 10 examples of shoaling in the European cuttlefish (Sepia officinalis). “The literature is very dogmatic about what cephalopods do and don’t do, and you kind of accept that until you see things with your own eyes,” says Cooke. In the videos, cuttlefish can be seen traveling together in a series of formations, some in groups as large as 30. Sometimes they formed a horizontal line, with one cuttle facing the other direction – possibly acting as a guard while the others slept. At other times, the cuttlefish made a spherical shape, facing outwards in all directions like the Roman army testudo formation. Sometimes the cuttlefish would drift apart before returning to a group structure. The observations were made between 2013 and 2020 during August to September, when these cuttlefish start migrating from their nursery grounds in shallow coastal waters toward deeper waters in the English Channel and northern coast of France. “Shoaling allows for selfish herd defence,” says Cooke, providing safety in numbers against a range of predators along the journey. It also likely improves navigation, and may also offer an opportunity for social learning.
9-16-21 Mystery microbes have been lurking unsuspected in most coral species
It has long been known that coral polyps harbour algal symbionts that make most of their food. Now it has been shown that corals can also harbour microbes that appear to be parasites but don’t seem to harm their hosts. “The fact that we could go out to a coral reef, which is probably the best studied marine environment, and specifically look at the coral, which is the best studied part of that environment, and find a parasite that infects virtually every species of coral we’ve looked at, that no one had ever really noticed, blows my mind,” says Patrick Keeling at the University of British Columbia in Canada. “How much out there that is still unknown is bewildering sometimes.” The organelle that carries out photosynthesis inside plant cells has its own tiny genome. A group of single-celled parasites – including malaria – that evolved from algae still have relics of this organelle and its genome. Similar sequences had turned up in so-called metagenomic studies of corals but were thought to be contaminants or belong to bacteria. Around a decade or so ago, Keeling and his colleagues realised that these sequences actually belonged to a previous unknown group of single-celled organisms with complex cells, unlike bacteria. The team has gone on to find and isolate these organisms, dubbed corallicolids. They don’t obviously harm corals but are almost certainly parasites, says Keeling. “It’s really hard to see how they could be beneficial,” he says. What is most mystifying is that that corallicolids appear to make a little chlorophyll that can capture light energy but have lost the apparatus for using that energy to make food. This captured energy can damage cells if there is no way to exploit it – it is like having a bomb inside a cell with no way to defuse it, says Keeling. “It’s hard to describe how mind-boggling it is,” he says. “Biochemists just flat out refuse to believe it.”
9-16-21 Some birds learn to recognize calls while still in their eggs
Prenatal sound perception is more widespread than previously thought, new research suggests. Over a decade ago, behavioral ecologist Diane Colombelli-Négrel was wiring superb fairy wrens’ nests to record the birds’ sounds when she noticed something odd. Mother fairy wrens sang while incubating their eggs, even though it would have made more sense to keep quiet to avoid attracting predators. The discovery “was a bit of an accident,” says Colombelli-Négrel, of Flinders University in Adelaide, Australia. And it made her wonder: Could the baby birds be learning sounds, or perhaps even songs, even before they hatch? Scientists have long wondered how early in development individuals learn to perceive distinct sounds. It’s known that human fetuses learn to recognize their mother’s voice (SN: 1/7/13). For birds such as superb fairy wrens (Malurus cyaneus) that perfect their songs with parental tutoring, it was thought that sound perception began well after hatching. But when it became obvious that mother birds were intentionally singing to their eggs, “we knew we were on to something,” says avian ecologist Sonia Kleindorfer of the University of Vienna. Previous research by Colombelli-Négrel, Kleindorfer and colleagues showed that unhatched superb fairy wrens learn a vocal “password” from mom that helps mothers discriminate their own nestlings from those of pesky cuckoo invaders (SN: 5/9/14). What’s more, unhatched superb fairy wrens appear to distinguish between songs of their own species and others, the team reported in 2014. That ability extends beyond superb fairy wrens, new research suggests. At least four additional types of birds recognize sounds specific to their species while still in their eggs, the researchers report in the Oct. 25 Philosophical Transactions of the Royal Society B.
9-16-21 Cats refuse to snuggle with objects that smell like their owners
Anxious cats aren’t comforted by objects that smell like their favourite person – and these reminders could even make them howl more in their owner’s absence. Most pet cats form strong bonds with their caretakers and appear to find their presence reassuring. However, unlike human babies, cats don’t accept scent alone as a worthy stand-in for the people they have bonded with, says Kristyn Vitale at Unity College in Maine. “Olfaction is an important sense for cats, and it’s related to their social behaviour, but in our study, [owner-scented objects] did not have a stress-reducing effect,” she says. “The smell might even make matters worse for some cats.” Cat owners are sometimes told to leave an item of their clothing with their pets when they have to be separated from them, such as in a pet hotel. To see whether this practice is actually helpful, Vitale and her colleagues asked 42 cat owners to bring their cats and something that smelled like themselves – a shoe, a sock, a nightshirt or a blanket – to an unfamiliar testing room. Each owner sat in the middle of a 2-metre-wide circle on the floor, while their cat was allowed to roam freely throughout the room. Then the owner left the cat alone. Afterwards, the cats experienced one of two sequences. For some, their owner came back, then left them alone again, and then finally a scented object was left in the room with the cat; for others, the object was presented first and then the owners returned after the cat had been alone for a period. The majority of the cats showed signs of bonding with their owners, rubbing against them when they returned to the room and meowing nervously when they were absent, says Vitale. Regardless of which sequence they experienced, the cats generally paid no attention to the scented object and didn’t act any calmer than when they were alone without the object.
9-16-21 Australian bandicoot brought back from brink of extinction
A small furry marsupial that roamed plains in Australia has been brought back from the brink of extinction on the country's mainland, officials say. Numbers of the Eastern Barred Bandicoot plummeted on the mainland because of foxes and habitat destruction. Now, after 30 years of conservation efforts, the number has jumped from just 150 animals to an estimated 1,500. It is the first time Australia has changed the status of an animal from "extinct in the wild" to "endangered". When recorded population levels of the bandicoots plunged in Australia's Victoria state in the years leading up to the late 1980s, conservation teams invested millions of dollars setting up captive breeding programmes. They created predator-free sites - some of which were protected by trained dogs - and moved some of the animals to fox-free islands. Announcing the change in conservation status of the bandicoot on Wednesday, Victoria's Environment Minister Lily D'Ambrosio said she was "excited" about the project's success, adding: "It is an incredible first for Australia." A threatened species biologist at Zoos Victoria in Melbourne, Amy Coetsee, said the news offered "hope that with persistence, determination and the support of government, volunteers and communities, we can win the fight against extinction", AFP news agency reported. Australia has the worst mammal extinction rate of any country in the world, according to World Wildlife Fund (WWF) Australia.
9-16-21 Mangrove forests: Photography winners show beauty of ecosystems
Musfiqur Rahman has been named overall winner of this year's Mangrove Photography Awards, for his image of a wild honey gatherer subduing giant honeybees with smoke, in Bangladesh. Run by the Mangrove Action Project, the competition - now in its seventh year - aims to show the relationships between wildlife, coastal communities and mangrove forests, as well as the fragility of these unique ecosystems, both above and below the waterline. Rahman's winning image, A Brave Livelihood, was selected from more than 1,300 entries from 65 countries. "Indigenous Mowal honey gatherers, protected by Bonbibi, the forest goddess, must evade the dangers (Bengal tigers and saltwater crocodiles) lurking in the mangroves," says Rahman. "This ancient tradition and sustainable relationship between people and the mangrove forest takes place in the Sundarbans in Bangladesh, and also India." Mangroves are an important protection against climate change, with one acre (4,000 sq m) of mangrove forest absorbing nearly the same amount of carbon dioxide as an acre of Amazon rainforest. The forests also protect coastlines from eroding as intense storms grow more frequent. "Today, less than half the world's original mangrove forest cover remains," says competition judge Robert Irwin. "It has never been more important to promote the conservation of these fragile ecosystems through inspiring photography." Here is a selection of winning images from six competition categories, with descriptions by the photographers.
9-16-21 Kew Gardens: Royal Botanic Gardens breaks record for largest plant collection
Kew Gardens has set a new record for the largest living plant collection at a single site, according to Guinness World Records (GWR). Established in 1759, the Royal Botanic Gardens (RBG) at Kew had 16,900 unique plant species as of May 2019. This makes it the most diverse collection of living flora at a single-site botanic garden, GWR said. Richard Barley, director of horticulture at RBG, called the award "a fantastic accolade". Mr Barley said: "We are absolutely thrilled to hold the record for the largest living plant collection. "It re-enforces the importance of botanic gardens around the world, as not only beautiful places to enjoy, but as essential hubs of inspiration and education." Kew Gardens expects the record number of plants to rise significantly when it completes an ongoing stock-take of all its collections. The UNESCO World Heritage site contains many record-breaking plants including the Titan Arum, officially the worlds tallest and smelliest plant. In 2020, a specimen at the nursery at Kew earned the award for the Longest Nepenthes plant trap measuring 16.9 in (43cm) from the base to the lid. Also managed by RBG Kew is the world's largest seed repository, the Millennium Seed Bank - based at Kew's satellite Wakehurst facility in West Sussex. The bank contains more than 2.4 billion seeds from almost 40,000 species. Adam Millward, a managing editor of GWR, said: "I've had the dubious honour of smelling the pungent Titan Arum up close, contended with the steam and sprinklers to measure a prodigious pitcher trap for a GWR certificate. "It's fantastic to be able to celebrate the entire collection - surely one of the jewels of the botanical world - in the GWR 2022 book."
9-15-21 Why do dogs enjoy rolling in smelly fox or bird faeces?
A dog’s primary sense organ is its nose, and its primary sense is that of smell. Dogs identify each other, and probably us, too, by scent. This identification extends not only to the dog or person, but to the droppings they find. It has been said that “a lamppost is a dog’s social calendar”. It seems that the more powerful the predator, the stronger the smell of its droppings. I am told that tiger droppings are very pungent indeed. Those of a fox are notoriously rank. It seems fair to say that animals with pungent droppings are able to defend themselves, or at least are good at evasion. From this it appears that rolling in another animal’s droppings is a form of disguise as a creature that is more powerful. Young dogs seem to present themselves with a clear sense of pride in these circumstances, similar to when children dress up as superheroes. Rolling in smelly stuff is an evolutionary adaptation that goes back to canine pre-domestication times. Canids predisposed to this activity gave their descendants a paw up on the natural selection ladder. As the smelly stuff disguised dogs’ natural scent, it was thought that this would allow them to be better predators. However, researchers at the University of California discovered that grey foxes rubbed their faces in scent-marking areas used by pumas, a much larger predator. Smelling like a big feline predator wouldn’t help a fox much when approaching their prey. The researchers took the view that the foxes used the puma odour as a form of olfactory deception, in effect as a disguise that would act to deter other large predators which kill foxes, such as coyotes. Why do modern, domesticated dogs still love to writhe in smelly stuff? This hangover from their canid ancestors is fun. The activity stimulates the reward systems of the canine brain, releasing neurotransmitters that elicit pleasure, as is seen from a dog’s obvious delight after taking a roll in something mucky, much to the chagrin of its owner.
9-15-21 Global demand for fish expected to almost double by 2050
The world’s hunger for fish is expected to almost double by 2050 due to growing affluence and populations, according to an assessment that anticipates the demand being fed by a big rise in farmed seafood. Global fish consumption has already doubled since 1998, but a team led by Rosamond Naylor at Stanford University in California projects a further 80 per cent increase by mid-century. Whether that proves good or bad for the environment and nutrition will rest on what types of fish people choose to eat, the researchers say. “We talk about fish as a monolithic thing, but actually it’s highly diverse,” says Naylor’s colleague, Beatrice Crona at the Stockholm Resilience Centre in Sweden. “Preferences will play a big role to whether we can convince some people to eat small pelagic fish [such as sardines] or mussels, which are also low [environmental] impact but highly nutritious.” Supplying the increase in demand with a big expansion of farmed salmon, as pioneered by Norway and Chile, wouldn’t be feasible because of the environmental side effects and inefficiencies of a species so high up the food chain, says Crona. Salmon farming has been linked with water pollution, overfishing to feed them and spreading parasites to wild fish. Brazil, Ghana, India, Mexico and Nigeria are all expected to more than double the weight of fish they consume by 2050. China, meanwhile, will remain the biggest consumer, expanding its appetite from just over 50 million tonnes of fish in 2015 to just under 100 million by 2050. The growth is expected to decrease meat and dairy demand per person in countries, including China and the US, and raise the intake of iron, calcium and vitamin B-12. The researchers arrived at their figures using modelling based on UN Food and Agriculture Organization (FAO) data on what fish species people ate in 10 countries that account for 55 per cent of global fish consumption, and on World Bank and International Monetary Fund estimates of future economic and population growth. The researchers considered the 10 countries indicative of global trends. The projections don’t simply assume a linear increase from 2015, but factor in shifts in the species people eat as they get richer.
9-15-21 Why are orcas ‘attacking’ fishing boats off the coast of Gibraltar?
MARTIN EVANS, a sailor on his way to Greece, was about 80 kilometres from Gibraltar on 17 June when he saw the orcas. “I knew immediately that we were having a major issue,” he says. “I jumped onto the helm and tried to hand steer the boat, but it was ripped from my hands with tremendous force.” For 2 hours, about a dozen orcas, also known as killer whales, circled the boat, bashing repeatedly against the bottom. “At one point, I looked astern and saw bits of the rudder that were broken off floating away,” he says. An increasing number of orca interactions like these have been reported since marine traffic started returning to the Strait of Gibraltar in mid-2020, after the lifting of pandemic lockdown measures. There were 41 reported encounters in July 2021 and 25 in August, all along the Iberian Peninsula, but mostly in Gibraltar’s waters. On 5 August, just off Cape Trafalgar, sailors Elisabeth Heigl-Berger and Markus Berger were surrounded by orcas when they noticed parts of their rudder floating away. “They appeared out of nowhere,” says Heigl-Berger. “The whales turned our sailing yacht in a circle, pushed us back and forth and swam again and again under the ship to hit the rudder and the keel.” The encounter lasted more than an hour. Local fisher Joey Catania was one of the rescuers called to tow the boat to safety. Recalling the moment he pulled up next to them, he says, it was clear “they had feared for their lives”. Catania, who has fished in Gibraltarian waters for decades, says these interactions are very unusual for this critically endangered subpopulation of orcas (Orcinus orca). These orcas were already known to take Atlantic bluefin tuna (Thunnus thynnus) from the lines of fishing boats. “The killer whales would patiently wait for the fishermen to catch and fight with the fish until it was exhausted and then, once the fishermen were ready to bring it on board, they would ‘attack’, bite and steal the tuna,” says Susana García Tiscar at the Autonomous University of Madrid in Spain.
9-15-21 Potty-trained cattle could help reduce pollution
When nature calls, these cows use bathroom stalls. You can lead a cow to a water closet, but can you make it pee there? It turns out that yes, you can. Researchers in Germany successfully trained cows to use a small, fenced-in area with artificial turf flooring as a bathroom stall. This could allow farms to easily capture and treat cow urine, which often pollutes air, soil and water, researchers report online September 13 in Current Biology. Components of that urine, such as nitrogen and phosphorus, could also be used to make fertilizer (SN: 4/6/21). The average cow can pee tens of liters per day, and there are some 1 billion cattle worldwide. In barns, cow pee typically mixes with poop on the floor to create a slurry that emits the air pollutant ammonia (SN: 1/4/19). Out in pastures, cow pee can leach into nearby waterways and release the potent greenhouse gas nitrous oxide (SN: 6/9/14). “I’m always of the mind, how can we get animals to help us in their management?” says Lindsay Matthews, a self-described cow psychologist who studies animal behavior at the University of Auckland in New Zealand. Matthews and colleagues set out to potty train 16 calves, which had the free time to learn a new skill. “They’re not so involved with milking and other systems,” he says. “They’re basically just hanging out, eating a bit of food, socializing and resting.” Matthews was optimistic about the cows’ potty-training prospects. “I was convinced that we could do it,” he says. Cows “are much, much smarter than people give them credit for.” Each calf got 45 minutes of what the team calls “MooLoo training” per day. At first, the researchers enclosed the calves inside the makeshift bathroom stall and fed the animals a treat every time they peed. Once the calves made the connection between using the bathroom stall and receiving a treat, the team positioned the calves in a hallway leading to the stall. Whenever animals visited the little cows’ room, they got a treat; whenever calves peed in the hallway, the team spritzed them with water. “We had 11 of the 16 calves [potty trained] within about 10 days,” Matthews says. The remaining cows “are probably trainable too,” he adds. “It’s just that we didn’t have enough time.”
9-15-21 Faroe Islands: Anger over killing of 1,400 dolphins in one day
The practice of dolphin hunting in the Faroe Islands has come under scrutiny after more than 1,400 of the mammals were killed in what was believed to be a record catch. The pod of white-sided dolphins was driven into the largest fjord in the North Atlantic territory on Sunday. Boats herded them into shallow waters at Skalabotnur beach in Eysturoy, where they were killed with knives. The carcases were pulled ashore and distributed to locals for consumption. Footage of the hunt shows dolphins thrashing around in waters turned red with blood as hundreds of people watch on from the beach. Known as the grind (or Grindadrap in Faroese), the hunting of sea mammals - primarily whales - is a tradition that has been practised for hundreds of years on the remote Faroe Islands. The Faroese government says about 600 pilot whales are caught every year on average. White-sided dolphins are caught in lower numbers, such as 35 in 2020 and 10 in 2019. Supporters say whaling is a sustainable way of gathering food from nature and an important part of their cultural identity. Animal rights activists have long disagreed, deeming the slaughter cruel and unnecessary. Sunday's hunt was no different, as international conservation groups rounded on the hunters to condemn the killing. But the scale of the killing at Skalabotnur beach has shocked many locals and even drawn criticism from groups involved in the practice. Bjarni Mikkelsen, a marine biologist from the Faroe Islands, put the reported death toll into perspective. He said records showed that this was the largest number of dolphins ever killed on one day in the Faroe Islands, a autonomous territory of Denmark. He said the previous record was 1,200 in 1940. The next-largest catches were 900 in 1879, 856 in 1873, and 854 in 1938, Mr Mikkelsen said. In an interview with the BBC, the chairman of the Faroese Whalers Association, Olavur Sjurdarberg, acknowledged that killing was excessive.
9-14-21 Ancient spiders locked in amber died looking after their offspring
Modern spiders are known to take care of their eggs and young – and now we have evidence that the behaviour is ancient. Researchers at Capital Normal University in Beijing recently acquired four specimens of spiders trapped in Burmese amber, dated to 98.8 million years ago and mined in the Hukawng valley of northern Myanmar. In collaboration with Paul Selden at the Natural History Museum in London, the team analysed the pieces using photography and micro-computed tomography scanning. All four specimens feature lagonomegopids, an extinct spider family known especially for their large eyes – which are similar to those of modern Salticidae jumping spiders, says Selden. In one specimen, a 7.5-millimetre-long female lagonomegopid clutches an egg sac filled with embryonic spiderlings wrapped in silk. “I imagine this female guarding her egg sac would just remain completely silent and quiet while she was then engulfed in this resin,” says Selden. “That’s really very exciting in terms of showing fossilised behaviour.” The three other specimens contain 24, 26, and 34 recently hatched spiders – or spiderlings – respectively. In two of these specimens, the researchers also identified adult spider legs presumably belonging to the mother, and one of these two specimens also contained silk strands wrapped around pieces of wood and other debris – potentially remains of a spider nest. The findings hint that spiderlings in this species lived as a family in a nest guarded by the mother, says Selden. The preservation of the mother’s legs in two of the amber specimens suggest she would choose to stay with her offspring even as tree resin slowly immersed the nest. “It’s essentially being altruistic, I suppose, in biological terms, [when you’re] doing something that could be a danger to you in order to protect your offspring,” says Selden.
9-14-21 Jaguars face major threat from Amazon deforestation and fires
Fires and logging in the Brazilian Amazon pose a major threat to South America’s biggest cat, according to analysis of jaguars (Panthera onca) and their protected areas. Brazilian researchers found the apex predator’s last strongholds in the rainforest are also the sites with the most severe human pressures, including fires lit to clear land for cattle ranches. A team led by Juliano Bogoni at the University of Sao Paolo say their research pinpoints where limited conservation resources should be targeted to protect the species. The area occupied by the big cat, considered a “keystone species” emblematic of the wider health of an ecosystem, has halved. The team mapped jaguar densities in 447 protected areas of the Brazilian Amazon, where most of the remaining 57,000-plus animals rove. They then overlaid it with a ‘threat index’ they built using data on human pressures – fires, deforestation, road-building, mining, and cattle pastures – relative to the size of those protected areas. Cattle farms pose a “double-whammy”, the team say, because they not only remove jaguar habitat but ranchers then persecute and hunt the big cats. The results reveal the protected areas with the highest jaguar densities match those where human pressures are the greatest. These hotspots run roughly along the southern and eastern edges of the Amazon, known as the ‘arc of deforestation’. “This result seems counterintuitive,” says Bogoni. “But the leading drivers of habitat degradation – the deforestation and fires – are impending threats for large numbers of jaguars.” The Amazon saw extreme fires in 2019 in the wake of pro-logging and cattle-ranching rhetoric from Brazilian president Jair Bolsonaro. kilometres, as a priority for conservation funding and resources to best protect the big cats. However, he says their prospects “will likely become worse in the near future” unless the Brazilian government acts to strengthen protected areas with better enforcement and stronger penalties for those who start illegal fires.
9-14-21 Male rodents with less time to breed grow bigger testes
Male rodents with shorter breeding seasons tend to have larger testes, probably because the time pressure increases sperm competition between males. Studies have found that males typically have bigger testes when the females of their species have multiple mating partners. This is because their sperm must compete within the female reproductive tract to fertilise the eggs, meaning it is advantageous to have bigger testes that can produce more sperm. “It’s like a raffle – the more tickets you have, the more likely you are to win,” says Renee Firman at the University of Western Australia in Perth. Firman and her colleagues wondered if testes size may also be influenced by length of breeding season, since less time for mating should create more intense competition between males. They studied the relationship between the length of breeding season and testes size in 33 Australian rodent species that have females that mate with multiple males. Breeding season length was estimated using data from NASA’s Earth Observatory that showed when the habitats of each species produced enough food for them to reproduce. Testes size was measured by weighing museum specimens. As predicted, the results showed that species with shorter breeding seasons tend to have bigger testes. For example, the plains mouse (Pseudomys australis) has a relatively short breeding season because it lives in the desert region of central Australia where food is limited for much of the year. Males have large testes that are 3.5 per cent of their body weight. The western mouse (Pseudomys occidentalis), in contrast, can breed all year round because it lives in areas of high vegetation near the south coast of Western Australia. Males have smaller testes that are 0.5 per cent of their body weight.
9-14-21 Mary Roach’s new book ‘Fuzz’ explores the ‘criminal’ lives of animals
Roach profiles mugging monkeys, thieving bears and more. Around the world, criminals run free in the forest. These villains can’t be arrested — because they’re not human. In her latest book, Fuzz: When Nature Breaks the Law, Mary Roach puts the spotlight on these miscreants. On the Midway Islands, albatrosses carry out suicide missions against the U.S. Navy’s planes. In Colorado, bears break and enter, raiding the refrigerators of mountain homes. And deer do so much jaywalking. Nature’s perp list also includes camels, mountain lions, crows and many more. Through such examples, Roach tackles this question: What should we do when animals break laws intended for people? The book brims with Roach’s irreverent humor, which particularly shines when she experiences human-animal conflict firsthand. She tastes rat bait to better understand its allure and gets training on how to tell if a human body was mauled by a bear or by a human pretending to be a bear. She even engineers a robbery: “I had bananas. I was asking for it. I wanted to know what it was like to be mugged by monkeys.” But it’s not all fun and reindeer games. Roach highlights how much real pain comes from human-animal interactions. Elephants routinely destroy people’s crops and homes. They, along with leopards, bears, deer and others, can also kill people. She also tackles the ethics of eradicating pests by mass poisoning or altering their genetics. The stories might seem disparate, but they serve a wider point. Many wildlife strategies seek to save people from wild animals’ unwelcome behavior, or to increase the numbers of animals that people want to shoot, eat or admire. What would happen, Roach wonders, if we thought more about coexistence instead of conflict or exploitation?
9-13-21 Sea fireflies adapted their threatening glow to attract mates
Roughly half of all species of ostracods – bean-shaped crustaceans about the size of a sesame seed – can eject clouds of dazzling blue mucus to startle would-be predators. But the males in one group of these “sea fireflies” in the Caribbean use the mucus to create glowing patterns in an elaborate dance to attract mates. To unravel how this talent evolved from a tool of war to a key part of mating rituals, Todd Oakley at the University of California, Santa Barbara, and his colleagues investigated the ostracods’ genetics. They analysed RNA from 45 species of bioluminescent ostracods from around the world, then built an evolutionary tree from the differences between the genes encoding the RNA. This showed how the species were interrelated, and with the help of fossils, it was possible to estimate how long ago the lineages diverged. The researchers found that sea fireflies got their glow roughly 267 million years ago, well before the first dinosaurs. Bioluminescence has arisen in various species in nearly 100 different ways that we know of, including in comb jellies about 350 million years ago, but its emergence in ostracods “is one of the oldest origins of bioluminescence that’s ever been quantified”, says Oakley. The study confirms that ostracods co-opted their defensive glow charges for reproductive ends an estimated 213 million years ago when they split off from their defensively luminous relatives. “We were surprised to find that [the transition] was quite a bit older than we expected,” says Oakley. The Caribbean Sea didn’t fully form until a few million years ago, suggesting that the sea fireflies that use bioluminescence to attract others instead of warding them off possibly got their start somewhere else.
9-13-21 Army ants use temporary bases to store food when raiding insect nests
Army ants are a force to be reckoned with in Central and South American rainforests, frequently raiding other social insects’ nests for vulnerable larvae and pupae. A computer simulation suggests that the insects have come up with a strategy to boost the speed and efficiency of their raids, by temporarily storing the food from a raid in a nearby cache. Hilário Póvoas de Lima at the University of São Paulo in Brazil and his colleagues were observing Eciton hamatum army ants in the Amazon rainforest when they noticed the insects stacking prey that they had pillaged in piles along their foraging trails, far from their bivouac – the nest that houses the queen and larvae and is made out of interlinked bodies of living worker ants. Biologists first noticed these food stacks, or caches, nearly a century ago. They were assumed to appear because ants became stuck in insect traffic jams on their journey back to the bivouac and simply dumped their loads while waiting for the flow issues to resolve. “On the other hand, the biology of army ants told us that timing is essential for them,” says Lima. When a small raiding party is preying on the young in another species’ nest, the element of surprise is important and the entire raid must take place rapidly before the defenders can fight back or evacuate the nest. “We thought that caches may somehow accelerate raiding, making them economically viable for the colony,” says Póvoas de Lima. He and his colleagues generated computer simulations of ant movement during raids and found that raiding ants gathered more food by dumping anything they stole in a cache positioned between a raided nest and their bivouac, then returning to the raided nest to steal more food. However, this advantage worked only as long as the raiding party contained fewer than 100 ants: a larger raiding party didn’t need to cache food for a speedy and efficient raid.
9-13-21 Garden photography reveals a world of hedgehogs and foxes
Ola Maddams has captured striking shots of wildlife at night in her Buckinghamshire garden, using a motion-activated remote camera. With a full-time job in marketing, Mrs Maddams spends her spare time perfecting the art of night photography. "I've also been fascinated by remote-camera photography - a concept where a camera is left deep in the wilderness for weeks, or months, to capture rare and shy animals," she tells BBC News. "Photos captured this way show animals at their most natural and relaxed." Mrs Maddams has taken photographs of wild animals overseas, including lions, leopards and elephants in Kenya's Masai Mara National Reserve. But during coronavirus-lockdown restrictions in 2020, she decided to focus her photographic ambitions on her garden in Amersham, using a passive infrared (PIR) sensor and two flashes. "The sensor reacts to heat, so it triggers the camera when an animal walks past it," she says. "What has always been most important to me is the welfare of my wildlife models - the quest to get the 'perfect' shot should never come at a cost to wildlife. "To make sure the animals are not spooked by the clicking sound of the camera, I place it in a case lined with sound-absorbing foam. "The two flashes are set to the minimal power level and are placed well above the eye level so as not to cause them any distress." Mrs Maddams's interest in garden wildlife began two years ago in a chance encounter. "I was reading a book on the patio and suddenly felt I was being watched," she says. "I saw a small creature on the steps to the garden and immediately thought it was a rat. "When I realised it was a hedgehog, I was over the Moon - the last time I had seen one was when I was 10 years old, in Poland." Encouraged by the sighting, Mrs Maddams and her husband researched the animal and started to leave out cat-food and fresh water. And having bought an infrared trail camera to record video footage, they discovered two hedgehogs, a fox, and a number of local cats, would visit every night. "We learned that just like humans, hedgehogs and foxes are creatures of habit, showing up in our garden at specific times and following certain routines," she says.
9-11-21 Escaped zebras spark double takes and denials in Maryland
They have been on the loose for more than 10 days now - five zebras bringing disbelieving double-takes to the folk of rural Maryland. One youngster got a curt response from her mother until they both looked out the window. The zebras left - no-one is sure how - their private farm enclosure and have since been wandering around for food. One politician known for her opposition to fences around the nearby US Capitol issued a dry denial of involvement. In a statement headlined "Norton Denies Responsibility for Setting Zebras Free, Supports Freedom Generally", Washington DC Congresswoman Eleanor Holmes Norton said that when the zebras escaped she was "enjoying quiet time at home with family". Residents have been given a zebra-spotting number to call, not that they are hard to make out, Even so, Layla Curling, 10, found it hard to persuade her mother. "I thought it was a deer for about three seconds, and then I noticed it was actually a zebra. She said I was crazy and stuff. She believed me after we looked out the bathroom window," Layla told local 7 News. But the animals are a headache to the local animal control officers in Prince George county. Animal services division chief Rodney Taylor said: "'You can't hunt them down. They're just too fast, they run, they won't let you get near them." He also warned they could kick and bite. Mr Taylor said a feeding station had been set up, and the zebras had been seen there in the very early hours of the mornings. It's hoped that when they get comfortable in the surroundings, panels can be put up and the animals will be tranquillised and returned home. Home is a private farm in Upper Marlboro. Some 39 zebras were brought there legally last month. How the five broke out is unknown - there did not appear to be any damage to fencing.
9-10-21 50 years ago, chemical pollutants were linked to odd animal behavior
Excerpt from the September 18, 1971 issue of Science News. For fish and other underwater life, a sensitivity to chemicals plays the same role as the sense of smell does for land animals.… [Researchers] have been studying the subtle ways this delicate fish-communication system can be disrupted by pollutants…. One study examined the effects of kerosene pollution on the behavior of lobsters…. The experiments demonstrate that chemical communication interference takes place at extremely low dilutions. Chemical pollution — from sewage and agricultural runoff to pharmaceutical waste — muddles aquatic animals’ senses with potentially dire effects, decades of research has shown. A chemical used to treat sewage seems to limit some fish species’ abilities to form schools, making the fish vulnerable to predators (SN: 10/27/07, p. 262). Drug-tainted waters can have a variety of effects on fish, including suppressing their appetites (SN: 12/20/08, p. 15). A plastic chemical also appears to confuse senses: Its scent can lure sea turtles into eating plastic debris (SN: 3/28/20, p. 14).
9-10-21 A newfound boa sports big eyes and a square nose
The snake is the first boa species discovered in the Dominican Republic in more than a century. A wide-eyed snake has made scientists do a double take. The Hispaniolan vineboa, with its large protruding eyes and square snout, is the first boa species to be discovered in the Dominican Republic in more than a century. Naturalist Miguel Landestoy of the Universidad Autónoma de Santo Domingo in the Dominican Republic and colleagues discovered the snake, Chilabothrus ampelophis, slithering in a patch of mountainous dry forest near the country’s southwestern border with Haiti on the island of Hispaniola. The last time researchers described a new boa species on the island was in 1888. “The fact that an animal could have gone undetected for so long on this island that has a lot of people on it is pretty remarkable,” says R. Graham Reynolds, a herpetologist at the University of North Carolina Asheville. What’s more, the Hispaniolan vineboa may be among the smallest boas in the world, Reynolds, Landestoy and colleague Robert Henderson of the Milwaukee Public Museum report August 17 in Breviora. Adult boa species typically reach 2 meters or more in length (SN: 10/13/09). The longest Hispaniolan vineboa that the team found, an adult female, measures less than 1 meter. The shortest, probably a juvenile male, is less than a half meter long. Compared with the three other boa species found on the island, the Hispaniolan vineboa’s small size, large eyes and dark, zigzag patterned scales tipped off the researchers that they had spotted something new. Genetic analyses and close inspections five different snakes plus one shed skin confirmed the team’s hunch that the Hispaniolan vineboa is a species new to science. But the species may already be in trouble. All serpents that the team found were within one kilometer of each other. That’s “a little bit alarming in the sense that they might be restricted to a very small area,” Reynolds says. Agricultural activities such as charcoal burning threaten the species’ habitat. The team’s next steps will be to figure out the boa’s true range and how big individuals can get.
9-9-21 A glimpse at Greenland's deep-sea ecosystems threatened by fishing
Sponges and corals living in newly discovered underwater fields and meadows are at risk of destruction as they are continuously raked over by halibut fishing boats off the shores of Greenland. More than a kilometre below the ocean surface, the highly varied ecosystems of the deep sea are home to life forms that thrive on stability. But as fishing boats drag heavy equipment across the ocean floor, they are stirring up chaos in these vulnerable, typically quiet ecosystems. This causes damage that could potentially take decades or centuries to recover from, says Stephen Long at the Zoological Society of London. “Life in the deep sea isn’t used to being disturbed,” says Long. Long and his colleagues equipped a deep-sea sled with cameras to monitor the sea floor around Greenland, where halibut fishing is a critical economic and cultural mainstay. Halibut (Reinhardtius hippoglossoides) live near the ocean floor, so catching them requires nets stretched between pairs of steel braces that scrape along the sea bottom, at depths of up to 1400 metres. The researchers found “extensive physical evidence” of trawling on the sea floor, with visible tracks leaving upturned sand and other sediments in frequently trawled areas, says Long. These areas include “meadows” of cup corals (Flabellum alabastrum) and fields of wand-like sea pens (Halipteris finmarchica). This could mean “serious or irreversible harm to these deep-sea environments”, says Long. To minimise the effects on such vulnerable ecosystems, trawling activity should be restricted to certain areas without expanding into untouched deep-sea regions, he says. “The best management method is to stick with what’s already been trawled,” he says.
9-9-21 Scorpions develop a sting in the tail before they are ready to use it
Newborn scorpions hitch a ride on their mother’s back for protection, and at this early stage in their lives cannot eat, excrete or sting. But scientists have found that they still accumulate venom, enabling them to catch prey and defend themselves as soon as they go it alone after shedding their first exoskeleton. Such speedy development of venom production helps to explain scorpions’ remarkable survival ability since their ancient aquatic ancestors swam the seas more than 400 million years ago, surviving even mass extinction events, say the researchers behind the finding. Songryong Li at Wuhan University in China and his colleagues studied two-day old Chinese scorpions (Mesobuthus martensii), which are translucent and still embryo-like, and found they already had venom stored in the end of their tail, or telson. However, their stinger was blunt and venom exit ducts were blocked, enabling the toxin to pool inside the tail. “It makes sense that they start producing venom so early. It takes a lot of energy and some days to fill venom glands,” says evolutionary biologist Arie van der Meijden at the University of Porto, Portugal, who wasn’t involved in the study. “I imagine the venom gland cells will start producing venom as soon as they are fully [developed].” Li and his colleagues peeled off the outer layer on telson samples with tweezers and observed the sharp stinger had already formed beneath. This would ordinarily be revealed when scorpions naturally moult for the first time around 10 to 20 days after birth, enabling them to inject venom. The scientists also looked at telsons in older, more developed scorpions – which use muscle contractions to control venom release – and found that these animals don’t have blocked venom ducts. This suggests that newborns haven’t yet developed the required muscular control of their venom and so their ducts are initially blocked to prevent venom loss, say the researchers.
9-8-21 Why cutting down on digging the garden can actually be good for soil
OF ALL my garden tools, the one I have used most must be my trusty spade, a lovely small and light one with a comfortable wooden handle. But recently, it has been getting less action because I have been stepping up on the “no-dig” approach to gardening. All gardeners need to dig sometimes, of course, such as when making holes to put plants in or rooting out weeds. Traditional advice is that we should also turn over all the soil every autumn, to aerate it, improve drainage and mix in soil improvers like manure. For the past few years, though, I have been increasingly embracing the no-dig approach. On the allotment, I suppress weeds on bare ground over winter by covering the earth to block out light as much as possible. I used to do this using plastic sheets weighed down with bricks. This year, I have started adopting the system of no-dig advocate Charles Dowding, a UK market gardener and writer. You put down flattened cardboard boxes and cover with some kind of mulch, such as manure or home-made compost. As the cardboard rots, worms take the organic matter down into the soil. This approach may also be better for the soil. Most plants get help in absorbing water and nutrients from a fine network of thread-like fungi on their roots. A large component of these fungal threads is a sticky protein called glomalin, discovered in 1996. Together, the threads and released glomulin make soil clump into bigger particles. If soil is dug over, it breaks up the particles and exposes organic material they contain to decomposition by microbes, releasing carbon dioxide. Soil with larger particles retains more moisture and is less prone to nutrients leaching away. A recent trial in farmers’ fields shows that “no-till” boosts soil glomalin and is also likely to reduce soil erosion. On a smaller scale, Dowding says trials in his market garden show no-dig plots give slightly higher yields of fruit and vegetables – as well as being less work of course.
9-8-21 Animals at London zoo get their annual weigh-in
THESE charming residents of London Zoo, run by the Zoological Society of London, are just a few of the 20,000 animals that are being weighed and measured as part of its annual weigh-in. Recording heights and weights helps zookeepers keep tabs on each animal’s health and well-being, such as whether they are growing at the appropriate rate, as well as to monitor or detect pregnancies. However, since it isn’t always easy getting the animals to remain in one place to be measured, tactics often need to be deployed to get them to stand or stay still. One way to do this is through play. The image above shows Arya, an Asiatic lioness who arrived at the zoo in April, stretching out against a giant ruler after being enticed with a ball. Above, huge callipers are needed to measure Polly the Galapagos tortoise’s shell, while at the other end of the scale, the weigh-in for a midwife toad (below) requires only a spoon-sized instrument.
9-8-21 Rare kakapo parrot is genetically healthy despite being very inbred
A critically endangered flightless parrot in New Zealand has survived as an inbred population for so long that it has fewer harmful mutations than expected. This may be because many of the birds affected by the mutations died out over the past few thousand years. “As far as inbreeding goes, at a population level, what doesn’t kill you makes you stronger,” says Love Dalén at the Centre for Palaeogenetics in Stockholm, Sweden. The findings come from the first genomic study of the kakapo (Strigops habroptilus), only 204 of which are alive. There were once hundreds of thousands of the birds in New Zealand, but their numbers began falling when settlers arrived from Polynesia about 700 years ago and declined more steeply with the arrival of Europeans, who introduced cats, rats and stoats. In the 1970s, kakapo were thought to be extinct, but then 50 were discovered on Stewart Island and were moved to a few smaller sanctuary islands that had been cleared of predators. An intensive conservation programme has turned around their fortunes. Dalén’s team compared the genes of 35 of the sanctuary birds with those of 13 old museum specimens from the mainland plus one found living on the mainland in 1975. The birds on Stewart Island were thought to have been deliberately taken there in the past 500 years, based on historical accounts and an absence of kakapo fossils. In fact, the genetic analysis shows that the birds on Stewart Island and the mainland diverged about 10,000 years ago, suggesting they were already present in the area when rising sea levels cut off the island at that time. As expected, the kakapos living on Stewart Island have less genetic diversity than the mainland birds. But surprisingly, they have an average of 18 potentially harmful genetic mutations per bird, compared with 34 in the museum specimens. This is probably because of a process called “purging”, when communities become so inbred that harmful mutations accumulate and individuals with two mutated copies of a particular gene have fewer offspring.
9-8-21 No, there's nothing wrong with seedless fruits
ONE thing that has always fascinated me is the concept of food taboos. While those of other cultures can seem quirky and colourful to our minds, we can often forget that we have several of our own. These don’t stay still as cultures evolve either, and the introduction of novel foods can often be accompanied by new foodie fears. If my inbox is anything to go by, there is one that seems to be gathering pace in the West: the idea that seedless fruits are dangerous. For those unfamiliar with this belief, it seems to go as follows. The whole biological function of fruit in nature is to distribute the seeds of the plant to ensure the survival of the species. When fruits are seedless, however, it is meant to be a sign that they have been nefariously manipulated to abandon their basic biology by industrial agriculture, rendering them of lower nutritional value. According to more extreme proponents of this view, these fruits not only have an inferior vitamin and mineral content, but are actually harmful. Typing the term “seedless fruit” into an internet search engine presented me with the suggested search terms of “bad”, “bad for you”, “good or bad”, “GMO” and even “bible”. If you are curious about the last one, there appears to be a relatively large section of the internet that views seedless fruits to be against the teachings of the bible and, in particular, anti-abortion beliefs, meaning to some people seedless fruits aren’t just unhealthy, but unethical too. Given the controversy, let’s take a closer look at what seedless fruits are and how they are produced. Seedless fruits are the result of a biological process called parthenocarpy – the development of a fruit without prior fertilisation. While it is true that this can be the result of human actions, it also happens in nature all the time. Often, it is a combination of both.
9-8-21 How metal-infused jaws give some ants an exceptionally sharp bite
Body parts reinforced with zinc and manganese make impossible cuts possible, a study suggests. If you’ve ever felt the wrath of a biting or stinging insect, it may seem incredible that something so small can so easily slice or puncture human skin. Scientists already knew that some small animals’ piercing and slashing body parts are infused with metals such as zinc and manganese, making the parts tough and durable. Now, a study published September 1 in Scientific Reports shows how these toollike appendages form hard and extremely sharp cutting edges. Robert Schofield, a physicist at the University of Oregon in Eugene, and colleagues used a special microscope to examine the sharp “teeth” that line the jaws of leaf-cutting ants called Atta cephalotes, revealing the teeth’s atomic structure (SN: 11/24/20). The team found that zinc atoms were dispersed homogeneously, rather than in chunks, throughout a single tooth. This uniformity allows the ants to grow much thinner, sharper blades, since “chunks of mineral limit how sharp the tool can be,” Schofield says. The team also tested a suite of properties of these metal-infused materials, known as heavy element biomaterials, in ant teeth, spider fangs, scorpion stingers and marine worm jaws, among others. These structures are stiffer and more damage-resistant than biomineralized materials, like the calcium phosphate typically found in teeth or the combination of calcium carbonate and the protein chitin in many arthropod shells, the team found. The metal-fortified body parts have “the kinds of properties that you want in a knife or needle,” Schofield says. The team estimates that the zinc-infused teeth of A. cephalotes allow it to puncture and cut using only about 60 percent of the energy and muscle mass it would otherwise.By making these sharp, precisely sculpted tools, ants and other small animals can make up for their tiny muscles, allowing them to acquire and process foods that would normally be beyond their reach.
9-8-21 Cold plasma could transform the sustainable farms of the future
How the fourth state of matter can make a greenhouse greener — and boost plant growth. Physicist Stephan Reuter of Polytechnique Montréal spends most days using his expertise in energy and matter to improve medical technologies. Recently though, he stood in a sea of green to consider how a shower of charged particles might affect lettuce. He had been invited to one of the largest commercial greenhouses in Quebec to help the growers rethink the energy of agriculture. Inside the building, encased by glass walls and covering more ground than four soccer fields, thousands upon thousands of lettuce plants floated on polystyrene mats in a hydroponic, or no-soil, growing system. The crop was nearly ready to be picked, packaged and shipped. Reuter’s task was to use physics to help the company, Hydroserre Inc. in Mirabel, reduce its carbon footprint. To that end, the company is interested in finding new ways to fight pathogens and to deliver fertilizer to the growing plants. Many fertilizers contain ammonia, which is produced from nitrogen (necessary for plant growth) and hydrogen using a chemical reaction called the Haber-Bosch process. This process revolutionized agriculture in the early 20th century by making mass production of fertilizer possible. However, the process yields hundreds of millions of metric tons of carbon dioxide each year. “Ideally, we want a fertilizer that’s renewable,” Reuter says. And to make it truly green, it should be created at the farm, making transport, another carbon emitter, unnecessary. Reuter and a growing number of chemists, physicists and engineers think they can see how to make that happen. These researchers are working toward future farms that are truly sustainable, where the energy from renewable sources like wind or solar is harnessed to make an efficient fertilizer on-site. They hope to realize this vision by exploiting plasma.
9-7-21 Foam from frogs' nests could help make bandages that release drugs
The foam that some frogs produce to make nests could be a good candidate for future pharmaceuticals and cosmetics because it can keep its shape for more than a week, isn’t likely to irritate human skin and can slowly release drugs for days. Most synthetic and natural foams – like medical foams, beer foam, and the “spit” left on grass by insects called leafhoppers – collapse into a liquid within minutes or hours. But some frogs produce an incubator foam – protecting eggs and tadpoles from germs, dryness, and sun rays – so robust, it can withstand 10 days of harsh tropical conditions, says Paul Hoskisson at the University of Strathclyde in Glasgow, UK. To investigate the foam, Hoskisson and his colleagues collected about 200 whole foam nests from wild túngara frogs (Engystomops pustulosus) and removed the eggs for safekeeping. They ran protein analyses and various kinds of spectroscopy on the foam, confirming earlier findings that it has six differently sized proteins, which create what the researchers call “clamshell-like” structures. The structures include “water-loving and water-repellent” sides allowing them to hold liquid inside the foam, says Hoskisson. Force testing revealed that the foam could withstand remarkably high shear stress – 100 pascals, or about as strong as a 45 kilometre per hour wind – before breaking down. By comparison, stiffly peaked egg white foam can only withstand about half that force, he says. To see if the foam could work in human medicine, the researchers incubated human skin cells with foam fluid and found no toxicity, says Hoskisson. Next, they loaded different kinds of dyes and an antibiotic, rifampicin, into the foam to measure time-release abilities. The foam released the compounds slowly, over periods of between two and seven days – in stark contrast to the hours or even minutes of extended drug release provided by current medical foams, he says.
9-7-21 Polar bears in Svalbard archipelago are inbreeding due to sea ice loss
As global warming causes Arctic ice to melt , archipelago-based polar bears are having more difficulty reaching each other, especially during mating season, resulting in what researchers have dubbed an “alarming” drop in gene flow and genetic diversity due to inbreeding. A team at the Norwegian Polar Institute in Tromsø have been collecting small tissue samples from polar bears (Ursus maritimus) inhabiting Svalbard’s islands in the Barents Sea since 1995. Most of these bears usually roam across sea ice throughout the archipelago and often mate with bears in other regions. In recent decades, however, global warming has led to a rapid drop in the extent and the thickness of sea ice cover – in particular on the westernmost island, Spitsbergen. It has also caused the winter ice to melt earlier in spring, encroaching on the animals’ breeding season. “If there’s still ice, bears will move across quite easily. But as soon as the ice melts, and it’s now vast ocean waters, that oceanic water is a barrier,” says Simo Maduna at the Norwegian Institute of Bioeconomy Research in Svanvik. To understand the effect of this on polar bear genetics, Maduna and his colleagues analysed the DNA of 622 bears, representing four geographical regions of the archipelago: north-west, north-east, south-west and south-east. They found that genetic diversity has dropped since the mid-1990s, by as much as 10 per cent in the most affected region – the north-west – suggesting that the bears are mating more locally than before. In addition, the bears have started to form genetic subpopulations, with a significant amount of genetic differentiation from one region to another. Again, it was the most affected region – the north-west – where the changes were most substantial, according to the researchers.
9-7-21 Gene responsible for cat fur patterns could lead to designer pets
How do tabby cats get their stripes? We know that domestic cats have different colours of fur because hair follicles produce different types of the pigment melanin, but until now the genetic basis for these patterns has been unclear. The discovery could potentially allow for designer pets. “It’s this really amazing natural phenomenon and we don’t know, or we didn’t know, much about how it came about or how evolution had changed it over time,” says Gregory Barsh at the HudsonAlpha Institute for Biotechnology in Alabama. “Why does the tiger have stripes and the cheetah have spots? How does evolution act on those on a common mechanism to give rise to different patterns?” To learn more, Barsh and his colleagues examined fetal cat skin from embryos at different stages of development obtained from feral cat spay-neuter clinics. They noticed that embryonic skin was divided into alternating thick and thin regions, which they later discovered corresponded to hair follicles that produce different types of melanin. Through analysing the gene expression of individual fetal cat skin cells at different levels of development, the team determined that embryonic differences in the expression of the gene Dkk4 give rise to variations in the shape of cat fur colour patterns. These findings may also apply to other mammals with patterned fur, says Barsh. “Most of the coat colour discoveries in mammals are performed in mice, and mice don’t have spots and stripes. So, for several years now, we’ve been saying that domestic cats could be a good model,” says Eduardo Eizirik at the Pontifical Catholic University of Rio Grande do Sul in Brazil. “Just finding the gene by itself is a major contribution because we can now look at the gene in other species.” “Domesticated cats have undergone selective breeding throughout many generations, so it remains to be seen whether the molecular processes uncovered here also explain natural variation in wild felid species,” says Ricardo Mallarino at Princeton University in New Jersey.
9-6-21 Saving Australian frog species on the brink of extinction
Scientists have identified 26 frog species in Australia which are at risk of extinction by 2040. Four species are likely to be already lost but urgent efforts could save others, they say.
9-5-21 Listen to an Australian duck say ‘you bloody fool’ like a human
Adult musk ducks raised in captivity can mimic the sounds they heard as hatchlings, such as a pony snorting, a door slamming, a man coughing and even what was probably a former caretaker’s catchphrase, “You bloody fool!” The large, grey Australian waterbirds usually learn to make high-pitched whistles from their older flock mates. But individuals raised in captivity away from other musk dusks have been heard copying the sounds around them associated with human life. The findings provide evidence that musk dusks (Biziura lobata) now join parrots, hummingbirds, certain songbirds, whales, seals, bats, elephants and humans (but not other primates) as vocal language learners, which means they acquire “utterances” based on what they hear as infants, says Carel ten Cate at Leiden University in the Netherlands. “Vocal learning is a rare and special trait, so that makes this duck particularly special,” he says. Ten Cate studies vocal learning in birds and was recently fascinated to stumble across a vague story about a talking duck in Australia. So he tracked down the now-retired Australian scientist Peter J. Fullagar, who first noticed the phenomenon more than 30 years ago. Fullagar shared his conserved audio clips of 4-year-old Ripper, a male musk duck hand-raised on a nature reserve without other musk ducks. In the clips, Ripper waddles and splashes around speaking swear words when acting aggressively and imitating a slamming door sound when trying to attract females. Fullagar also shared an audio clip of a second male that was raised on the same reserve with his mother in 2000, along with Pacific black ducks (Anas superciliosa) that quack “like common park ducks,” ten Cate says. Female musk ducks don’t perform vocal displays, and the young, unnamed duck grew up to imitate the quacking black ducks around him.
9-4-21 Tuna bounce back, but sharks in 'desperate' decline
Tuna are starting to recover after being fished to the edge of extinction, scientists have revealed. Numbers are bouncing back following a decade of conservation efforts, according to the official tally of threatened species. But some tuna stocks remain in severe decline, said the International Union for the Conservation of Nature (IUCN), which compiles the extinction Red List. It said pressures on marine life are continuing to grow. And almost four in ten sharks and rays are now threatened with extinction. Meanwhile, on land, the Komodo dragon is moving closer to oblivion. The heaviest lizard on Earth faces threats from climate change, with fears its habitat could be affected by rising sea levels. The revised list of the world's endangered plants and animals was released at the start of the world's leading conservation congress, which is taking place in the French city of Marseille from 3 to11 September. The news is a "powerful sign" that despite increasing pressure on our oceans, species can recover, if states commit to sustainable practices, said IUCN Director General, Dr Bruno Oberle. Those gathered for the IUCN World Conservation Congress "must seize the opportunity to boost ambition on biodiversity conservation", he said. The IUCN Red List of Threatened Species is the "gold standard" for measuring how close animal and plant species are to dying out. Some 139,000 species have been assessed over the last half-century, with nearly 39,000 now threatened with extinction, while 902 have gone extinct. The latest update - the second this year - revealed encouraging signs for four of seven tuna species. Tuna stocks in some areas remain of concern, such as bluefin tuna in western parts of the Atlantic and yellowfin in the Indian Ocean. "The take home message for the general public is that things like albacore tuna - which is the one that is widely on supermarket shelves - is of least concern now - it means that what they're eating has been sustainably caught and is well managed," Craig Hilton-Taylor, who heads the IUCN Red List, told BBC News.
9-3-21 Male bigfin reef squid may be the best fathers of all
The standard for good cephalopod fathers might be a pretty low bar, but bigfin reef squid swim right over it. Male cephalopods, such as squids and octopuses, are not known for their parenting due to the fact that they often die soon after mating – but some species of squid might be the exception to this rule, as they have now been seen investigating potential nest sites to make sure they are safe before their female counterparts lay eggs. Typically, female cephalopods are left to care for their eggs alone. “Usually, the only thing the male does before and after mating is mate guarding,” says Eduardo Sampaio at the University of Lisbon in Portugal. After a male courts a female and mates with her, his only other job is to guard her against the sperm of rival males. But this might not be the case for some squid species. Sampaio and his collaborator, Samantha Cheng at the American Museum of Natural History, filmed squid mating rituals at two sites, one in the Red Sea and the other off the coast of Indonesia. In their recordings, a male squid (Sepioteuthis lessoniana) that has just mated raises his arms up while pushing his tentacles downward. At the same time, he dons a color pattern similar to animated zebra stripes. “This is really awkward for the squid, because the tentacles are usually held with the arms to protect them,” said Sampaio, “But the whole display is really obvious for other males to see.” After the zebra display but before his mate lays her eggs, he dives into a crevice in a reef or rocks on the seafloor, possibly checking for signs of predators. “Typically, the male just copulates and goes, but here we saw that he actually checks out the nest site first,” said Sampaio. “Only then does the female enter the location.” He does this at the risk of predators lying in wait and of rival males sweeping in on his unguarded mate. “One cool thing to consider is that we were able to document this behaviour in populations 10,000 kilometers apart from each other,” said Sampaio. This suggests the behavior is rather widespread among bigfin reef squids.
9-3-21 Zebras rolling in pits help give life to the Namib desert in Africa
. Rolling on the ground seems to be essential to life – at least in Africa’s Namib desert, where zebras bathe in dust, creating pits in the landscape that promote biodiversity. The Namib desert is a vast stretch of dunes and mountains along the coasts of Angola, Namibia and South Africa. It is the world’s oldest desert and one of the driest. Despite this extreme aridity, many animals and plants have adapted to survive, including the Hartmann’s mountain zebra (Equus zebra hartmannae). Herds live on the mountainous desert edge, migrating with rainfall. The zebras often roll in the dusty ground to groom and get rid of parasites. As part of this process, they hoof out large stones and displace the soil, making comfortable spots in which they rest and leave dung. These pits can reach up to 30 centimetres deep and can last for years. Thomas Wagner at the Technical University of Munich, Germany, wondered if there were ecological benefits to this accidental landscaping. Over five consecutive rainy seasons, Wagner and his team calculated vegetation cover from drone images in more than 650 rolling pits, tracking the greening and wilting of the landscape following rains. They sampled soil and plant composition in 16 of the pits, using surrounding grassland as controls. The researchers found rolling pits were mostly composed of finer soil and sand, instead of gravel. This allows rainwater to filter into the soil roughly twice as deeply as in nearby grassland, collecting like a pond and keeping the soil moist for longer. Levels of nitrogen and phosphates were higher too, probably because of the dung. The rolling pits were greener for longer, and were dominated by forbs — flowering plants — in place of perennial grasses. More plant-eating arthropods like short-horned grasshoppers and butterflies appeared, too. Local farmers often see zebras as a problem, says team member Kenneth Uiseb at the Namibia Ministry of Environment, Forestry and Tourism. “This project highlights the importance of zebras in ecosystem engineering, and the potential benefits they bring to the landscape.”
9-3-21 Breeding seabird numbers in Scotland almost halved since 1980s
The number of breeding seabirds in Scotland has declined by almost half since the 1980s, according to a new report. The figures are included in NatureScot's latest biodiversity indicator, which looked at 11 species of breeding seabirds. The results show that numbers fell by 49% between 1986 and the most recent estimate in 2019. Arctic skua numbers dropped by 81% and the number of common terns fell by 48%. However, guillemot numbers have increased by 17% since 2016. Reductions in the availability of sandworms and increased predation from great skuas are believed to have led to the sharp reduction in Arctic skua numbers. NatureScot said other species, including herring gulls, appear to be stabilising, albeit at lower levels than the 1986 baseline year. NatureScot's trends and indicator analyst Simon Foster said "internationally-important" breeding seabird populations were continuing to decline despite "some positive signs of stabilisation." He said: "We know that these declines are driven by factors including climate change, fisheries and invasive non-native species. "The Scottish government's forthcoming Scottish seabird conservation strategy will be a crucial step in shedding more light on the pressures and threats that our seabirds face and setting out action to help secure their future."
9-2-21 Stingrays’ bulging eyes and mouths make them much faster swimmers
With their smooth, flexible fins, stingrays are extraordinarily efficient swimmers – but their eyes and mouth stick out, which intuitively seems like it would create drag and slow them down. It turns out that these bulging faces have the opposite effect, allowing stingrays to swim even faster and more efficiently. Hyung Jin Sung at the Korea Advanced Institute of Science and Technology in South Korea and his colleagues investigated how the protruding eyes and mouths of stingrays affect how they move through the water using a series of hydrodynamic simulations. Some of the simulated rays had eyes and mouths, some only had one or the other, and some were completely smooth. They found that the protrusions created a set of vortices as the water moved over them. One vortex pushed water towards the back of the ray, leaving an area of lower pressure in front of it. This low-pressure zone allowed the simulated rays to swim faster. Another vortex sloshed water to the sides, increasing the pressure below the ray and decreasing the pressure above it. This made each stroke of the fins generate more thrust, increasing the efficiency of swimming. Sung says that he was “very surprised” at these results, particularly at the magnitude of the effect – the analysis showed that stingrays’ eye protrusions increased their propulsion efficiency compared to rays without these features by about 20.5 per cent, and their mouth increased it by about 10.6 per cent. These vortices only appear because the rays have bendy bodies with rigid eyes and mouths, says Sung. Similar effects may help other flexible, self-propelling animals move more quickly as well. He and his team are now trying to incorporate this knowledge into designs for efficient water vehicles that mimic the motions of sea creatures.
9-2-21 Cavalier King Charles spaniels carry a high number of harmful genes
Dog breeding has produced canines in a variety of shapes and sizes, but has also led to a build-up of harmful mutations in certain breeds. A new study suggests that cavalier King Charles spaniels carry a particularly high level of mutations, including variants linked to a heart condition called myxomatous mitral valve disease. Erik Axelsson at Uppsala University in Sweden and his colleagues compared the sequenced genomes of 20 individual dogs from eight popular dog breeds, such as German shepherds and golden retrievers, and found that cavalier King Charles spaniels had the highest number of potentially harmful variants of genetic mutations. The team also looked for genetic variants that might explain why cavalier King Charles spaniels are particularly likely to develop a heart valve condition called myxomatous mitral valve disease, which affects nearly 100 per cent of 11-year-old cavalier King Charles spaniels. They found six variants in the heart-specific NEBL gene that seemed to be correlated with the condition in the spaniels – and three of the variants were also associated with early onset of the heart condition in a second dog breed, dachshunds. In what way these variants might be harmful is unknown. While they may cause disease, it could also be that they don’t really have much of an effect on dogs today because we are more able to take care of their health than we were in the past, says Axelsson. The finding may be related to the fact that dog breeds often begin when humans selectively breed dogs taken from a small group with a desired set of traits, he says. It could be that the negative variants were unintentionally selected along with the genes responsible for the desired qualities. “If populations – whether in the wild or domestic animals – are too small, you actually run the risk of accumulating these harmful variants,” says Axelsson. “When a population is small, it’s harder for natural selection to filter out harmful variants.”
9-2-21 Some wasps’ nests glow green under ultraviolet light
Fluorescent homes may help wayward insects find their way in the dim twilight. Beam a black light into some Vietnamese forests at night, and brilliant green bulbs may glow in the trees. These eerie lanterns are the nests of several species of Asian paper wasps, and the gleam comes from silk fibers in the nests that fluoresce when struck by ultraviolet light, researchers report in the August Journal of the Royal Society “When you see it, it’s just magic,” says chemist Bernd Schöllhorn of the Molecular Electrochemistry Lab at the University of Paris and CNRS. Schöllhorn and colleagues discovered the nests while searching forests in Vietnam for fluorescent insects using powerful UV torches. “It looked like somebody turned on a flashlight in the forest, but nobody was there,” he says. Fluorescence occurs throughout the animal kingdom. Platypuses, scorpions and polka dot tree frogs, for example, all fluoresce under UV light (SN: 11/6/20; SN: 4/3/17). After analyzing the fluorescence of the nests of some Asian paper wasps (Polistes spp.) in the lab, the researchers found that silk threads in the nests glow more brilliantly than other documented fluorescent biomaterials. The nests of one wasp species, P. brunetus, emitted about one-third as much light as they absorbed. And in some cases, the nests were visible by the naked eye from up to 20 meters away. “We haven’t seen any other example like that,” Schöllhorn says. The fluorescence must benefit the wasps somehow, the researchers say, though it’s unclear how. One hypothesis is that the nests protect larvae inside from UV radiation by absorbing some of the harmful energy and dissipating it as visible light, Schöllhorn says (SN: 10/13/20). Or, as the sun casts its last UV light at the end of the day, the nests might shine bright enough amid the darkening foliage to help wayward wasps find home, like beacons at twilight.
9-1-21 Illegal cannabis farms on the US west coast are poisoning wildlife
Cannabis crops grown illegally on public lands along the west coast of the US are infringing on the habitats of native species, putting predators at risk of poisoning by dangerous pesticides. Greta Wengert at the Integral Ecology Research Center in Blue Lake, California, first got an inkling of the scale of this human-wildlife conflict when cat-sized, ferret-like mammals called fishers (Pekania pennanti) turned up fatally poisoned by rodenticides. This was a surprise, considering the animals’ usual habitats are far from human developments. Wengert and her colleagues suspected that the rodenticide was coming from illegal cannabis farms, where the poison is often used to control pests, because this is one of the few major potential sources of the poison in the region’s forested wilds. To probe whether it was happening, the team used modelling to predict where illegal cannabis farms and three different threatened predators – fishers, Humboldt martens (Martes caurina humboldtensis), and northern spotted owls (Strix occidentalis caurina) – would be most likely to intersect. The team gathered law enforcement data from 1469 illegal cannabis cultivation sites in northern California and southern Oregon from 2007 to 2014. Using the environmental characteristics of the sites, the team made maps of where people were most likely to illegally grow cannabis, then compared these maps with similar models of suitable habitat for the three predator species. Areas with a moderate-to-high likelihood of cannabis cultivation overlapped with more than 44 per cent of fisher habitat, and about 48 per cent of spotted owl and 40 per cent of Humboldt marten habitats, suggesting that the animals’ risk of pesticide exposure is high. When the team surveyed some of the areas predicted to have a higher likelihood of hosting cannabis farms, 16 previously unknown sites were uncovered, validating the model’s predictive potential.
9-1-21 One in three trees face extinction in wild, says new report
At least 30% of the world's tree species face extinction in the wild, according to a new assessment. They range from well-known oaks and magnolias to tropical timber trees. Experts say 17,500 tree species are at risk - twice the number of threatened mammals, birds, amphibians and reptiles combined. Conservation groups are calling for urgent protection efforts amid threats such as deforestation, logging and climate change. "We have nearly 60,000 tree species on the planet, and for the first time we now know which of these species are in need of conservation action, what are the greatest threats to them and where they are," said Dr Malin Rivers of the charity Botanic Gardens Conservation International in Kew, London. For a healthy world, we need tree species diversity, added Sara Oldfield, co-chair of the Global Tree Specialist Group of the International Union for the Conservation of Nature. "Each tree species has a unique ecological role to play," she said. "With 30% of the world's tree species threatened with extinction, we need to urgently scale-up conservation action." The report, State of the World's Trees, found that at least 30% of the 60,000 known tree species face extinction. Some 142 species have already vanished from the wild, while 442 are on the very edge of extinction, with fewer than 50 individual trees remaining. The biggest threats to trees globally are forest clearance for crops (impacting 29% of species), logging (27%), clearance for livestock grazing or farming (14%), clearance for development (13%) and fire (13%). Climate change, extreme weather and sea level rise are growing threats to trees. But the authors say with conservation action, there is hope for the future. "The report gives us that road map to mobilise the wider conservation community and other key players to ensure that tree conservation is at the forefront of the conservation agenda," said Dr Rivers.