10-31-19 Female Asian elephants mysteriously stop reproducing later in life
Female Asian elephants stop reproducing towards the end of their lives, putting them among a very small number of species that experience something akin to the menopause. Only humans, orcas, narwhals, beluga whales and short-finned pilot whales are known to exhibit what biologists call extended post-reproductive lifespan. The existence of such a stage is an evolutionary riddle: why should individuals give up trying to leave more descendants? Simon Chapman at the University of Turku, Finland, and his colleagues studied records of 3802 female Asian elephants that worked in timber camps in Myanmar between 1940 and 2018. This population is considered semi-captive as humans don’t intervene in their reproduction and their mortality and fertility patterns are similar those of to wild elephants. The oldest elephants in this group live into their 70s, but most have had their last calf by age 55. The researchers calculate that the proportion of years lived by females in a post-reproductive phase is 16 per cent: some way short of humans’ 43 per cent but considerably more than African elephants’ 4 per cent. Although their fertility declines in the later stages of life, there is no cut-off point at which reproduction becomes impossible, as it does in humans. In elephants, the cessation of reproduction may be determined by behaviour, rather than physiology, says Chapman. “We think it’s more of a social thing.” It could be that this behavioural trait is a first step towards evolving a true menopause. One prominent idea to explain why females might stop having offspring some time before the end of their lives is known as the grandmother hypothesis. If older females help care for their grandchildren, the theory says, they end up leaving more descendants than if they have more children of their own. There is some supporting evidence from studies of human populations before people had access to modern medicine.
10-31-19 Spiders inspire double-sided sticky tape to heal wounds
A double-sided tape designed to stick body tissue together after surgery has been inspired by the way spiders exude "glue" to catch their prey in the rain. Scientists at Massachusetts Institute of Technology noticed how the spiders' secretion absorbed water, helping to secure their next meal. The sticky tape does the same and was found to work within seconds in tests on pig skin and lungs. The team said with more research, it could be used in place of sutures. But they are still several years away from trials in humans. Getting tissues in the body to form a tight seal is difficult because water on their surface makes them slippery. Sutures - stitches that hold a wound or cut together - don't always work well and can cause infections and pain. And tissue glues, which already exist, can take several minutes to work and may drip on to other body parts. So the scientists turned to nature for inspiration. Spiders secrete a sticky material containing charged polysaccharides that absorb water from the surface of an insect almost instantaneously, leaving a small dry patch the glue can then stick to. And, similarly, the researchers used polyacrylic acid on the tape to absorb water from wet body tissues, which then activated the glue to stick fast. Adding gelatin or chitosan, can make the tape hold its shape for a few days or a month depending on how long it needs to last, the researchers say. They have now tested it out on different types of rat and pig tissue, including small intestine, stomach, liver and skin. Study author Hyunwoo Yuk said: "It's very challenging to suture soft or fragile tissues such as the lung and trachea - but with our double-sided tape, within five seconds we can easily seal them." It could potentially also be used to attach medical devices to organs such as the heart "without causing damage or secondary complications from puncturing tissue". The researchers now plan to perform more tests on animals. The study is published in Nature.
10-30-19 'Alarming' loss of insects and spiders recorded
Insects and spiders are declining in forests and grasslands across Germany, according to new research. Scientists have described the findings as "alarming", saying the losses are driven by intensive agriculture. They are calling for a "paradigm shift" in land-use policy to preserve habitat for the likes of butterflies, bugs and flying insects. Recent studies have reported widespread declines in insect populations around the world. The latest analysis, published in the journal, Nature, confirms that some insect species are being pushed down the path to extinction. It is becoming clearer and clearer that the drivers of insect decline are related to farming practices, said Dr Sebastian Seibold of the Technical University of Munich in Freising, Germany. "Our study confirms that insect decline is real - it might be even more widespread then previously thought considering, for example, that also forests are experiencing declines in insect populations," he told BBC News. "I think it's alarming to see that such a decline happens not only in intensively-managed areas but also in protected areas - so the sites that we think are safeguarding our biodiversity are not really working anymore." The research team recorded data on more than a million individual insects and spiders (2,700 different species) at hundreds of grassland and forest sites in three regions of Germany between 2008 and 2017. They found that a marked decline in abundance and the number of species in both grasslands and forests, with the main drivers (at least for grasslands) associated with intensive agriculture. Many other studies in recent years have shown that individual species of insects, such as bees, have suffered huge declines, particularly in developed economies. However, some insect species, such as houseflies and cockroaches, appear to be on the up.
10-30-19 Parasites are going extinct in droves – and we should be very worried
They cause deadly diseases and brainwash crickets to leap into ponds, so why are conservationists fighting to save parasites from extinction? IN 1987, officials from the US Fish and Wildlife Service captured all 22 of the world’s remaining California condors in a last-ditch effort to save the species. Back at San Diego Wild Animal Park and Los Angeles Zoo, biologists liberally dusted them with an insecticide called carbaryl to remove any parasites. The condors emerged from the blizzard unscathed, and the captive breeding programme was so successful that, by 1991, conservationists began returning birds to the wild. The California condor louse didn’t fare so well. With a few shakes of powdery pesticide, the parasite quietly went extinct. Few people noticed and even fewer cared. If saving this iconic bird meant losing a louse, so be it. Such attitudes still prevail. But perhaps not for much longer. While parasites can harm and even kill their hosts, there is also a growing appreciation of their value. Far from being organisms that must be eradicated at any cost, it is emerging that they play important and beneficial roles in ecosystems. They can even keep their hosts healthy. In fact, in a modern parallel to the California condor story, conservationists trying to save an endangered marsupial called the woylie have discovered that parasites can actually help. Despite this, many parasites are themselves endangered and their plight has been almost completely overlooked. Now a group of pioneering biologists aims to change that. They see parasites as an essential component of life on Earth and believe we should be protecting them. There is no doubt that parasites have a bad reputation. For most people, they are synonymous with disease. This reflects our daily interactions with them. We treat our pets for heartworm and ringworm or take precautions for ourselves against hookworm. We douse our crops in torrents of chemicals to prevent parasites from ruining our food. It is almost dogma that parasites are bad, end of story, says Kevin Lafferty at the University of California, Santa Barbara. Even biology textbooks focus on the negative./p>
10-30-19 Spider webs don’t rot easily and scientists may have figured out why
Bacteria key to decomposition can’t get at the silk’s nitrogen, a nutrient needed for growth. From spooky abandoned houses to dark forest corners, spider webs have an aura of eternal existence. In reality, the silk threads can last hours to weeks without rotting. That’s because bacteria that would aid decomposition are unable to access the silk’s nitrogen, a nutrient the microbes need for growth and reproduction, a new study suggests. Previous research had hinted that spider webs might have antimicrobial properties that outright kill bacteria. But subjecting the webs of three spider species to four types of bacteria revealed that the spiders use a resist strategy instead, researchers report October 23 in the Journal of Experimental Biology. The scientists “challenge something that has gone significantly overlooked,” says Jeffery Yarger, a biochemist at Arizona State University in Tempe, who wasn’t involved in the research. “We just assumed [the silk] has some kind of standard antimicrobial property.” Spiders spin strings of silk to trap food, wrap their eggs and rappel. Their silk webs can sport leaf debris for camouflage amidst tree canopies or leftover dead insects for a meal later. These bits and bobs lure bacteria and fungi involved in decomposition to the web, exposing the protein-rich web silks to the microbes. “But [the microbes] don’t seem to affect spider silk,” says Dakota Piorkowski, a biologist at Tunghai University in Taichung, Taiwan. To check if the silk was lethal to bacteria, Piorkowski’s team placed threads from three tropical spider species — giant golden orb weaver (Nephila pilipes), lawn wolf spider(Hippasa holmerae) anddome tent spider (Cyrtophora moluccensis) — in petri dishes and grew four types of bacteria, including E. coli, in perpendicular lines across the silk. “The idea is that if the silk has antibacterial properties, you should see no growth between the piece of silk and … bacteria,” Piorkowski says.
10-30-19 Saharan silver ants are the world’s fastest despite relatively short legs
At top speeds, these scavengers basically gallop, with all six legs in the air at once. The world’s newly crowned fastest known ants don’t look as if they’ve got the legs to be champs. Saharan silver ants (Cataglyphis bombycina) have merely runner-up proportions, with legs about 18 percent shorter than those of a related desert ant (C. fortis). Yet adjusting for body length, video shows silver ants rushing along about twice as fast as their leggier cousins. Sarah Pfeffer of the University of Ulm in Germany and colleagues took a high-speed video camera to Tunisia to get that video of the shorter ants in their hot and sandy home. At an oasis on the northern edge of the great dunes, the researchers searched for glimpses of silver. Tiny silver hairs coat the ants, reflecting some of the sun’s glare and shedding heat (SN: 6/22/15). When Pfeffer, an applied neuroethologist, digs out a nest to study, several thousand ants seething in her transport box look “like quicksilver,” she says. That silvery protection comes in handy because the ants stay in their nests at night and scavenge for food in the furnace of midday. “The sun really burns down,” Pfeffer says. Surface sand temperatures can soar over 60° Celsius (about 140° Fahrenheit). Even at ant heights, the air is still brutal. Silver ants, however, get two bonuses for foraging in the worst of the heat. It’s a great time to find fresh carcasses of creatures that the sun fried but that heat-averse scavengers haven’t found yet. Also, ant-hungry predators often take shelter from the heat, so silver ants are less likely to become lunch themselves.
10-28-19 Bird eggs laid in cold climates are darker, which may keep eggs warm
A global survey of bird egg color reveals a simple trend: the colder the climate, the darker the egg. Bird eggs come in a dizzying array of colors. But from a global perspective, that diversity follows a simple pattern — the colder the climate, the darker the egg, new research shows. Darker eggs absorb more heat than lighter ones, which could help developing chicks stay warm while their parents forage for food, according to the study published online October 28 in Nature Ecology and Evolution. Biologists have long tried to suss out the selective forces that shape and color a specific species’ eggs. Those forces include keeping eggs hidden from predators, protecting them from bacteria, signaling egg quality and maintaining egg warmth. “All of these hypotheses have some level of [evidential] support,” says Phillip Wisocki, who worked on the research while studying biology at Long Island University Post in Brookville, New York. But scientists weren’t sure whether any of these factors were important in determining egg diversity globally. “If your focus is too narrow, you can miss a lot of what’s going on,” says Wisocki’s adviser, biologist Daniel Hanley. Using museum collections of bird eggs, Hanley, Wisocki and their colleagues compiled data on eggs from 634 bird species from 36 of the 40 living orders of birds. They then analyzed the data against a global map, and found that the brightness and color of eggshells closely correlated with temperature, even after correcting for color similarities between closely related species. Birds in “the far north, which tends to be colder, had darker, browner eggs,” Hanley says. Eggs became lighter and slightly bluer for birds living closer to the equator, though egg colors were generally more variable in the tropics.
10-26-19 Migrating Russian eagles run up huge data roaming charges
Russian scientists tracking migrating eagles ran out of money after some of the birds flew to Iran and Pakistan and their SMS transmitters drew huge data roaming charges. After learning of the team's dilemma, Russian mobile phone operator Megafon offered to cancel the debt and put the project on a special, cheaper tariff. The team had started crowdfunding on social media to pay off the bills. The birds left from southern Russia and Kazakhstan. The journey of one steppe eagle, called Min, was particularly expensive, as it flew to Iran from Kazakhstan. Min accumulated SMS messages to send during the summer in Kazakhstan, but it was out of range of the mobile network. Unexpectedly the eagle flew straight to Iran, where it sent the huge backlog of messages. The price per SMS in Kazakhstan was about 15 roubles (18p; 30 US cents), but each SMS from Iran cost 49 roubles. Min used up the entire tracking budget meant for all the eagles. The Russian researchers are volunteers at the Wild Animal Rehabilitation Centre in Novosibirsk. Their crowdfunding appeal, which has paid off more than 100,000 roubles (£1,223), was called "Top up the eagle's mobile". The SMS messages deliver the birds' coordinates as they migrate, and the team then use satellite photos to see if the birds have reached safe locations. Power lines are a particular threat for the steppe eagles, which are endangered in Russia and Central Asia. They are currently tracking 13 eagles. The birds breed in Siberia and Kazakhstan, but fly to South Asia for the winter. Megafon's offer to bail out the team, reported by RIA Novosti news, means they can continue monitoring the eagles' routes, collecting vital data to help their survival.
10-25-19 Brexit: Will the Falkland Islands wildlife suffer?
Squids, penguins and elephant seals. No, not a scene from a David Attenborough series, but just some of the wildlife that live in the Falkland Islands. But local conservationists are worried that the Falklands will not have enough resources to protect its environment after the UK leaves the EU. "We might stop being able to protect the amazing wildlife," Michelle Winnard, a local conservationist, tells Radio 1 Newsbeat. The Falkland Islands sit in the south-west Atlantic Ocean - and remains the subject of a dispute between Britain and Argentina who fought a war over it in 1982. It held a referendum in 2013 and opted to remain an overseas UK territory - which means the Falklands are self-governing - but the UK is still responsible for foreign and defence matters. The Falkland Islands did not get a vote in the 2016 EU referendum. After the result was announced, the government said it would work with the UK government to achieve a good deal for the Falkands. Michelle, 28, works for Falklands Conservation - a non-governmental organisation focused on preserving the islands' wildlife. She believes that money from the EU has been vital in supporting their work. Between 2008-2019, the EU has provided the Falkland Islands with more than £10m - including £1.5m to undertake environmental projects. But this will no longer be available once the UK leaves the EU. One of these projects involves endangered sei whales - one of the world's fastest whales that can reach speeds of up to 30 miles per hour. Michelle's team studied how the whales used the waters around Berkeley Sound - an area in the Falklands. The presence of at least 87 whales there suggested it was an "important feeding area" for them. As a result, future decisions about how best to use these waters, which were previously earmarked for industrial activity like shipping and fishing, as well as tourism, "will take these findings into account", says Michelle
10-24-19 Graffiti on bus shelters saves birds from fatal collisions
Vandalising a bus shelter with graffiti is generally frowned upon, but it turns out that a spray of funky lettering can help save the lives of birds. Shelters made with large panels of clear glass or plastic present birds with an invisible and potentially life-threatening obstacle. Now researchers in Poland have found that the rate of collisions with these structures falls dramatically when they are plastered with opaque graffiti. A team at the Polish Academy of Sciences made regular visits to 81 different bus shelters in the south-west of the country over a year. They looked for signs of impact including ghostly imprints of powder down, a substance that protects a bird’s feathers, left on the shelters’ panels. The researchers found a total of 36 carcasses on the ground at bus shelters. These were always associated with imprint traces, which indicated how slamming into the bus shelters at speed can be fatal. However, the team found that bus shelters covered in graffiti or dust were associated with far fewer signs of impact – and no carcasses. A clean glass shelter was roughly seven times more likely to have evidence of collisions than a clean graffiti-covered shelter. The researchers point out that there are hundreds of thousands of bus shelters in Poland alone. They estimate that up to a million bird collisions may be occurring at these structures every year. The fatal consequences of bus shelters have probably been overlooked, in terms of how dangerous human infrastructure can be for flying fowl, says Erin Bayne at the University of Alberta in Canada. “There’s a lot of bus shelters we’ve probably never counted, putting that into the estimate just is going to push that number much higher,” he says.
10-24-19 Piranhas and their plant-eating relatives, pacus, replace rows of teeth all at once
Not losing teeth individually might help distribute wear and tear from the fishes’ diets more evenly. When it comes to scary teeth, piranhas’ bite is among the most fearsome. Their razor-sharp teeth strip prey’s flesh with the ease of a butcher’s knife. In a process that avoids dulling, the fish lose all their teeth on one side of their mouth at once, with a fresh set growing in five days later. Months later, the same thing happens on the other side of the jaw. That trait was how the carnivorous fish adapted to a diet of scales, fins and flesh, or so scientists thought. Yet it turns out the fierce fish share this toothy trait with their plant-eating cousins, the pacu, suggesting that this tooth replacement strategy evolved earlier in the herbivorous ancestors of piranhas and pacus, scientists report in the September Evolution and Development. That’s perhaps not so surprising, says Matthew Kolmann, a biologist at George Washington University in Washington, D.C. Eating hard seeds and tough stems can damage fish teeth, he says. Cycling through sets of teeth, instead of replacing teeth one at a time, may help the freshwater fish more evenly distribute the wear and tear from chewing. Kolmann and his colleagues took micro CT scans of 93 pacu and piranha museum specimens spanning 40 species. Pacus have a double row of teeth along both the upper and lower jaw, while piranhas sport a single row, like humans. The images revealed well-developed teeth embedded in the jaw parallel to teeth already in use on one side of the mouth. These mature teeth form sawlike blades that lock together as a unit, ready to erupt and replace a lost row. A microscopic look at jaw tissue also showed tiny tooth buds beginning to develop along the opposite jaw.
10-24-19 Earthworms' place on Earth mapped
The first global atlas of earthworms has been compiled, based on surveys at 7,000 sites in 56 countries. The findings will help protect the hundreds of different earthworm species found on all continents except Antarctica. Climate change might have "substantial effects" on earthworms, said an international team of scientists. The burrowing creatures play a vital role in improving the soil but little is known about them on a global scale. We rely on earthworms for increasing crop yields and aerating the soil, but they have been overlooked in the past, said Dr Helen Phillips of the German Centre for Integrative Biodiversity Research in Leipzig. "As children probably the vast majority of us held earthworms in our hands and probably weren't quite aware how significant they are in the environment and for the things that we rely upon," she said. "We should never stop looking at the above ground biodiversity but we really shouldn't be overlooking what's beneath our feet, as well." The international team of 141 researchers from 35 countries mapped global patterns in the number and type of different earthworms and how this is related to factors like soil pH and the climate. They discovered that temperature and rainfall can shape patterns of earthworms in the soil, suggesting climate change might have "serious implications" for both earthworms and the services they provide to nature. Dr Noah Fierer of the University of Colorado, Boulder, who is not connected with the study, said the results underscore that earthworm distributions are highly sensitive to climate, though "it remains unclear how earthworm communities will respond to ongoing climate change". The study, published in Science, found that at a local level, the number of species and the abundance of earthworms is lower in the tropics than in the temperate regions. For example, the soils of southern England are an earthworm paradise, harbouring some of the highest diversity and abundances of earthworms in the world.
10-24-19 Blood transfer from active mice gives lazy ones benefits of exercise
The benefits of exercise can be shared by blood transfer, according to research in mice. Sedentary mice given an injection of plasma from active mice experience more brain cell growth and less inflammation. And a protein that seems to be behind some of the effects could potentially be developed into an “exercise mimetic”. Exercise is good for your body and brain – we know it can reduce inflammation, lower the risk of various diseases and improve our ability to think and learn. Zurine De Miguel at Stanford University in California and her colleagues wondered if exercise might exert these benefits through factors in the blood. To find out, the team compared mice that were able to exercise with a running wheel with a separate group of mice that weren’t able to exercise. After 28 days, the mice that were free to exercise had more new brain cells than the sedentary mice. The team then took blood plasma from the mice that had exercised and injected it into a group of sedentary mice. Another group of sedentary mice were injected with plasma from equally sedentary mice. An injection of “runner plasma” seemed to confer some of the benefits of exercise to the sedentary mice. These mice had significant increases in the number of new brain cells, for example. They also performed better in tests of learning and memory than mice that were given “control plasma” from other sedentary mice. Something in runner plasma appears to change the way genes work. The team found 1974 genes that were affected in the mice depending on which blood plasma they were given. This appears to alter the level of proteins in a way that reduces inflammation in the body and brain.
10-23-19 Gut microbes help mice overcome their fears by changing brain activity
Mice with a disrupted gut microbiota may be unable to shake off fearful memories – a finding that suggests our gut bacteria may play an important role in the way we learn. Over the past decade, there has been increasing interest in the role bacteria play in keeping us healthy, especially those living in our gut, mouth and on our skin. Emerging research has linked disruption of these bacterial communities to problems in the immune system and even changes in behaviour. However, it has been unclear exactly how gut bacteria might bring about behavioural changes. To investigate, David Artis at Weill Cornell Medicine in New York and his colleagues studied the effect antibiotics have on the way mice learn and respond to fearful situations. They trained mice to fear a sound by delivering a small shock to their paws every time they heard it. Afterwards, the mice would freeze in fear when they heard the tone. Over the past decade, there has been increasing interest in the role bacteria play in keeping us healthy, especially those living in our gut, mouth and on our skin. Emerging research has linked disruption of these bacterial communities to problems in the immune system and even changes in behaviour. However, it has been unclear exactly how gut bacteria might bring about behavioural changes. To investigate, David Artis at Weill Cornell Medicine in New York and his colleagues studied the effect antibiotics have on the way mice learn and respond to fearful situations. They trained mice to fear a sound by delivering a small shock to their paws every time they heard it. Afterwards, the mice would freeze in fear when they heard the tone.
10-23-19 Crabs can learn and remember their way through a complex maze
A species of crab can learn to navigate a maze and still remember it up to two weeks later. The discovery demonstrates that crustaceans, which include crabs, lobsters and shrimp, have the cognitive capacity for complex learning, even though they have much smaller brains than other animals, such as bees. “Crustaceans have a brain roughly 10 times less than the size of a bee’s in terms of neuronal count,” says Edward Pope at Swansea University in the UK. Pope and his colleagues trained twelve shore crabs (Carcinus maenas) to complete an underwater maze in an aquarium. The maze had a single correct path to the end, which required five changes of direction and included three dead ends. The researchers placed a single crushed mussel at the end of the maze as a tasty reward. The crabs attempted the maze once a week for four weeks. They did not manage to complete the maze without making a mistake until their third week of training, although they improved after each training session. Pope and his team then waited an additional two weeks before putting the crabs’ memories to the test. This time, the team put the crabs in a maze without an edible reward. All twelve managed to complete the maze within 8 minutes. By contrast, a group of untrained crabs took an average of 39 minutes to complete the maze, with only 7 out of 12 crabs reaching the end in under an hour. “It’s interesting that the crabs can learn the maze,” says Neil Burgess at University College London, UK, though they seem to learn more slowly than rodents or other mammals, he says. Pope says his team next wants to investigate how changing ocean conditions, such as ocean acidification and rising temperatures, might impact the crabs’ ability to learn.
10-23-19 Aye-ayes just got weirder with the discovery of a tiny, sixth ‘finger’
An extra digit, a pseudothumb, may help the primates grip objects. Aye-ayes just got even more unusual. The tiny lemurs of Madagascar, known for their large cartoonish ears and continuously growing incisor teeth, also have a sixth “finger” on each hand. The extra digit — a nubby little “pseudothumb” made of bone and cartilage — can move in three directions and carries its own distinctive fingerprint, researchers report October 21 in the American Journal of Physical Anthropology. “It’s more than just a nub. It actually has a lot of function to it,” says study coauthor Adam Hartstone-Rose, a comparative anatomist at North Carolina State University in Raleigh. The pseudothumb, which is manipulated by three muscles, may help aye-ayes (Daubentonia madagascariensis) grip objects or branches. It’s the first time that a pseudothumb has been discovered on any primate, although some people are born with extra fingers (SN: 6/12/19). Other species also have pseudothumbs, including giant pandas, which use their sixth digits to grasp bamboo stalks (SN: 1/31/19). Giant pandas may have acquired that extra digit after the rest of their fingers became less specialized so that the bears could better walk. That’s not the case with aye-ayes, though, the scientists think. Instead, the little lemurs’ hands may have become too specialized, with thin, elongated fingers, including an especially long third digit that has a ball-and-socket joint. That finger, in particular, is used in a hunting technique called tap foraging, where the animals tap the finger on dead and rotting wood and use echolocation to find bugs hiding inside. Then the primates bite the wood, puncturing a hole, and again use their long third finger for fishing out bugs and grubs found inside.
10-22-19 Scientists have trained rats to drive tiny cars to collect food
Rats have mastered the art of driving a tiny car, suggesting their brains are more flexible than we thought. The finding could be used to understand how learning new skills relieves stress and how neurological and psychiatric conditions affect mental capabilities. We know that rodents can learn to recognise objects, press bars and find their way around mazes. These tests are often used to study how brain conditions affect cognitive function, but they only capture a narrow window of animal cognition, says Kelly Lambert at the University of Richmond. Lambert and her colleagues wondered if rats could learn the more sophisticated task of operating a moving vehicle. They constructed a tiny car out of a clear plastic food container on wheels, with an aluminium floor and three copper bars functioning as a steering wheel. When a rat stood on the aluminium floor and gripped the copper bars with their paws, they completed an electrical circuit that propelled the car forward. Touching the left, centre or right bar steered them in different directions. Six female and 11 male rats were trained to drive the car in rectangular arenas up to 4 square metres in size. This involved rewarding them with Froot Loop cereal pieces when they touched the steering bars and drove the car forward. The rats were encouraged to advance their driving skills by placing the food rewards at increasingly distant points around the arena. “They learned to navigate the car in unique ways and engaged in steering patterns they had never used to eventually arrive at the reward,” says Lambert. Learning to drive seemed to relax the rats. The researchers assessed this by measuring levels of two hormones: cortisol, a marker of stress, and dehydroepiandrosterone, which counteracts stress. The ratio of dehydroepiandrosterone to cortisol in the rats’ faeces increased over the course of their driving training.
10-22-19 White bellbirds have the loudest known mating call of any bird
The males blast a song, which sounds like a melodic air horn, in the face of a nearby female. Make some noise for the white bellbirds of the Brazilian Amazon, now the bird species with the loudest known mating call. The birds (Procnias albus) reach about 125 decibels on average at the loudest point in one of their songs, researchers report October 21 in Current Biology. Calls of the previous record-holder — another Amazonian bird called the screaming piha (Lipaugus vociferans) — maxed out around 116 decibels on average. This difference means that bellbirds can generate a soundwave with triple the pressure of that made by pihas, says Jeff Podos, a behavioral ecologist at the University of Massachusetts Amherst, who did the research along with ornithologist Mario Cohn-Haft, of the National Institute of Amazon Research in Manaus, Brazil. The team measured sound intensity from three pihas and eight bellbirds. Each sounded off at different distances from the scientists. So to make an accurate comparison, the researchers used rangefinder binoculars, with lasers to measure distance, to determine how far away each bird was. Then, they calculated how loud the sound would be a meter from each bird to crown a winner. The small white bellbird, which weighs less than 250 grams, appears to be built for creating loud sounds, with thick abdominal muscles and a beak that opens extra wide. “Having this really wide beak helps their anatomy be like a musical instrument,” Podos says. Being the loudest may come with a cost: White bellbirds can’t hold a note for long because they run out of air in their lungs. Their loudest call sounds like two staccato beats of an air horn while the calls of screaming pihas gradually build to the highest point. Bellbirds don’t use their loudest call to communicate across long distances like other animals do, Podos says. Instead, a male white bellbird blasts its loudest song in the face of a nearby female.
10-22-19 World's 'loudest bird': Meet the white bellbird
You've got to work hard to survive in the wild and for birds, that can mean developing a gimmick. Some birds have evolved with beautiful feathers, others have elaborate courtship rituals - and the white bellbird makes a noise louder than an industrial drill. It's the loudest bird song ever recorded, a study published in Current Biology claims.
10-22-19 A peek inside a turtle embryo wins the Nikon Small World photography contest
The annual competition highlights the power of microscopy to reveal hidden wonders. As scientists scour the natural world in search of truth, they often capture its beauty. Such was the case for microscopy technician Teresa Zgoda and micro-photographer Teresa Kugler. While at the Rochester Institute of Technology in New York, the pair combined fluorescence microscopy and stereomicrography to create a vivid portrait of a developing turtle embryo. Because the embryo was more than 2.5 centimeters long, Zgoda, a recent RIT graduate now at Brigham and Women’s Hospital in Boston, and Kugler couldn’t capture it all in such detail in one image. Instead, they stitched together hundreds of images focused on different locations and layers of the turtle to create a composite of the entire embryo. The pair’s turtle image has won first place in the 2019 Nikon Small World photomicrography competition. “Microscopy lets us zoom in on the smallest organisms and building blocks that comprise our world – giving us a profound appreciation for the small things in life that far too often go unnoticed,” Kugler said in an Oct. 21 news release announcing the results of the annual contest, now in its 45th year.
10-21-19 Giant toad looks and acts like a venomous snake to scare off predators
An African toad has found a nifty way to scare off predators: it looks and sounds like a venomous snake. This strategy of “Batesian mimicry” is common in some other animal groups, but is extremely rare in frogs. “This is the first example in the world – that we are aware of – of a frog attempting to mimic a venomous snake,” says Eli Greenbaum at the University of Texas at El Paso. “It’s rare for frogs to be involved in a mimicry complex in general.” Congolese giant toads (Sclerophrys channingi) are found only in the Democratic Republic of the Congo in central Africa. In autumn 2017, Greenbaum was giving an undergraduate genetics lecture and showed a photograph of a Congolese giant toad. At the end of the class, a student named Theresa Edmondston approached him to say that she kept venomous snakes as pets, and that the photo looked like the head of one of her favourites: a Gaboon viper (Bitis gabonica), which are found throughout sub-Saharan Africa. The snake’s head has a distinctive pattern on its top and back, and the toad’s back appeared to mimic this. Edmondston began researching the two animals, and eventually Greenbaum was intrigued enough to start comparing and measuring specimens. “It became clear slowly over time that, yes, there is some very intriguing similarity here,” he says. The final piece of the puzzle was put in place by Chifundera Kusamba at the Natural Sciences Research Centre in Lwiro, Democratic Republic of the Congo. “He’s got a lot more experience coming across these things in the wild than I have,” says Greenbaum. “He happened to mention, as sort of an offhand comment, that when you come across these things in the wild, they let out a little hiss that sounds like air slowly being released from a balloon.” Greenbaum immediately realised that this could be the toads mimicking the Gaboon viper’s threatening hiss.
10-19-19 Farmed bees are mating with native bees - and that could endanger them
Farmed bees used to pollinate crops in commercial greenhouses are interbreeding with the local bees — and the potential consequences could be dire. Every year, more than one million commercially reared bee colonies are used in greenhouses around the world to help pollinate crops. But these are typically non-native bees, and introducing them to new areas is risky. If they escape, they can compete with local bees for food and nesting resources. They can also spread mites, viruses, and other diseases to native populations, says Sevan Suni at the University of San Francisco. On top of all that, Suni and her colleagues suspected that the farmed bees may also interbreed with local bees and that this could cause further trouble. To investigate, the researchers captured 66 bees in the wild in Andalucía, Spain and analysed their genes. This showed that 63 per cent of the bees had hybridised with the commercial bees. Some of them were found 60 kilometres from the nearest greenhouse. This suggests the native and commercially bred bees are readily interbreeding. The hybridisation can threaten the long-term survival of the native bees, says Ignasi Bartomeus at the Doñana Biological Station in Spain, who also worked the study. “Diversity is the best insurance against [environmental] perturbations because it creates variability from which to adapt to new situations,” he says. “If we homogenise the genetic diversity of some species, we are losing this insurance.” Bartomeus says that the commercial bees hibernate in the winter, while the native bees go into dormancy in the hot Mediterranean summer. “A potential threat is that southern bumblebees may lose their adaptations to warm environments – which is really critical given the climate warming trend we are experiencing,” he says.
10-18-19 The pigs that use tools
Researchers have spotted pigs using tools—a first for this animal, which is known for its intelligence. Many wild animals, such as chimpanzees and dolphins, make use of tools. But until now, neither wild nor domestic swine have ever been seen doing the same. That changed when Meredith Root-Bernstein, an ecologist, observed a wild pig in a Parisian zoo picking up a piece of bark in its mouth and digging in the dirt with it. Root-Bernstein hypothesized that the Visayan warty pig—a critically endangered species from the Philippines—was nest-building, something the animals do every six months to prepare for the arrival of piglets. Colleagues who returned to the zoo the next spring confirmed her theory. Three of the four pigs in the pen were using tools to create a homey nest: a pit filled with leaves. Subsequent visits yielded the same finding. Root-Bernstein says it isn’t yet clear why the pigs use tools, given that their snouts appear better suited for the task. “Learned things and cultural things work that way,” she tells NationalGeographic.com. “Maybe it just feels like the right thing to do.”
10-18-19 Nightmarish northern snakehead
Georgia, which had its first sighting of the nightmarish northern snakehead, an invasive fish that can breathe air and wriggle on land from lake to lake. “Kill it immediately,” Georgia’s Department of Natural Resources advised residents. “DO NOT RELEASE IT.”
10-18-19 New books explore why dogs and humans have such a special bond
Dog Is Love and Our Dogs, Ourselves look at the relationship we have with our canine companions. My 65-pound black mutt is feeling playful. She rams her head into the couch cushions and launches her butt into the air, snuffling and growling excitedly. She achieves a partial headstand and her hind legs kick wildly. She is the embodiment of joy, and that joy is infectious. Dogs have been jubilantly kicking their legs in the air for at least 14,000 years, and during that time they became our devoted companions. Two new books offer different takes on this interspecies bond. The first makes a compelling case that dogs do far more than just obey us — they love us. The other book offers a broader look at all the complexities and contradictions of the human-dog relationship. Clive Wynne, a canine behaviorist and founding director of the Canine Science Collaboratory at Arizona State University in Tempe, has always loved dogs, but it took him many years to become convinced that the feeling is reciprocated. In Dog Is Love, readers accompany Wynne on his scientific journey from skeptic to believer. Not only do dogs love us, he argues, but it is their capacity and desire to connect with humans that makes dogs unique. Many scientists are loath to talk about the emotional lives of animals, love in particular (SN: 3/2/19, p. 28). The concept “seems too soppy and imprecise,” Wynne writes, and we risk anthropomorphizing dogs. But acknowledging their capacity for love is the only way to make sense of why dogs are so devoted to us and thrive in our company, he argues. Dog Is Love takes readers all the way from theories about how dogs became domesticated to recent behavioral, biological and genetics research that provides convincing evidence that our canine companions feel affection. Dogs’ genetic makeup predisposes them to be loving (SN: 8/19/17, p. 8), Wynne argues, and early exposure to humans (or even other animals) solidifies the connection.
10-17-19 Satellites to monitor whale strandings from space
Scientists developing techniques to count great whales from space say the largest ever recorded mass stranding event was probably underestimated. The carcasses of 343 sei whales were spotted on remote beaches in Patagonia, Chile, in 2015 - but this survey work was conducted from planes and boats, and carried out many weeks after the deaths actually occurred. However, an analysis of high-resolution satellite images of the area taken much closer in time to the stranding has now identified many more bodies. It's difficult to give a precise total for the number of whales involved but in one sample picture examined by researchers, the count was nearly double. The new investigation, published in the Plos One journal, was undertaken as a proof of principle exercise by the British Antarctic Survey (BAS) and various Chilean organisations. It's not easy to see an object, even one as large as a great whale, from several hundred kilometres up in space, but the international team believes the capability of modern satellites now makes this a practical task. Being able to detect strandings more effectively will inform the ongoing conservation of whales. It will also flag potentially deteriorating ocean conditions, something the fishing industry for example will be keen to know about. The monitoring of whales from orbit is set therefore to become a powerful tool with which to assess the state of the environment. "The technology is getting better all the time," said Dr Carlos Olavarría from the Centre for Advanced Studies in Arid Zones (CEAZA), La Serena, Chile. "In this study, we were using 50cm resolution images, but the satellites now can see 30cm. In the future, we'd like also to be able to analyse the pictures automatically, rather than manually; and I'm sure as more minds are applied to the problem, this will become possible," he told BBC News.
10-17-19 Why a brainless yellow 'blob' that can learn is mystifying scientists
A yellow organism which looks like fungus but acts like an animal has gone on display at the Paris Zoological Park. The slim mould - Physarum polycephalum - has almost 720 sexes and has been described as one of "nature's mysteries" by scientists. It can heal itself in two minutes if cut in half, and detect and digest food despite not having eyes, a mouth or a stomach.
10-16-19 Why this woman hates to hear about 'big bad wolf'
In Colorado, there is a debate going on about whether wolves should be reintroduced into the wild. As that rumbles on, some are trying to de-stigmatise the creatures through unusual means. If you go for a hike in the Garden of Gods in Colorado Springs, you might just stumble across a canine on a leash leading a pack of humans on a well-trodden trail. It's normally the other way around but with an apex predator like this you soon realise who is in control. These magnificent beasts are often stopped by hikers and others, who with jaws open, ask "Are they real?". And each time, Peggy Jehly, the mother of each of the pack members out stretching their legs on their daily walk, replies: "Yes, they are. But let's be clear - they are high-content wolf dogs." The Californian set up a business eight years ago giving people the opportunity to walk with her animals - all more lupine than canine - in a bid to educate the public about the importance of wolves to the world. Her creatures are also used as wolf ambassadors, going out to schools and events in a bid to help remove the stigma of "the big bad wolf"; a reputation enhanced by villainous portrayals of the beasts in fairy tales such as Little Red Riding Hood and The Three Little Pigs. Jehly says: "I want to dispel the myth that these are bad guys". Jehly doesn't advertise heavily, instead relying often on people stumbling across Colorado Wolf Adventures through word-of-mouth recommendations. She says this is a deliberate strategy as her priority is the welfare of the wolf dogs. The walks are incredibly intimate with groups ranging from solo travellers to just five people heading out each time with the creatures, Jehly and a small troupe of volunteer handlers.
10-16-19 Inside Sri Lanka's deadly struggle to live peacefully with elephants
Sri Lanka has the world's highest rate of human-elephant conflict – last year alone, it killed 70 people and 300 elephants. A simple solution can make all the difference, if people are willing to try it. LIKE many young bull elephants, Brigadier had a strategy. Spending his days in a small patch of forest in north-west Sri Lanka, he would emerge under cover of darkness to feast on crops. One evening, he bundled into an army brigadier’s property, earning him his name and sealing his fate. Government officials captured Brigadier and trucked him to Maduru Oya National Park. But he immediately took off, probably intending to find his way home, got lost and wound up 120 kilometres north at Sampur beach. Incredibly, a navy boat discovered him swimming 5 kilometres offshore and towed him to safety. After his big adventure, Brigadier settled down again, returning to his nocturnal crop-raiding routine. Six months later, he was found dead at the bottom of a well. Apart from the swimming bit, stories like this are common in Sri Lanka, where habitat loss is forcing elephants into an increasingly bloody conflict with humans. When I visited the country to report on efforts to stem the bloodshed, I found that the government’s favoured solution of moving problem elephants into fenced-off national parks isn’t working. Some experts believe it will even backfire, pushing the species to the brink in the country. The only way to secure the future of Sri Lanka’s elephants, they argue, is to find ways to peacefully coexist with them. That is no mean feat. And yet, as I saw for myself in several villages, there is a simple solution. The question is, will it be implemented across the island? And will people accept that the elephants must live among us or not at all? Asian elephants are under pressure. Their numbers have declined by an estimated 50 per cent in the last 75 years, leaving just 40,000 to 50,000 in the wild. Although they aren’t poached anywhere near as much as their African cousins, their forest homes are being rapidly fragmented. Nowhere is the problem more acute than in Sri Lanka. It accounts for just 2 per cent of their total habitat, yet is home to over 5000 Asian elephants – more than 10 per cent of the remaining global population.
10-16-19 Desert ant runs so fast it covers 100 times its body length per second
The world’s fastest ant can run at almost a metre per second, covering more than 100 times its own body length in that time. The Saharan silver ant (Cataglyphis bombycina) has one of the most extreme lifestyles of any insect. It lives in the Sahara desert, where the ground regularly reaches temperatures of 60°C. Most animals find shelter at the hottest times of day, but this is when Saharan silver ants venture outside. In a furious burst of activity that may be as short as 10 minutes, they scavenge for insects and other small animals that have fallen victim to the heat. It has been clear since the 1980s that they run very fast, says Sarah Pfeffer at Ulm University in Germany. Desert ant researcher Rüdiger Wehner reported in 1983 that they might reach 1 metre per second, but this figure has been doubted ever since. “They had no high-speed camera,” says Pfeffer. Pfeffer and her colleagues have now measured how fast Saharan silver ants run using high-speed video. It turns out they can reach 85.5 centimetres per second, which is pretty close to Wehner’s estimate. Close examination of the video revealed several hints about how the ants manage this. First, their legs are unusually short for desert ants – which normally have long legs to keep their bodies away from the hot ground. The short legs allow the Saharan silver ants to take over 40 steps per second. Second, their legs move in an unusual way. Like most insects, the ants move three of their six legs at a time. However, most insects don’t move all three precisely simultaneously. “It’s a very jerky movement if you do that,” says Pfeffer. The Saharan silver ants break this rule, with the legs almost synchronous. “We think this might help them with the sandy substrate,” says Pfeffer, perhaps ensuring that their feet don’t sink into the sand and slow them.
10-16-19 Humpback whales use their flippers to swat salmon into their mouths
Humpback whales use their flippers to create a barrier that traps gathered prey, which they can then usher towards their mouths by swatting the water. Using aerial photography and filming, researchers were able to capture this foraging strategy for the first time. “The first time I saw this behaviour, it was from a boat level view and looked chaotic,” says Madison Kosma at the University of Alaska Fairbanks in the US. “But the whale just kept repeating this behaviour over and over again. I watched it for hours!” Kosma and her colleagues monitored the feeding behaviour of two whales over the course of three years near sites in Southeast Alaska, where salmon are released to boost their population. The researchers photographed and filmed the whales from above during feeding, using digital cameras attached to either a pole or drone. They saw both whales perform the trapping behaviour called “pectoral herding”, which started after the whales had used their flippers to generate a net of bubbles to confine prey near the water’s surface. Both whales then performed the technique, using their flippers to create a physical barrier that prevented prey from escaping. This was followed by a rapid lunge towards the prey, which were engulfed into the whales’ open mouths. One of the whales was also seen using its flippers to guide prey towards its mouth. Over 90 per cent of the pectoral herding was used for targeting juvenile salmon. The whales performed pectoral herding both when they were moving vertically and horizontally. Humpback whales have long flippers, called pectorals, which increase their manoeuvrability by helping them navigate in shallow water and accelerate rapidly. This is the first direct evidence that humpback whales use their flippers to herd prey, says Patrick Miller at the University of St Andrews in the UK, who was not involved in the study.
10-16-19 Humpback whales use their flippers and bubble ‘nets’ to catch fish
New details show how the animals use their long flippers and a whirl of bubbles to hunt. Humpback whales need to eat a lot every day, and some even use their flippers to help snag a big mouthful of fish. Researchers filmed humpbacks (Megaptera novaeangliae) hunting with this tactic, called pectoral herding, off the Alaskan coast. It’s the first time that this behavior has been documented in such detail, the team reports October 16 in Royal Society Open Science. Humpbacks often feed by lunging with their mouths open to catch any fish in their path. Sometimes, the whales will swim in an upward spiral and blow bubbles underwater, creating a circular “net” of bubbles that makes it harder for fish to escape (SN: 10/20/15). “But there’s so much you can’t see while you’re looking at these animals, standing on a boat,” says Madison Kosma, a whale biologist at the University of Alaska Fairbanks. The researchers got a better view of the whales feeding at the ocean’s surface by flying a drone over the water or extending a video camera attached to a pole from the walkways of floating salmon hatcheries. Over the three-year study from 2016 to 2018, the team noticed that two whales repeatedly consolidated fish inside bubble nets using their two long, pectoral flippers. In horizontal pectoral herding, whales blew a bubble net before splashing a flipper at weak parts of the net to reinforce the barrier. In vertical pectoral herding, whales created a bubble net and then raised their flippers — like a referee signaling a touchdown — as they ascended up through the net from deeper water, helping guide fish into their mouths. What’s more, the whales sometimes tilted one or both of their flippers, reflecting sunlight off the white skin on the underside to disorient fish, the researchers say.
10-16-19 Southwest Atlantic humpback whales on recovery path
One of the whale populations taken to the edge of extinction by commercial hunting in the early 20th Century has essentially recovered its numbers. It's estimated the humpbacks that frequent the southwest Atlantic once totalled perhaps 27,000 animals. This group was reduced to only a few hundred by the steam-driven boats and harpoons operating out of the British Overseas Territory of South Georgia. But a new study suggests the humpbacks are back close to where they were. It's reckoned there are now just short of 25,000 individuals in the southwest Atlantic - more than 90% of the pre-exploitation level. "It's a positive story," said Dr Alex Zerbini, the report's lead author from the National Marine Fisheries Service, part of the US National Oceanic and Atmospheric Administration (Noaa). There are seven Southern Hemisphere populations of humpbacks (Megaptera novaeangliae), each of which can be described by their distinct genetics and migratory behaviour. This particular group has a winter breeding ground off the coast of Brazil, and travels to sub-Antarctic and Antarctic waters in summer to gorge on the regions' swarms of krill crustaceans. It's this southern feeding excursion that brought the marine mammals into contact with the industrial fishery based on South Georgia from 1904. Humpbacks were really the first whale species to be targeted in the nearshore waters around the island and their numbers quickly plummeted to unsustainable levels. Indeed, the animals had become so rare by the late 1920s that whaling ships could only find and catch a few dozen individuals per year. "South Georgia's whaling stations were able to continue by switching to other species, going after blues, fins, and then sei whales. It was a sequential collapse," Dr Zerbini told BBC News. "Finally, they went after minke whales, the smallest of the great whales, before the moratorium was introduced in the 1980s."
10-15-19 Nightjars time their epic migration flights using a lunar calendar
The European nightjar, which migrates from northern Europe to sub-Saharan Africa, seems to synchronise its flying with phases of the moon. It is the first time an animal’s migration patterns have been shown to be associated with the lunar cycle. “Most birds migrate at night, therefore the effect of moonlight on migration has always been an open question,” says Cecilia Nilsson at Cornell University in New York. Until now, there was little evidence of a connection, though nightjars were a natural choice to look for one. The birds feed at night, snatching insects from the air. We already knew that they change their feeding habits based on the moon’s phase, gobbling more insects on bright, moonlit nights. Could nightjars also be scheduling their migration in a similar way? To find out, Gabriel Norevik at Lund University in Sweden attached tracking devices to 39 European nightjars. Some of these devices measured the birds’ position using GPS, while others tracked their acceleration. This allowed Norevik and his team to record location over the year and flight activity levels night after night. Their results reveal a key role of the full moon in the nightjar’s itinerary, which consists of long night-time flights with daytime resting punctuated by much longer rests at stopover sites. On moonlit nights, the birds’ foraging during migration stopovers more than doubled. Then, as the moon wanes, increasing numbers of nightjars embark on flights along their migration route, peaking at around 11 days after a full moon. Sometimes, all of the tracked birds would migrate simultaneously at this time in a great pulse. The team also found that the birds concentrate their feeding activity at dawn and dusk on most nights, only foraging through the night when there is plenty of moonlight.
10-13-19 Thai elephant deaths: Do elephants risk their lives to save each other?
Last week, Thailand suffered one of its biggest ever single elephant tragedies, when 11 animals in one family died in a swollen river. At first only six elephants were thought to have died - days later another five were spotted downstream. The initial theory from park rangers in Khao Yai National Park was that they died in a rescue mission. As they crossed the treacherous 150m-tall Haew Narok - or Hell's Falls - a baby slipped and the others fell trying to save it. Though the loss of 11 elephants isn't catastrophic to the species, there is something about them that draws us in, and this apparent self-sacrifice struck a chord around the world - millions of you read our story alone. But emotions aside, how plausible is it that elephants would have both the empathy and skill to risk their lives for a baby? And perhaps more importantly now, what does this mean for the survivors? Dr Joshua Plotnik, assistant professor of psychology at Hunter College City University of New York, has been studying elephants in Thailand for more than a decade. He told the BBC that with no witnesses, we can't assume what happened. But he says it's "certainly reasonable to suspect that when an elephant in a family group is in danger the other elephants might do everything they can to go help". There is well documented evidence of elephants recognising danger and co-ordinating their actions to stage a rescue. But Dr Plotnik says it seems unlikely that they would "actively all go over a waterfall in a dangerous situation like that". It was more likely a terrible accident. Dr Rachel Dale, an elephant behaviour specialist at the University of Veterinary Medicine in Vienna, agrees that elephants will unquestionably help an elephant in danger, "even if it's at a cost to themselves". But they're also "smart animals, really smart", she says, so probably have the ability to carry out a kind of perfunctory risk assessment before rushing in.
10-11-19 The spotted lanternfly
Southeastern Pennsylvania residents have declared war on an invasive insect species that has overrun their region. “Stomp them. Squish them. Destroy them,” reads one poster, in reference to the dreaded spotted lanternfly. The plant-hopping bug, which is native to southeastern Asia, appeared locally five years ago, and its exploding population is damaging valuable trees and grapevines, dropping sticky waste on decks and pools, and landing on people in writhing swarms. “We’re outnumbered,” said Phoenixville resident Lori Beatrice. “It’s just gross. It’s like waking up in a nightmare.”
10-10-19 You probably score worse than monkeys on questions about the world
New Scientist readers are more knowledgeable than the general public and experts on some issues, but still score worse than monkeys on some questions. “To score worse than monkeys requires misconceptions,” Ola Rosling, author of Factfulness, told New Scientist Live on Thursday. Most people are not only ignorant about some basic facts about the world, they don’t even realise that they are ignorant, he said. For example, globally around 88 per cent of children are now vaccinated against at least one disease, but most people think the figure is much lower. Given a choice between 20, 50 or 80 per cent, only around 15 per cent of people in countries such as the US and UK get the answer right in Rosling’s surveys. At a recent world health summit, only 27 per cent of attendees got it right. Nobel laureates and medical scientists would be outsmarted by monkeys randomly picking answers, he said. “Is IQ correlated with factual knowledge? Not in the fields we have tested so far,” said Rosling. In an online survey, 46 per cent of New Scientist readers got the answer right to the vaccination question – better than the experts. “In any other test, it would be seen as a huge failure,” he said.On climate, New Scientist readers excelled. Asked what climate experts believe will happen to global temperatures over the next 100 years – warmer, same or cooler – 99 per cent opted for the right answer. In other surveys, the proportion getting this right ranges from 94 per cent in Hungary to just 76 per cent in Japan. In the US, 81 per cent get in right, and in the UK 87 per cent. New Scientist readers also did relatively well when asked if the proportion of the world’s population living in extreme poverty has halved, remained the same or doubled. In most countries, less than 10 per cent of people pick the right answer (it has halved). But 53 per cent of New Scientist readers got it right. Among the audience at the New Scientist Live talk, 81 per cent got it right.
10-10-19 Bees are better at counting if they are penalised for their mistakes
Honeybees may be better at counting when they are punished for making mistakes compared to when they are simply rewarded for correct answers. We already had some evidence suggesting bees can count up to four. But it turns out they may be capable of grasping larger numbers too. Scarlett Howard at the University of Toulouse in France says she thought we might be underestimating the numerical abilities of bees, which prompted her colleagues to investigate further. The team first trained bees to enter a chamber from where they could see two channels with images at their ends. One channel always had an image showing four shapes, while the other had an image bearing between one and 10 shapes.The bees were then split into two groups. The first were trained to pick the image with four shapes, getting a reward of sweet sucrose solution for choosing that and bitter tasting quinine solution for choosing the other image. The second group were rewarded with sucrose solution for picking the four-shape image, but not penalised for choosing the other. The team then separately tested whether the bees could identify images showing four shapes compared to images showing five, six, seven or eight shapes. They were again put in a chamber from where they could see the images at the ends of two separate channels and the researchers counted how many times the bees chose the image with four shapes.They found that only the bees that had been conditioned with both rewards and penalties could choose the image with four shapes at a level higher than chance. When choosing between images showing four and five shapes, the bees went for four 59 per cent of time, suggesting they can understand numbers beyond four. Lars Chittka at Queen Mary University of London compares the findings to the stick and carrot method. He says when there is a punishment for getting an answer incorrect, the motivation to be correct is heightened.
10-10-19 Natural 'bumblebee medicine' found in heather
Preserving heather in the natural landscape could have benefits for wild bees, according to new research. Nectar - and therefore honey - from the plant contains a natural "bumblebee medicine", which is active against a harmful bee parasite. Heather is a major foraging plant for wild bees, which are under pressure from habitat loss, disease and pesticides. Lime trees and the strawberry tree also contained the "medicine" but at lower levels. Heather is a natural part of heathland and moorland, where it is an important source of nectar for wild bees and other pollinators. The purple blaze of heather is becoming a less common sight, as heathlands and moorlands are lost. Lowland heathland, with its gorse, grasses and heather, is being given up to farming or conifer plantations, while upland moorland is at risk from grazing and burning. The scientists say continued loss and degradation of heathlands due to human actions may lead to the loss of a major medicinal plant for pollinators. "Our work shows that heathlands may be even more valuable than previously thought by providing wild bumblebees with a natural medicinal nectar as protection against a major parasite," said co-researcher Dr Hauke Koch of the Royal Botanic Gardens, Kew.The researchers from Kew and Royal Holloway, University of London, investigated plants for medicinal properties that could protect pollinators in the wild. They tested nectar from 17 plants, including ivy, heather, clover and dandelion, for medicinal effects on a parasite found in the gut of bumblebees. Nectar from heather (Calluna vulgaris) had the most potent effect, due to a single chemical known as callunene. The strawberry tree (Arbutus unendo) and lime trees also had some medicinal activity. "Understanding which plants are needed to maintain a healthy balance between bees and their parasites can help us restore habitats that maximise bee health," said Prof Mark Brown from Royal Holloway.
10-10-19 Deep-sea anglerfish may shed luminous bacteria into the ocean water
Something strange is going on in the deep sea. Luminous bacteria have teamed up with predatory anglerfish, which may use the glowing microbes to help catch prey. The bacteria have evolved to depend on the anglerfish – yet they spend much of their time floating free in the water. Anglerfish are predatory fish with large teeth. On their forehead they have a long, thin growth called an esca, which resembles a fishing line. The tip of the esca is often luminous. Many anglerfish live in the pitch-black deep sea and may use the glow to lure in prey. Little is known about them, says Tory Hendry of Cornell University in New York. For instance, there is no evidence that the esca is a lure, “other than it looks like a lure”, she says. However, we do know that many anglerfish have bacteria living in their escas, which supply the light. Hendry’s team has previously found that these bacteria have lost about 50 per cent of their DNA, and with it many abilities. “They rely on glucose from the host,” she says. This discovery implied that the bacteria spend all their lives inside anglerfish. In line with this, the team found that two anglerfish species each had their own species of bacteria. Hendry’s team has now overturned this. The researchers sequenced the DNA of the bacteria found in the escas of seven anglerfish species, belonging to six genera. One species of anglerfish had its own unique bacteria, but the others all shared the same species of bacteria. The only explanation is that the bacteria live in the water and the anglerfish collect them, says Hendry. This implies the bacteria are widespread, as anglerfish from both the North Atlantic and Gulf of Mexico had the same species. “There has to be an environmental pool that all these fish are getting their symbionts from,” says Hendry.
10-10-19 How tardigrades protect their DNA to defy death
A ‘fluffy cloud’ of protein shields water bears’ DNA from radiation, drying and other damage. Tardigrades may partly owe their ability to survive outer space to having the molecular equivalent of cotton candy. Water bears, as the creatures are also known, can famously survive just about anything (SN: 7/14/17), including being bombarded with X-rays or cosmic rays, or being doused in hydrogen peroxide. Such radiation and chemical exposure result in production of DNA-damaging hydroxyl radicals, molecules composed of oxygen and hydrogen. Previous research indicated that a protein called Dsup, for damage suppressor, shields the tardigrade species Ramazzottius varieornatus from radiation. When added to human cells, the protein also protects against radiation. Now researchers have found out how. Dsup surrounds nucleosomes — DNA wound around proteins called histones — “like a fluffy cloud of cotton candy,” molecular biologist James Kadonaga of the University of California, San Diego in La Jolla and colleagues report October 1 in eLife. That cloud keeps hydroxyl radicals away from DNA. Another tardigrade species Hypsibius exemplaris, previously thought to lack Dsup, has its own version of the protective protein, the researchers discovered. Only about 26 percent of the amino acids in the two species’ Dsup proteins are alike, but both shroud DNA against damage. Kadonaga says the proteins probably evolved to protect tardigrades from hydroxy radicals when the moss-dwellers are dried out, a frequent occurrence (SN: 12/16/15). Drying increases the concentration of DNA-dinging radicals in cells. And damage can’t be repaired while the animals are dormant in their desiccated state. Since X-rays also form hydroxy radicals, tardigrades “just happen to be X-ray resistant,” too, he says.
10-9-19 Are experiments on how animals think ever justified?
As research reveals ever more similarities between the human experience and that of many animals, it becomes harder to defend the pursuit of such knowledge AS A primate with sophisticated cognitive abilities, you may remember a recent story we ran about experiments on macaques. It showed that these monkeys can understand the logical process of transitive inference. In other words, if a macaque learns that A comes before B, and B comes before C, it can then deduce that A must come before C. To get the animals to take part in the tests, they were put on what the paper in Science Advances called a “fluid-restricted” diet. Water became a reward for doing the puzzles. The study’s findings are interesting – but are they interesting enough to justify the method? The debate about the merits of experiments on animals usually centres on those done for medical purposes. Many people are willing to accept drug testing on rodents or studies involving primates if such efforts are in pursuit of new treatments for our most unpleasant diseases. Last year, a poll suggested that two-thirds of people in the UK accept animal experiments being carried out for the purposes of medical or scientific research provided there is no alternative. But when investigating questions such as “do monkeys have logic” or “can we implant memories in birds’ brains” (see “implanting false memories in a bird’s brain changes its tune”) there clearly is an alternative – not asking them at all. As our Insight explores, there are still various reasons to carry out this sort of work. One is that it may help us look after animals in our care better, including those in laboratories. Experiments have shown, for example, that rats don’t want bigger cages, they want ones with places to hide.
10-9-19 Climate change: Emperor penguin 'needs greater protection'
Antarctica's Emperor penguins could be in real difficulty come 2100 if the climate warms as expected. Experts say the birds raise their young on sea-ice and if this platform is greatly curtailed, as the models project, then it's likely to put the animals' numbers into steep decline. One forecast is for the population to be halved by the end of the century. Researchers are calling for the conservation status of Emperors to be upgraded. At the moment, they are classified as "Near Threatened" by the International Union for Conservation of Nature (IUCN), the organisation that keeps the lists of Earth's endangered animals. A proposal will be submitted shortly to lift Emperors into the more urgent "Vulnerable" category. "These are very resilient birds; they experience really tough winters and keep coming back year after year to their breeding sites to raise their chicks," explained Dr Michelle LaRue, who's co-authored a new report on the penguins' situation in the journal Biological Conservation. "Emperors are fighters, but our concern is how long their resilience will continue into the future," the University of Canterbury, New Zealand, researcher told BBC News. The penguins' breeding success is critically dependent upon so-called "fast ice". This is the sea-ice that sticks to the edge of the continent or to icebergs. It's low and flat, and an ideal surface on which to lay an egg, incubate it and then raise the subsequent chick in its first year of life. But this seasonal ice needs to be long-lived, to stay intact for at least eight or nine months. If it forms too late or breaks up too early, the young birds will be forced into the sea before they're ready, before they've lost their down and grown water-proof feathers. Likewise the adults. They undergo a dramatic moult in the summer months of January and February. They too risk drowning if the fast ice melts away and they don't have the right plumage to resume swimming.
10-9-19 Experiments show us how animal minds work – but should we do them?
We've now found that budgies have empathy and macaques use logic. But such experiments mean keeping animals in unnatural conditions, raising questions about their value. AYUMU the chimpanzee sits behind a glass wall taking a memory test. He sees a sequence of numbers randomly set out on a touchscreen, memorises them and, when they disappear, taps out a pattern to indicate where they were. For a correct answer, he is given a small reward of food. The ape featured in a 2012 documentary, Super Smart Animals, and the research he was involved in at Kyoto University in Japan revealed that young chimpanzees have a better working memory for numbers than human adults. The experiment with Ayumu is just one example of research that is confirming how sophisticated animal minds can be. The trouble is, many studies like these involve housing animals in laboratory conditions or incentivising them to do a test by restricting their food or water. In recent months, New Scientist has reported on findings that chimps bond after watching films together macaque monkeys can use logical reasoning to solve puzzles and that implanting memories in the brains of zebra finches can alter their songs (see page 17). All these studies involved manipulating animals in unnatural ways. There has long been a debate about the merits of animal experiments, especially in medical research. But when animal behaviour or cognition experiments are unlikely to lead to medical advances, the purpose of such studies can seem less immediately clear. In the US, the total number of animal studies under way is difficult to come by because there is no requirement to record experiments involving mice, rats and fish. However, the US Department of Agriculture does report the use of cats, dogs, farm animals, non-human primates and a few other species. In 2017, its records show that more than 250,000 animals were used in research that involved pain and being given pain-relieving drugs. Some 30,000 of these were non-human primates. (Webmaster's comment: These creatures are all living sentient beings. We have no right to force them to live in our experimental conditions.)
10-8-19 Genome-edited bull passes hornless gene to calves
Researchers have used genome editing to generate hornless cattle, which then pass on the trait to their offspring. The absence of the horns means they cannot use them to injure other animals - or, indeed, humans. Dehorning - along with "disbudding", which removes the horn buds at an early age - is an unpleasant process with implications for animal welfare. Hornless cattle are easier to transport and need less space at a feeding trough. The scientists from the University of California, Davis, along with one colleague from the University of Mansoura, Egypt, have published their findings in the journal Nature Biotechnology. "We've demonstrated that healthy hornless calves with only the intended edit can be produced, and we provided data to help inform the process for evaluating genome-edited animals," said co-author Alison Van Eenennaam, from the UC Davis department of animal science. Dr Van Eenennaam said genome-editing offered a pain-free genetic alternative to removing the horns physically. In 2016, scientists reported that two male dairy bulls had been born with a hornless mutation that had been introduced into their DNA sequence using genome editing. The mutation is dominant, which - in this case - means that all the calves end up with the hornless trait. The latest work was carried out to determine whether the genome edit had been faithfully passed on to one of the bulls' offspring - and to look for any unexpected changes. The researchers sequenced the genomes (the full complements of DNA stored in the nuclei of animal cells) of the calves and their parents for analysis. This showed unequivocally that the genome-edited traits had been passed on to the calves.
10-8-19 Burrowing birds create pockets of rich plant life in a desert landscape
Mounds of sand dug out by nest-digging birds are microhabitats where seeds can germinate. In the rain-starved deserts of coastal Peru, tiny patches surprisingly rich in plant life dot the landscape. Burrowing birds may be responsible, scientists say. Mounds of sand shoveled out by nest-digging burrowing owls and miner birds harbor more seedlings and exclusive plant varieties compared with surrounding undisturbed soils, researchers from the National University of San Marcos in Lima, Peru report in the October Journal of Arid Environments. Although the mounds hold fewer seeds, the structures may provide a sheltered and moist germination environment at the start of the growing season — unlike adjacent crusty soils carpeted with cyanobacteria, lichen, moss and algae. “The ability of seeds to germinate in the desert is a daunting task,” says Jayne Belnap, a U.S. Geological Survey ecologist based in Moab, Utah, who wasn’t involved in the study, “especially if you have a crust.” That crust inhibits seed growth in two ways. Seeds stranded on top are exposed to the harsh environment, and may not be able to sprout at all. And the crust itself can act as a barrier for water to reach buried seeds, and for seedlings to emerge. But when burrowing birds break the crust and dig up sand, seeds can mix into the sand, and water may pool between the tossed sand and crust, the researchers say. That allows seeds to become buried and accumulate moisture needed to germinate. While it’s known that burrowing mammals can break compacted soils and create nutrient-rich hot spots ideal for plant establishment, this study is the first to document similar ecosystem engineering done by dryland birds.
10-5-19 Six elephants die trying to save each other at Thai waterfall
Six elephants have fallen to their deaths in Thailand while trying to save each other from a notorious waterfall. Officials said the incident occurred after a baby elephant slipped over the waterfall in southern Thailand's Khao Yai National Park. Two other elephants have been spotted on a cliff edge nearby, and Thai authorities are trying to move them. There have been similar incidents previously at the same waterfall, known locally as Haew Narok (Hell's Fall). A herd of eight elephants died after falling in 1992. Thailand's Department of National Parks, Wildlife and Plant Conservation (DNP) said officials were called to the scene on Saturday at 03:00 local time (20:00 GMT on Friday) when a group of elephants was blocking a road by the waterfall. Three hours later, the body of a three-year-old elephant was spotted near the base of Haew Narok, and five others were discovered nearby. Edwin Wiek, the founder of Wildlife Friends Foundation Thailand, said any elephants left in the herd would have difficulty surviving as the animals rely on each other for protection and finding food. The incident could also take an emotional toll. Elephants have been known to display signs of grief. "It's like losing half your family," Mr Wiek told the BBC. (Webmaster's comment: All the good traits of human beings are expressed in this incident. Animals have the same drive to help others of their kind as humans do.)
10-4-19 Cats do love their humans
Good news for cat owners: Your pet really does care about you. Cats have long been stigmatized as Machiavellian loners who regard their owners as little more than a useful source of food. But researchers at Oregon State University have found that cats can bond with us just as strongly as dogs or infants do. To analyze the human-feline relationship, scientists recruited 117 cats and their owners to take part in a “strange situation” test. To start, a cat and its owner entered an unfamiliar room together. After two minutes, the owner walked out. When the owner returned, two minutes later, scientists observed the cat’s response. Some two-thirds of the kitties went to greet their owners, then went back to exploring the room. Those animals were securely attached to their owners, researchers concluded, using them as a safe base in an unfamiliar situation. One-third of the felines showed insecure attachment, shunning their owners or clinging to them when they returned. Studies of dogs and children have yielded similar results, with 65 percent of infants and 58 percent of dogs showing a secure attachment to caregivers. “The more we find out about cats,” lead author Kristyn Vitale tells The New York Times, “the more we’re seeing that they are social creatures.”
10-4-19 Honey fungus secrets fall to science
Citizen scientists have helped shed light on a "humungous fungus" that can kill off common plants. The honey fungus often appears at the start of autumn, when honey-coloured toadstools appear on woody plants. Plant pathologists compared more than 5,000 records of confirmed cases with a previous study into susceptibility by the University of California. They found plants in UK gardens fall into three categories, based on their risk of the disease. Plants in the Myrtales order of flowering plants - including myrtle and fuchsia - and Ericales - including camellia and heather - tended to have low susceptibility, while those in the Saxifragales - such as liquidambar and witch hazels - and Fagales - birch and sweet chestnut - were mostly highly susceptible. A third group of plants were in the middle, including maple, magnolia and rose. Senior plant pathologist at the Royal Horticultural Society (RHS), Matthew Comey, said a database compiled from a large number of confirmed samples supplied by gardeners was behind the findings. "The RHS has long advised on what plants might be best avoided if honey fungus is a known problem on your plot but this new research, for the first time, also accounts for a plant's popularity in gardens and therefore the diseases' likely true impact," he said. "Following the planting advice isn't a guarantee against the disease but a sensible precautionary measure akin to practicing good plant hygiene." Honey fungus has been made worse in recent years by warm, dry summers, which make plants more susceptible to attack. The fungus colonises and kills a variety of trees and woody plants and once present in a garden can be managed but not eradicated. The yellow-brown mushrooms that appear above ground are the fruiting bodies of much larger organisms, which can spread large distances underground. A specific honey fungus measuring 2.4 miles (3.8 km) across in the Blue Mountains in Oregon is claimed to be the largest living organism on Earth.
10-4-19 Home aquarium hobbyists are helping save 30 rare fish from extinction
Keeping fish as a hobby can harm wildlife – but it can also help save endangered species. Dedicated aquarium enthusiasts are keeping alive 30 fish species now believed to be extinct in the wild and helping preserve hundreds more species. “Many species already extinct in the wild only exist because they are being kept and bred by these hobbyists,” says Jose Valdez at Aarhus University in Denmark. The pet trade is often part of the problem. For instance, clownfish vanished from some reefs after they became wildly popular as pets after the 2003 movie Finding Nemo was released. Marine fish are still sometimes caught alive using cyanide, which damages coral reefs. And many harmful invasive species are releases or escapees from aquariums. “There are cases in which the pet trade has been harmful,” says Kapil Mandrekar at the State University of New York. But many fish are now bred in captivity or caught on a sustainable basis with the help of local communities, he says. The CARES (Conservation, Awareness, Recognition, Encouragement, and Support) Fish Preservation Program, founded by enthusiast Claudia Dickinson in 2004, is doing much more. It is encouraging fish-keepers to keep, breed and exchange endangered fish to help preserve viable populations. CARES has compiled its own priority list of nearly 600 freshwater fish, which has now been assessed and compared with official lists of endangered species by Valdez and Mandrekar. The pair found 80 of the species on the CARES list have yet to be formally described by scientists. The list of species CARES says is extinct in the wild also includes 30 additional species to those on the Red List of threatened species maintained by the International Union for Conservation of Nature. Members of the preservation programme are keeping populations of these alive.
10-4-19 Evacuating Australia's drought-affected fish
In early 2019, up to a million fish died in Australia's Darling River after drought and extreme weather. Authorities are now painstakingly trying to relocate as many fish as they can, as another summer approaches.
10-3-19 More than a quarter of UK mammals face extinction
More than a quarter of mammals are facing extinction, according to a detailed and devastating report on the state of the natural world in the UK. It also said one in seven species were threatened with extinction, and 41% of species studied have experienced decline since 1970. Providing the clearest picture to date, the State of Nature report examined data from almost 7,000 species. It drew on expertise from more than 70 different organisations. These included wildlife organisations and government agencies. The report said 26% of mammal species were at risk of disappearing altogether. A separate report outlined the picture in Scotland, where the abundance and distribution of species has also declined. Scotland saw a 24% decline in average species abundance, and about one in 10 species threatened with extinction. A quarter of moths have been lost, and nearly one in five butterflies. Their numbers continue to plunge. The State of Nature report shows, in grim detail, that almost one in five plants are classified as being at risk of extinction, along with 15% of fungi and lichens, 40% of vertebrates and 12% of invertebrates. It paints a picture of what conservationists call "the great thinning", with 60% of "priority species" having declined since 1970. There has been a 13% decline in the average abundance of species studied. Our wildlife is also changing more and more quickly. Researchers found more than half of species had either rapidly decreased or increased in number over the last 10 years. Daniel Hayhow from the RSPB, lead author of the report, said: "We know more about the UK's wildlife than any other country on the planet, and what it is telling us should make us sit up and listen. We need to respond more urgently across the board."
10-3-19 Humans may be trading far more species of wildlife than we thought
More than 5000 species of wildlife are being bought and sold legally and illegally around the world, according to new estimates. That figure may be far higher than previously thought. Previous assessments of this trade have looked at data from either the International Union for Conservation of Nature Red List or the Convention on International Trade in Endangered Species of Wild Fauna and Flora. For the new estimate, David Edwards at the University of Sheffield, UK, and his colleagues combined information from both sources and overlaid it with maps of where the species are found. They found 5579 species of vertebrates – nearly a fifth of the total vertebrates examined – are traded. This is 40 to 60 per cent higher than previous estimates. But certain groups are targeted more than others. It turns out that 27 per cent of known mammal species are traded, for example. South America, South-East Asia and central and south-east Africa emerged as the epicentres of the industry. The exercise revealed that people tend to trade species with larger body sizes and some form of evolutionary distinctiveness. That insight was in turn used to build a model for predicting which species may be traded in the future. This suggested that between 303 and 3152 more species are at risk. Edwards says the team’s aim wasn’t just to provide a list of threatened species but “to allow a kind of proactive switch, to start thinking about species that are already potentially at risk of being drawn into trade – a kind of watch list”. Such information should help target resources for monitoring legal trade and stopping illegal trade, he says.
10-3-19 Global wildlife trade higher than was thought
At least one in five vertebrate species on Earth are bought and sold on the wildlife market, according to a study. Scientists say they are "astounded" by the figures, which are about 50% higher than previous estimates. The wildlife trade is the number one cause of animal extinction, tied only with land development. Trade in the likes of horns, ivory or exotic pets is already a multi-billion-dollar industry and looks set to grow. "The sheer diversity of species being traded is astounding - the risk that that will grow is very worrying," said Prof David Edwards of the University of Sheffield, a co-researcher on the study. The study, published in Science, identified hotspots for traded birds, mammals, amphibians and reptiles in regions within the Andes and Amazon, sub-saharan Africa, South East Asia and Australia. The research also identified another 3,000 or so species that look set to be traded in the future, based on their similarities with animals currently bought and sold, for example bright plumage or exotic horns. This would see as many as one in three land-based animal species being traded for products such as meat, medicines or trophies. "If one species is traded, the chances are its evolutionary cousins are also traded," said Dr Brett Scheffers of the University of Florida. "Once we discovered that pattern, we could develop a new model that would predict which species are likely to be traded in the future, even if they are not traded now." The scientists stress the need for proactive rather than reactive strategies designed to combat global wildlife trade, including a "watch list" of susceptible species, better detection of illegal imports, fighting corruption and engaging local people in conservation. "Without urgent focus on how to stem both the supply and demand for wild-caught species, there is a real danger that we will lose many traded species," said Prof Edwards.
10-3-19 Thousands of UK wildlife and plant species are in decline.
The UK’s ongoing loss of wildlife and plants is showing no signs of slowing. The most comprehensive assessment yet of the state of nature in the UK has found that the area occupied by more than 6500 species has shrunk by 5 per cent since 1970. Of the species that we have more detailed data on, nearly 700 saw their numbers fall by 13 per cent. The declines have left 15 per cent of species facing extinction, including the turtle dove, numbers of which are down 98 per cent in half a century. “We have this pattern of ongoing loss, which is showing no slowing in the rate of decline. Overall, we are losing more species than we are gaining,” says Daniel Hayhow of the Royal Society for the Protection of Birds. The RSPB is a member of the State of Nature partnership alongside other conservation groups, such as The Wildlife Trusts, and government bodies such as Natural England. While the 5 per cent fall in distribution of species may sound small, Hayhow calls it a “canary in the coal mine signal” because changes in distribution usually happen much more slowly than changes in abundance. This year’s report was able for the first time to draw on figures on less well-studied species, such as lacewings, hoverflies and lichens, after biases in the data were adjusted for. The picture for moths and butterflies, such as the northern brown argus, is one of steep declines. Mammals and birds show a slight increase since 1970, which masks dramatic falls in some species such as kittiwakes and hen harriers. “You’ve got some species declining at a rate that is a massive conservation concern,” says Hayhow. The biggest driver for change is the intensification of farming, followed by climate change. Public funding for nature conservation has also been hit hard, falling by 42 per cent as a percentage of GDP between 2008 and 2018. Cuts mean public spending on biodiversity is now at £456 million a year.
10-3-19 Implanting false memories in a bird's brain changes its tune
Young zebra finches have had memories implanted in their brains that change the length of the notes they sing. The process involved manipulating a region of the brain that birds use to learn their song. The zebra finch song consists of a series of short notes, or syllables. Zebra finches normally learn their song by memorising the song of their father, then slowly learning to copy it. Todd Roberts at the University of Texas Southwestern Medical Center and his colleagues are working on understanding how memories are encoded in the brain – particularly memories that guide the development of speech and social skills. Previous work had shown that a region of the brain in birds called HVC is important for learning songs, and disrupting its activity interferes with the ability to learn songs. This area receives input from another area called NIf, and neurons in this structure fire at the beginning and end of syllables. That suggested these neurons have a role in coding the length of syllables. To investigate further, Roberts’s team used a technique called optogenetics to manipulate neural activity at the connections, or synapses, between NIf and HVC neurons. This involves inserting genes into neurons that allow them to be controlled by light, then using small fibreoptic cables to shine light onto the selected brain area. Roberts’s team performed the experiments on young male zebra finches that had never been exposed to singing adults but were starting to develop their own song. The group then analysed differences in the final tune about 30 days later. When the team used short pulses of light, the birds produced songs with short syllables. With long pulses of light, the birds produced songs with long syllables. “We identified a pathway in the brain that if we activate, it can implant false memories for the duration of the syllables, without the bird having experience with another bird,” says Roberts.
10-3-19 Gene editing can make fruit flies into ‘monarch flies’
Only three molecular changes are needed for fruit flies to digest milkweed toxins. Gene-edited fruit flies have gained some of monarch butterflies’ superpowers — specifically, the ability to digest milkweed toxins and become poisonous to predators. Making just three genetic changes turned regular fruit flies into “monarch flies,” able to withstand plant toxins and store the chemicals as the flies transformed from maggots to adults, researchers report October 2 in Nature. Researchers previously had suspected that three amino acid changes in a protein called the sodium pump alpha subunit, or ATPalpha, were involved in making butterflies insensitive to chemicals known as cardiac glycosides, which are found in milkweed and some other plants. The sodium pump is part of a cellular system that moves charged sodium and potassium atoms in and out of cells. But it still was possible that the changes were just coincidental. So evolutionary biologist Noah Whiteman of the University of California, Berkeley and colleagues used the gene editor CRISPR/Cas9 to alter the sodium pumps of fruit flies and retrace the evolutionary steps that resulted eventually in monarchs becoming resistant to the chemicals. Monarchs store some of the chemicals in their bodies, making them poisonous and unpalatable to predators. Changing amino acids one at time, the researchers discovered that all three are needed to produce fruit flies that, from the egg stage through adulthood, can survive exposure to the chemicals. Milkweed tolerance has its price, though. Monarch flies became temporarily paralyzed when the vial they were contained in was banged on a table, an indication that the flies’ nervous systems were less able to handle to stress. That cost may be worth it for monarch butterflies because the benefit of being noxious to predators is so much more valuable, Whiteman says.
10-2-19 Sea of Shadows: Film documents demise of the world's smallest porpoise
Decimated by illegal fishing for the totoaba fish, the vaquita is the victim of global organised crime. Can a powerful new documentary improve its chances? THE documentary Sea of Shadows is the story of the world’s smallest porpoise, the critically endangered vaquita, which is hiding out in the extreme south-western corner of its territory in the Sea of Cortez off Mexico. It isn’t a story that will end well, though Richard Ladkani, whose 2016 Netflix documentary The Ivory Game was shortlisted for an Oscar in the 89th Academy Awards, has made something that is very hard to look away from. This isn’t an environmental story, but a true crime. No one wants to hunt the vaquita. The totoaba fish, which shares the vaquita’s waters, is another matter. It is known as the cocaine of the sea, a nickname that only makes sense once you learn that Mexican drug cartels have moved into the totoaba business to satisfy the Chinese luxury market, where the fish’s swim bladders are said to have rare medical properties. Illegal gill nets that catch the totoaba also catch and kill vaquitas. The Mexican government talks a good environmental game but has let the problem get out of hand. Law-abiding fishing communities are ruined by blanket fishing bans while the illegal fishers operate with near-impunity. Late on in the film, there is CCTV footage of a couple of soldiers with car trouble. They ask for help from a passing motorist, who shoots one of the soldiers dead and drives away. Meet Oscar Parra Aispuro, the totoaba padron of Santa Clara. (I said you couldn’t look away; I didn’t say you wouldn’t want to.) Things are so bad, a scheme is dreamed up to take the vaquitas out of the ocean to live in captivity. It is an absurdly desperate move because virtually nothing is known about the vaquita or its habits. Some locals believe the creature is a myth dreamed up by a hostile government to bankrupt the poor: how’s that for fake news? Project leader Cynthia Smith explains the dilemma facing the vaquita: “possible death in our care or certain death in the ocean”. She knows what she is doing – she is a senior vet for the US Navy Marine Mammal Program – but no one has ever tried to capture, let alone keep, a vaquita before.
10-2-19 Scare stories of mutant GM mosquitoes aren’t true, but have some truth
Tales of hybrid super-mosquitoes produced by a GM trial in Brazil are way off the mark – but our careless ways do create mutants that harm us, says Michael Le Page. DEADLY ‘super mosquitoes that are even tougher’ accidentally created by scientists after bungled experiment,” shouted The Sun in the UK. “Plan to kill off mosquitoes backfires, spawning mutant hybrid insects,” screamed the New York Post in the US. These headlines appeared last month, in response to a critical study of a trial carried out in Brazil from 2013 to 2015. It released millions of genetically modified male Aedes aegypti mosquitoes, which transmit serious diseases such as dengue, yellow fever, Zika and chikungunya. The mosquitoes carried an added gene meant to kill their offspring and thus wipe out wild mosquitoes. The shocking headlines aren’t true, but do contain an element of truth. We have created mutant mosquitoes, but not because of any genetic engineering mishap. That story begins in West African forests a few thousand years ago. There, female A. aegypti xdrank the blood of many species. Over time, these mosquitoes evolved a separate subspecies that fed on humans. In the 15th century, slave ships carried them to the Americas. From there, they reached every tropical region, allowing diseases like yellow fever to spread to these places too. Now, these mosquitoes are developing resistance to the pesticides we rely on to control them. Such is the backdrop for the Brazil trial, led by a company called Oxitec. It is true that the “lethal” gene fails to kill up to 5 per cent of the offspring of released males and wild females. Oxitec says regulators in Brazil knew this before the trial got the go-ahead. It is also true that the males derive from Cuba and Mexico, so the survival of a small percentage of their offspring creates a mix of three closely related strains of the same A. aegypti subspecies. Yet calling these hybrids is a stretch, and there is no reason to think they pose a greater threat, as some have claimed.
10-2-19 Dog behaviors like aggression and fearfulness are linked to breed genetics
A study looking at 101 breeds finds strong ties between certain behaviors and genes. Your dog’s ability to learn new tricks may be less a product of your extensive training than their underlying genetics. Among 101 dog breeds, scientists found that certain behavioral traits such as trainability or aggression were more likely to be shared by genetically similar breeds. While past studies have looked into the genetic underpinnings of dog behaviors for certain breeds, this research — published October 1 in the Proceedings of the Royal Society B — is the first to investigate a wide swath of breed diversity and find a strong genetic signal. “Anecdotally, everyone knows that different dogs have different behavioral traits,” says Noah Snyder-Mackler, a geneticist at the University of Washington in Seattle. “But we didn’t know how much or why.” Humans and dogs have lived together for at least 15,000 years (SN: 7/6/17). But only within the last 300 years or so have breeders produced varieties such as Chihuahuas and Great Danes. So, Snyder-Mackler and his colleagues considered how 101 dog breeds behave while searching for genetic similarities among breeds sharing certain personality traits. Data came from two dog genotype databases and from C-BARQ, a survey that asks owners to rank their pure-bred dog’s propensity for certain behaviors, like chasing or aggressiveness toward strangers. As a result, the study didn’t have genetic and behavioral data from the same canine individuals, which could help highlight rare genetic variants that may be nonetheless important to diversity in behaviors. (Webmaster's comment: Just like in the human male.)
10-2-19 Huge amounts of illegal wild meat from the Amazon are sold in Brazil
There is a roaring trade in wild meat from the Amazon rainforest in big cities in Brazil, even though it is illegal. The economic value of the wild meat trade is now comparable to the timber trade. While the trade poses risks to some species, it hasn’t pushed them to a crisis point as it has in parts of Africa and Asia, says Thaís Morcatty at Oxford Brookes University, UK. “We can draw a different story,” she says. “We see a potential for regulating the activity.” Morcatty and her colleagues surveyed 1046 households in five cities in the Brazilian state of Amazonas, which is almost entirely covered in the dense forest of the Amazon. They found that 80 per cent of interviewees ate some wild meat, on an average of 29 days per year. Most of them bought the meat from local markets or other traders. Assuming the cities sampled are typical, the team estimates that up to 10,691 tonnes of wild meat are eaten every year in the Amazon’s 62 cities. Based on the value of the meats, that means the wild meat trade could be worth $35.1 million per year – on a par with the mineral and timber trades in the area. The team identified 21 species that were being eaten. The most eaten by weight were pig-like animals called white-lipped peccaries, Brazilian tapirs, rodents called lowland pacas, and yellow-spotted river turtles. The animals are caught by rural people living in isolated regions of the Amazon rainforest, who then sell them on. “These people are not bad,” says Morcatty, because they are typically good stewards of the forest. Many grow crops, but this is seasonal so in some months they have no other income. However, some of the species, like tapirs, are long-lived and slow to reproduce, which makes them vulnerable to population crashes if they are overhunted.