4-19-19 A scientist used chalk in a box to show that bats use sunsets to migrate
Oliver Lindecke devised a new device that was partly inspired by a snow-covered Berlin street. When it comes to migration science, birds rule. Although many mammals — antelopes, whales, bats — migrate, too, scientists know far less about how those animals do it. But a new device, invented by animal navigation researcher Oliver Lindecke, could open a new way to test how far-ranging bats find their way. Lindecke, of Leibniz Institute for Zoo and Wildlife Research in Germany, has been studying bat migration since 2011. He started with analyzing different forms of hydrogen atoms in wild bats to infer where they had flown from. But figuring out how the bats knew where to go was trickier. Lindecke needed a field setup that let him test what possible cues from nature helped bats navigate across vast distances. The first step was studying in which direction the bats first take flight. Such experiments on birds typically involve confining the animals in small, enclosed spaces. But that doesn’t work for bats, which tend to fall asleep in such spaces. “My challenge was to build a box that bats won’t sleep in, but will show me how they take off,” Lindecke says. So he invented what he calls the circular release box: a flat-bottom, funnel-shaped container topped by a wider lid. To escape, the bat crawls up the wall and takes off from the edge. Bat tracks in a layer of chalk (Lindecke says he was inspired by a snow-covered Berlin street) indicate where the bat took off. In August 2017, Lindecke captured 54 soprano pipistrelle bats (Pipistrellus pygmaeus) in a large, 50-meter-wide trap at the Pape Ornithological Research Station in Latvia as the animals were migrating along the coast of the Baltic Sea toward Central Europe. Experiments with the new device showed that the adult bats flew straight in the direction in which they took off, Lindecke and colleagues report online March 1 in the Journal of Zoology.
4-19-19 Homeless Australian man reunited with lost rat pet by police
A homeless man in Sydney, Australia, has been reunited with his pet rat which disappeared earlier this month. Chris, 59, is a well known figure in downtown Sydney where the rat, called Lucy, is usually curled up on a box in front of him. But one day his little companion disappeared as he stepped away to take a toilet break. After a social media appeal, New South Wales police tracked down the missing pet and reunited the pair on Thursday. Chris had assumed Lucy was stolen after she disappeared from the milk crate where he'd left her. Desperate to find her, he put a note up on his box, asking if anyone had seen her. What followed was an outpouring of support, with people posting their own pictures of the pair, hoping that someone had seen Lucy or the person who'd taken her. Police appealed for information, believing Lucy had been stolen, but eventually found the missing rodent. "A woman, who walked past and saw Lucy alone, believed she had been abandoned, so took her home and cared for her," police said in a statement. Lucy was returned to Chris at a local police station on Thursday. When officers asked him to make sure they had got the right animal he replied: "Yes, that's her! She's got the blind eye. She remembers me!" Picking her up from a cardboard box, Chris was visibly relieved, thanking the officers for their efforts. "Sorry for putting you all through the trouble of looking for her. "It feels wonderful. Thank you very much, everybody," he said as his little furry friend scurried around his shoulders. "She knows she's missed me too."
4-17-19 Parenting chores cut into how much these bird dads fool around
Black coucals are one of the few avian species where only males care for chicks. The extreme dads of the bird world do all the work raising chicks while females fight intruders. The result: Male black coucals don’t sleep around as much when busy parenting. On occasion, a male black coucal (Centropus grillii) slips over to another male’s nest to sire a chick. The demands of incubating eggs, however, reduce a male’s excursions about 17 percent, on average, compared with male birds that didn’t have chicks. And during the frantic first week of parenting after eggs hatch, those philandering excursions drop by almost 50 percent, researchers report April 10 in the Proceedings of the Royal Society B. That’s when male coucals, native to sub-Saharan Africa, spend much of their days catching grasshoppers, frogs and other critters to feed chicks too frail to leave their woven grass nests, says behavioral ecologist Wolfgang Goymann at the Max Planck Institute for Ornithology in Seewiesen, Germany. Even when chicks can leave the nest, they’ll need at least two more weeks of dad’s care. These coucals are among the few bird species in which females, rather than males, stake out territories and defend them from other females. The females are bigger than the males and warn interlopers with “hoot, hoot” exchanges, which deepen in pitch if antagonists get closer. If hooting fails, one female will fly at the other bird to fight. “You see just the grass moving, and you hear a grumbling,” Goymann says. Sometimes he spots females “with huge wounds on their heads.” A female’s territory has up to five males nesting in it. She builds the basics of a nest and lays eggs with each male in her realm. Unlike other nestlings with dad-only care, these chicks hatch very early in development. They don’t even have enough fluff for warmth, and dad needs to snuggle them for about a week before they can leave the nest.
4-17-19 Rare kakapo parrots have best breeding season on record
Kakapos - the world's fattest species of parrot - have had their most successful breeding season on record, according to New Zealand's Department of Conservation (DOC). The flightless, nocturnal parrots were once one of the country's most common birds, but only 147 adults are left. This year, 76 chicks have been hatched under the DOC's conservation scheme, with 60 expected to reach adulthood. The new batch is more than double that of the last breeding season in 2016. Kakapos only breed every two to four years when their favourite fruit grows in New Zealand's Rimu trees - the period is known as a "mast year". Their numbers have also been curbed by hunting, deforestation, and predators like stoats which were introduced by European settlers. One scientific advisor to the DOC, Dr Andrew Digby, says scientists have seen bumper quantities of fruit on Rimu trees in recent years, an occurrence possibly caused by climate change. With so much fruit, many female kakapos have bred earlier and, in some cases, laid two clutches of eggs. Until the 1970s, kakapos were thought to be extinct but a group was discovered on Stewart Island, south of the country's South Island. Just 18 were known to exist by 1977, but New Zealand's DOC has spearheaded efforts to boost its population on two remote, predator-free islands. Under the scheme, all newborn kakapo chicks are raised in a secure facility and later released into the wild, tagged with a transmitter. Each parrot also has its nest fitted with sensors and cameras, and is given a tailored diet via nearby feeding stations. "They don't get a lot of privacy," Dr Digby said. "I can log online and see what they're doing, see who they've mated with, how long for, and even the quality of the mating. "It's probably one of the most intensively managed species in the world, certainly in New Zealand." (Webmaster's comment: 147 adult is not a viable population. Their culture has also been destroyed.)
4-14-19 Baby boom for North Atlantic right whales off US coast
One of the world's most endangered whale species is experiencing a mini baby boom off the US state of Massachusetts. Researchers at the Center for Coastal Studies have announced they have seen three North Atlantic right whale mother and calf pairs in Cape Cod bay. The whales give birth off Georgia and Florida in the winter before moving up the US east coast in the spring. Only about 450 of the species are believed to remain. Scientists reportedly did not spot any right whale newborns in 2018, so researchers were elated to report the sighting of two pairs of right whales in Cape Cod bay this week. The Scientist magazine reports that seven calves have been spotted off Florida so far this year. North Atlantic right whales were hunted virtually to extinction by the early 1890s, and have been listed as endangered since 1970. The mammals tend to stay near to coasts and have a high blubber content, making them a valuable target for whalers. It remains illegal to come within 500 yards (457 metres) of a North Atlantic right whale without a Federal Research Permit. There are three species of right whale around the world. The Southern right whale can be found throughout the southern hemisphere, and several thousand are thought to remain. But the North Pacific right whale is even rarer than its North Atlantic relative. The National Oceanic and Atmospheric Administration reports there are likely fewer than 200 left.
4-13-19 The history of dog breeds
Modern dog breeds were created in Victorian Britain. The evolution of the domestic dog goes back tens of thousands of years — however, the multiple forms we see today are just 150 years old. Before the Victorian era, there were different types of dog, but there were not that many, and they were largely defined by their function. They were like the colors of a rainbow: variations within each type, shading into each other at the margins. And many terms were used for the different dogs: breed, kind, race, sort, strain, type, and variety. By the time the Victorian era came to an end, only one term was used — breed. This was more than a change in language. Dog breeds were something entirely new, defined by their form and not their function. With the invention of breed, the different types became like the blocks on a paint color card — discrete, uniform, and standardized. The greater differentiation of breeds increased their number. In the 1840s, just two types of terrier were recognized; by the end of the Victorian period, there were 10, and proliferation continued — today there are 27. The advent of dog shows drove the creation of breed. The groups running these events and driving changes were styled the "dog fancy," and the aficionados of the new canines "doggy people." Breed standards were contingent and contested, decided as competitions selected the best dogs in each class. Owners gained prestige, and some income, from sales and stud fees. Competition at shows and in the market drove specialization, in the specification of ideal forms; standardization, in the designs of physical conformations; objectification, in viewing dogs' bodies as made up of parts; commodification, in promoting dogs as tradable goods; differentiation, in the proliferation of breeds; and alienation, as ability and character became secondary to form. The templates for breed conformation standards drew upon history, art, natural history, physiology and anatomy, and aesthetics. There was a tension in breeding between earned and inherited worth, that is, between "best in breed" winners, chosen in competitions, and "pure blood" dogs with pedigrees showing superior inheritance.
4-12-19 An amphibian apocalypse
A disease that has ripped through the world’s amphibian species—killing frogs, salamanders, and other creatures by eating away at their skin and triggering heart failure—is more than twice as deadly as scientists thought. Previous research into chytridiomycosis, which is caused by a fungus that’s invisible to the naked eye, estimated that the disease had caused the decline or extinction of some 200 frog species. But the new research concludes that the fungus has in fact caused declines in at least 501 amphibian species, nearly 7 percent of the known total. Of these, 90 species are presumed or confirmed extinct, and another 124 have experienced population declines of more than 90 percent. Species in tropical areas of Australia, South America, and Central America have been hardest hit, but North America, Europe, and Africa have also seen losses. “It’s a staggering thing to consider,” study co-author Jonathan Kolby, from James Cook University in Australia, tells The Washington Post. “We’ve never before had a single disease that had the power to make multiple species extinct, on multiple continents, all at the same time.” The declines have almost certainly affected ecosystems around the world: Many amphibians clear waterways of vegetation while in the tadpole stage of development; frogs can help keep mosquito numbers down by eating their larvae.
4-10-19 The forgotten riches of the most densely biodiverse country on Earth
THE AK-47 rifles hanging at the waists of the camo-clad visitors suggested they had little interest in birds. For ornithologist Andrés Cuervo, the knock at his cabin amid the isolated mountains, rivers and waterfalls of the Serranía de San Lucas region heralded just one of many unnerving encounters that punctuated his work. “Nobody knew the guerrillas were there, but they knew everything about us,” he says. For decades, this region of northern Colombia was one of many disputed in a civil war that left 260,000 people dead and 7 million displaced. What was a human tragedy proved a boon for biodiversity, however, as the conflict zones were spared the exploitation that ravaged similar environments elsewhere. Now, with the conflict largely at an end, at least officially, biologists such as Cuervo are returning in force to discover, record and understand the country’s astonishing lifeforms, and perhaps to unlock the secrets to novel medicines. But new threats are gathering force. They may not have much time. Colombia is by some measures the most biodiverse nation on Earth. It lags behind only Brazil in the total number of species it hosts, but has more species per square kilometre. It is thought to be home to nearly one in 10 of every type of the world’s flora and fauna, and there are more kinds of bird, amphibian and butterfly here than anywhere else. That is down to geography: bordering both the Atlantic and the Pacific oceans, the country lies at the northern end of the Andes mountains, which splits into three parallel ranges, the Western, Central and Eastern Cordilleras. This creates a unique patchwork of environments, from boggy moors to dense Amazonian forests and ice-capped peaks to Caribbean mangrove swamps. The remote Serranía de San Lucas massif lies in the Bolivar department at the northern tip of the Central Cordillera. Its highly diverse tropical rainforest marks where the mountains meet the Caribbean plains. For Cuervo, head of collections at the Humboldt Institute headquartered in Colombia’s capital, Bogotá, what drew him there despite the risks was the region’s 350-odd known species of bird. Similar riches attracted colleagues working in other fields.
4-9-19 Wolves return to Netherlands after 140 years
The Netherlands has its first resident wolf population in 140 years, according to ecologists. Wolves were hunted out of many European countries over a century ago but have gradually been migrating back across the continental mainland. Occasional wolf sightings have been made in the Netherlands since 2015. But these animals were previously thought to be animals that had crossed over temporarily from Germany and would subsequently return there. Ecologists from campaign groups FreeNature and Wolven in Nederland have been tracking two females in the Veluwe area, collecting wolf prints and scat (droppings) from which they can identify DNA."It's like Tinder," said ecologist Mirte Kruit, "it can say if it's a male or female, are they single and looking for a mate and [tell you] about their family." They've told BBC Radio 4's Costing the Earth that their data now confirms one of the females has stayed continuously for six months and can now be considered "established". A male has also been seen in the area so the first Dutch wolf pack could be months away. They are still collecting data on the second female. Wolves are controversial, however. In France, since returning from Italy in 1992, their population has grown rapidly and sheep and goat farmers say they're suffering rising attacks, with around 12,000 incidents reported. Farmers can receive compensation if they have protection measures in place, like electric fences or guard dogs, but many are still angry about the damage caused to the flock. The French Government formed a cohabitation plan and in February last year set a target wolf population of 500 by 2023. However its thought this number may be reached or surpassed by this Winter and it's proposing to increase the cull rate from 12% to 17% if that's confirmed. 4-7-19
Will the tiny inherit the Earth?
Bigger species have all the advantages. But they might just be outlived. As I scuba dive in Oslob Bay off Cebu Island in the Philippines, I see a tiny shadow dart over the surface of the spherical coral block — a minute fish, a goby of the genus Eviota, among the smallest vertebrates in existence, only about a centimeter long and weighing less than 1/10th of a gram. It's about a million times smaller than myself, with the same basic vertebrate body: a spinal cord, a bony skull, a brain, kidneys, and a liver. With the exception of gills and lungs, the tiny fish and I share similar sets of organs, just at a very dissimilar size. But looking at gobies is not why I came to Oslob. I leave the coral block, and swim towards the shore as the sun darkens — not because of clouds but, rather, a truly gigantic fish swimming directly above me. It's what I had hoped to see: a whale shark, Rhincodon typus, the largest living fish. Large adults weigh up to 34 tons, more than 300 times my own weight. The difference in weight between the tiny goby and the whale shark is a startling eight orders of magnitude. Some truly gigantic animals populate the Earth. These massive disparities in animal sizes have fascinated biologists for more than a century. And there are enormous advantages that come with being large. Big animals have an easier time avoiding predators: Some of the tiny gobies have an attrition rate to predation of more than 6 percent per day, while whale sharks live for decades, and are known to have survived tiger shark attacks. Bigger animals can also invest more in reproduction: While a female goby's body produces only about 250 tiny eggs per lifetime to hatch into larvae, a female whale shark can give birth to a few hundred fully developed shark pups in a lifetime, each more than half a meter in length. And there are more advantages to a big body size. In large warm-blooded animals, maintaining a constant body temperature is easier due to their better surface-to-volume ratio. And in large herbivores, the larger volume of the intestines leads to more effective fermentation processes, which are needed to break down plant material. It pays to be big. Indeed, many lineages of animals have vastly increased in size during the course of their evolution. This trend is called Cope's rule, named after the 19th-century paleontologist Edward Drinker Cope. Prominent examples of lineages following Cope's rule are dinosaurs, which originated from an already sizeable two-meter-long reptile alive in the mid-Triassic (231 million years ago). During the following 165 million years, dinosaurs evolved into the largest land animals ever, the Titanosaurs (up to 37 meters long), and the largest land predator ever, the mighty Tyrannosaurus rex. Another striking example are the cetaceans: whales and dolphins. These secondary marine mammals descended from a cat-sized amphibious omnivore roaming around India 48 million years ago called Indohyus. When becoming fully aquatic, the cetaceans' size increased, with the ancient Basilosaurid whales 41 million years ago already up to 25 meters long. The size increase of baleen whales further accelerated during the past 10 million years, and today's blue whale is the largest animal to ever live, with adults attaining lengths of up to 30 meters and weighing close to 200 tonnes. Given all these advantages of large body sizes, an obvious question to ask is: Why aren't all animal species big? One reason is that species of small animals give rise to new species more rapidly. In a recent theoretical study, we connected the well-established fact that small animals are more numerous (there are more gobies than whale sharks in the ocean) to the insight that larger populations give rise to new species — a process called speciation — at a faster rate.
4-4-19 Pet cats know their names they just sometimes prefer to ignore you
Most cat owners know the hopeless feeling of trying to call the name of their beloved pet, only to be ignored or, even worse, abandoned with a dismissive flick of the tail. An analysis of feline behaviour has found that cats really do know their names, it seems they just don’t care when you use them. Astuko Saito at Sophia University in Japan and her colleagues wanted to see if pet cats could distinguish between their own name and other similar-sounding words, even when a stranger called the name. The team visited cat cafes, where the pets mingle with diners, and households and analysed the way the animals’ ears, heads, tails and feet moved in response to the sound of various words. With the owner out of sight, they played recordings of the owner saying four words with the same length and accent as their cat’s name, 15 seconds apart. This was followed by a recording of the cat’s name. Many of the cats were likely to become accustomed to the sounds being made, so if they did really recognise their name, Saito and her colleagues believed they would see a different reaction when it was spoken. In the experiment, 11 out of 16 cats showed a drop off in activity between the first and the fourth word being spoken, suggesting they were getting used to the recordings. Of those 11, nine reacted again when their name was played. Cats who didn’t grow accustomed to the words were excluded from the analysis. When Saito performed the same test with a stranger’s voice, this time 20 cats became habituated to the words and 13 of these responded again to their own names. As for why cats don’t always come when called, Saito says they are just ignoring you.
4-4-19 Cats recognize their own names
A study suggests our feline friends can tell the familiar sound of their name from other words. Whether practical, dramatical or pragmatical, domestic cats appear to recognize the familiar sound of their own names and can distinguish them from other words, researchers report April 4 in Scientific Reports. While dog responses to human behavior and speech have received much attention (SN: 10/1/16, p. 11), researchers are just scratching the surface of human-cat interactions. Research has shown that domestic cats (Felis catus) appear to respond to human facial expressions, and can distinguish between different human voices. But can cats recognize their own names? “I think many cat owners feel that cats know their names, or the word ‘food,’” but until now, there was no scientific evidence to back that up, says Atsuko Saito, a psychologist at Sophia University in Tokyo and a cat owner. So Saito and her colleagues pounced on that research question. They asked cat owners to say four nouns of similar length followed by the cat’s name. Cats gradually lost interest with each noun, but then reacted strongly to their names — moving their ears, head or tail, shifting their hind paw position or, of course, meowing. The results held up with cats living alone, with other cats and at a cat café, where customers can hang out with cats. And when someone other than the owner said the name, the cats still responded to their names more than to other nouns. One finding did give the team pause. Cat café cats almost always reacted to their names and those of other cats living there. Housecats did so much less frequently. Lots of humans visit cat cafés, and cats’ names are frequently called together, so it may be harder for cats to associate their own names with positive reinforcement in these environments, the researchers write.
4-4-19 A major crop pest can make tomato plants lie to their neighbors
Whiteflies use plants’ chemical eavesdropping powers to get an easier meal. Don’t blame the tomato. Tiny pests called silverleaf whiteflies can make a tomato plant spread deceptive scents that leave its neighbors vulnerable to attach. Sap-sucking Bemisia tabaci, an invasive menace to a wide range of crops, are definitely insects. Yet when they attack a tomato plant, prompting a silent shriek of scents, the plant starts smelling as if bacteria or fungi have struck instead. Those phony odors prime neighboring tomato plants for an attack, but not from an insect, an international research team found. Those plants prepare to mount a fast and strong resistance against an incoming pathogen. But that high alert suppresses the plants’ chemistry for resisting insects and “leaves them far more vulnerable to the whiteflies when they arrive,” says Xiao-Ping Yu, an entomologist at China Jiliang University in Hangzhou. Tomato plants that spent 24 hours in a chamber with just the odor of a major whitefly attack managed to produce only half the surge of an insect-fighter hormone as plants taken by surprise by an insect attack, Yu and colleagues report March 25 in the Proceedings of the National Academy of Sciences. Plant defense chemistry often poses this one-or-the-other dilemma. To put up a good fight against insects, plants typically rev up a system of defenses controlled by the hormone jasmonic acid, or JA. But throwing that system into full gear suppresses the defenses controlled by salicylic acid, SA, which are more useful against pathogens.
4-3-19 A chimp's hug shows it's time to accept that animals have feelings too
In Mama’s Last Hug, primatologist Frans de Waal argues that we can no longer deny that animals have feelings and we need to look closely at their inner lives. UNTIL recently, it was heretical for a biologist to argue that animals have a mental life. Because animals can’t tell us what they are feeling, most scientists thought it safest to assume that they don’t feel much at all, or that their behaviours derive from simple instinct or learning. Emotions, empathy and intelligence were considered exclusively human traits – they were what defined us as human. Frans de Waal, who has been studying the behaviour of primates for more than four decades, has always opposed this view, which is still prevalent in some circles. For him, there has never been any question that animals experience the same emotions as humans. “Why did we go out of our way to deny or deride something so obvious?” he asks in his latest book, Mama’s Last Hug, written before he retires this year. “Considering how much animals act like us, share our physiological reactions, have the same facial expressions, and possess the same sort of brains, wouldn’t it be strange indeed if their internal experiences were radically different?” The title of de Waal’s book refers to a final reunion between Mama, a dying 58-year-old chimpanzee, and Jan van Hooff, a 79-year-old biologist who had known her for 40 years (the YouTube video of this event has been watched more than 10 million times since it was posted in 2016). When she realises who he is, Mama rouses herself from her lethargy, grins expansively and embraces van Hooff. It is hard not to interpret her reaction as sheer joy, and de Waal believes that we are right to do so. “Instead of tiptoeing around [the emotions], it’s time for us to squarely face the degree to which all animals are driven by them,” he writes.
4-3-19 Animal testing: US closes 'kitten slaughterhouse' after outcry
The US Department of Agriculture (USDA) says it will stop killing cats in a research programme, following strong public criticism. Cats and kittens have been used to research toxoplasmosis - a potentially deadly parasitic illness usually caught from cats or tainted food. The animals were fed infected meat, and the parasite's eggs harvested for use in other experiments. After the research the animals were euthanised. Veterinary groups say that the disease is treatable and the cats should have been adopted. More than 3,000 kittens have been put down since the programme was launched in 1982, campaigners the White Coat Waste Project (WCWP) say, with the programme costing more than $22m (£17m). In March, bipartisan legislation, known as the Kitten Act, was introduced in Congress to end the practice, describing it as "taxpayer-funded kitten slaughter". In a statement, the USDA said that "toxoplasmosis research has been redirected and the use of cats... has been discontinued and will not be reinstated". One of the key figures behind the bill, Democrat Representative Jimmy Panetta, said the announcement showed what was possible in politics. The 14 remaining cats on the programme are to be adopted by USDA employees. The department has said its research helped halve the rate of toxoplasmosis infections, which is particularly dangerous for unborn children and people with compromised immune systems.
4-3-19 Tiny pumpkin toadlets have glowing bony plates on their backs
Researchers suggest the structures may help the deaf frogs communicate. When a group of biologists realized that pumpkin toadlets had no middle ear bone, the team was stumped. That meant that these tiny, toxic frogs couldn’t hear each other’s high-pitched chirps, which is how most frogs attract mates. “We scratched our heads about how they could communicate by other means,” says Sandra Goutte, an evolutionary biologist at New York University Abu Dhabi in the United Arab Emirates. Suspecting that the frogs use a less obvious form of communication, similar to parrots attracting mates with feathers that emanate ultraviolet light (SN:1/19/02, p. 40), the researchers aimed a UV lamp at the frogs’ neon orange skin and saw a pattern glowing in blue. “I couldn’t stop smiling for the whole day” after discovering that the frogs had glowing bony plates just beneath the skin on their heads and backs, Goutte says. The finding, reported online March 29 in Scientific Reports, marks the first known case of an amphibian showing bone fluorescence. Among terrestrial vertebrates, only chameleons have been found with this trait. Skeletal and tissue comparisons of two toadlet species — Brachycephalus ephippium and B. pitanga — with a third frog relative revealed that the plates were skin that had turned to bone. All bone fluoresces under UV light, but usually layers of skin, muscle and fat block that light from getting out. The skin covering the frogs’ plates, however, is thin enough for the light to be seen, and it lacks pigmented cells called melanophores that help block UV light from getting through skin. These traits may allow the frogs to communicate with fluorescence, possibly for luring potential mates or warning would-be predators, the researchers suggest.