No matter where you look, just about every creature
is obsessed with:
sex, real estate, who's the boss, and what's for dinner.
28 Intelligence & Zoology News Articles
for October of 2018
Click on the links below to get the full story from its source
10-19-18 Old honeybees make a drumming sound to get young slackers working
he more experienced bees in a colony sometimes run around the honeycomb drumming with their bodies - which seems to energise younger colony members. Sometimes a honeybee hive is not quite buzzing, and the workers need a signal to get busy. For the first time, scientists have made extensive recordings of a drumming sound some honeybees make to order their colleagues to get to work. We’ve known about this “dorso-ventral abdominal vibration” (DVAV) signal for about 90 years, and some biologists have captured video of bees producing the sound – but these earlier studies have only monitored bees for short periods during the day. Now Martin Bencsik at Nottingham Trent University, UK, and his colleagues have analysed a year’s worth of data from devices that record vibrations in the honeycomb inside three hives, revealing more about the function of the message. Only some bees give the signals: they are thought to be older bees, who have more experience of foraging. “I think they are the most mature, wisest elements of the colony,” says Bencsik. About 70 per cent of the time, a bee makes the signal by vibrating its abdomen while grasping another bee with its legs to transfer the message. On other occasions, they deliver the vibration directly onto the honeycomb. The transmitter bee sometimes runs around the hive, delivering the signal many times in quick succession to reach a large number of other bees. The effect the signal has on individual recipients is hard to judge, but overall, it has been shown to activate the colony. “The recipient bee seems to be energised,” says Bencsik. “She gets on with her job with more energy, as if she has had coffee or something.”
10-18-18 Mantis shrimps punch with the force of a bullet – and now we know how
The mantis shrimp has an incredibly fast punch, and it’s because of a structure called a saddle that stores energy and then releases it like an archer's bow. The mantis shrimp packs a mean punch, smashing its victims’ shells with the force of a .22 caliber bullet. But that’s not because it has particularly powerful muscles – instead of big biceps, it has arms that are naturally spring-loaded, allowing it to swing its fistlike clubs to speeds up to 23 metres per second. We know that the key part of a mantis shrimp’s punch is a saddle-shaped structure on the arm just above the shrimp’s club. This shape works a bit like a bow and arrow, says Ali Miserez at Nanyang Technological University in Singapore: the muscles pull on the saddle to bend it like an archer’s bow, and when it is released that energy transfers into the club. Miserez and his colleagues used a series of tiny pokes and prods, as well as a computer model, to examine exactly how the shrimp’s saddle holds all that energy without snapping. They found that it works because of a two-layer structure. The top layer is made of a ceramic material similar to bone, and the bottom is made of mostly plastic-like biopolymers. When the saddle is bent, the top layer gets compressed and the bottom layer is stretched. The ceramic can hold a lot of energy when it is compressed, but is brittle when bent and stretched. The biopolymers are stronger and stretchier, so they hold the whole thing together. “It explains how the shrimps’ appendage breaks things without breaking itself,” says Foivos Koukouvinis at City University of London in the UK.
10-17-18 Dandelion seeds create a bizarre whirlpool in the air to fly
When you’re essentially a little ball of floof, flying is hard. Hairlike filaments help spawn the swirling vortex and create drag. To ride the wind, dandelion seeds stir up a weird type of whirlpool in the air directly above them. The newly discovered way of moving through the air, described October 17 in Nature, resolves a long-standing question about how the seeds stay aloft. Dandelion seed flight is not unlike the flight of Mary Poppins: Utterly charming, yet inexplicable when it comes to physics — until now. When a gust of wind plucks a seed from the plant’s fuzzy head, a fluffy structure called the pappus keeps the seed aloft before it ultimately falls to the ground. The structure, which extends from the seed, is made up of tiny hairlike filaments, making it mostly empty space. “It’s a weird structure,” says coauthor Naomi Nakayama, a biophysicist at the University of Edinburgh. “Nobody really knew how it could fly.” So Nakayama and her colleagues dug into the weeds. High-speed video and mathematical simulations revealed that the pappus filaments act together like a uniform sheet or a parachute and create drag — a force that counters gravity. Air also flows around the pappus and gets sucked into the area just above it. This air forms a swirling bubble that the researchers call a separated vortex ring, which adds to the drag.
10-17-18 A long walk: New insight into history of dogs and humans
Dogs were part of a key moment in human history - when our ancestors began trying their hand at farming. As the first farmers moved out of the Middle East, herding animals such as sheep and goats, dogs tagged along too, say scientists. The DNA evidence fills in some of the gaps in the story of how wolves became the dogs of all shapes and sizes that we know today. Farming began in what is known as the Fertile Crescent of the Middle East. This includes parts of modern-day Iraq, Syria, Lebanon, Jordan, Israel and Egypt. Humans who were living as hunter-gatherers settled down and started growing wild varieties of crops like wheat, barley, peas and lentils. They also domesticated animals from wild sheep, cows and pigs. About 9,000 years ago, they moved into Europe and Asia, taking their animals and farming know-how with them. The new study shows their dogs also went on the trip. The evidence comes from DNA extracted from canine remains found at archaeological sites across Europe and Asia. "Our study shows that dogs and humans have an intertwined story - dogs followed humans during this migration across Europe," said Dr Morgane Ollivier of the University of Rennes in France. "We show in this paper that dogs and humans were already really connected." When the dogs arrived in Europe, they mixed with the dogs that were already there, changing the gene pool. Centuries of dog breeding have mixed up the genes of dogs further. Modern dogs, of all shapes and sizes, are very different now to those early farm dogs who accompanied their owners on their travels.
10-17-18 Tasmania penguin deaths: Dozens killed in suspected dog attack
Wildlife officials are investigating a suspected dog attack in Tasmania, after 58 penguins were found mauled to death. A member of the public alerted rangers to the dozens of penguin bodies strewn across a beach on the north coast of Australia's island state. This is the second dog attack in months on local little penguins - the smallest penguin species - according to reports. Authorities said dog owners must take responsibility for their pets and earlier warned of hefty fines. "We would like to remind dog owners of the need to take responsibility for their animals at all times as dogs have the capacity to do a lot of damage to penguin colonies in a short period of time," Tasmania's department of parks, water and environment said in a statement. It said all reports of alleged unlawful harming of wildlife would be taken "extremely seriously" and encouraged anyone with information to come forward. According to a local wildlife expert, the birds attacked earlier this week were returning to their nests for the start of breeding season. "This will have a catastrophic impact on the colony," BirdLife Tasmania convenor Eric Woehler told the Australian Associated Press. "It's going to take a long time, years, for those breeding birds to be replaced."
10-17-18 Male birds can be good singers or good looking, but not both
The prettier the bird, the worse it sings. A study of over 500 species has revealed that birds evolve to attract mates in one of two ways, and don’t combine them. The call of a male peacock is no pleasure to listen to, but its splendid tail means it doesn’t matter. Now an analysis of more than 500 species shows that this is a common trade-off in the bird world: the best lookers aren’t the most talented singers, while the best vocalists aren’t as easy on the eye. Sexual selection is an evolutionary process that shapes traits that animals use to attract mates, and birds are well known to resort to elaborate songs and flashy feathers in the name of reproduction. To investigate which species use which traits, Christopher Cooney at the University of Oxford and his colleagues collected the songs of 518 species, and compared these with their feather colours. In particular, they looked at how much feathers differed between the males and females of each species – a sign that sexual selection has influenced their plumage. They found that birds in which one sex has more showy plumage than the other tend to have less interesting, more monotonous songs. In species in which the males and females more closely resemble each other, the males sing longer songs over a larger range of musical notes.
10-15-18 In cadaver caves, baby beetles grow better with parental goo
Parental gut microbes can turn a small dead animal into a healthful nursery. Growing up inside a dead mouse could really stink, but not for some burying beetles. Their parents’ gut microbes keep the cadaver fresh, creating a nursery where the larvae can thrive. What burying beetle parents can do with a small dead animal is remarkable, says coauthor Shantanu Shukla of the Max Planck Institute for Chemical Ecology in Jena, Germany. “It looks different. It smells different. It’s completely transformed by the beetles.” The carrion beetles Nicrophorus vespilloides start family life by burying a small dead vertebrate, which they keep fresh enough for baby food. Parents open a little flesh-cave in the cadaver, and hatchlings creep in to gorge. As the beetle youngsters grow inside this, the parents regularly refresh a dark microbial film inside the cavity. That helpful goo is not the usual slime that blooms in carcasses but resembles the parent beetles’ gut microbiomes, Shukla and colleagues report October 15 in the Proceedings of the National Academy of Sciences
10-15-18 Rabbit-killing virus may have mutated to kill hares too
Brown hares are turning up dead across the UK, raising fears that myxomatosis – the rabbit infection in ‘Watership Down’ - may have mutated to target hares. Brown hares are turning up dead across the UK, leading to fears that the highly infectious rabbit-culling disease myxomatosis has jumped species. Myxomatosis, caused by the myxoma virus, was introduced to rabbits in Australia and Europe in the 1950s to reduce their numbers. Its virulence proved effective and the disease tore through wild populations, killing 99 per cent of rabbits in the UK. Numbers bounced back as rabbits developed some degree of resistance but the disease, which is spread by blood-sucking insects like fleas and mosquitoes and can result in swelling, blindness and respiratory problems, is still prevalent. Now the University of East Anglia, together with the Suffolk Wildlife Trust and Norfolk Wildlife Trust, are warning that hares may be being targeted by a mutated form of the virus. UK sightings of dead hares are not the first indications that myxomatosis can affect these animals. There have been reports in recent years of the disease killing hares in Spain, for example. But the number of dead hares found over a short period of time in the UK – in one case six were found in a single field – has raised fresh concerns. If the disease were to hit hares as hard as it did rabbits in the 1950s, the effect could be devastating. Hares are much rarer than rabbits and there are currently fewer than 818,000 left in the UK according to the People’s Trust for Endangered Species – that’s 80 per cent fewer than there were 100 years ago. The UK Department for Environment, Food & Rural Affairs is yet to confirm that the dead hares died of myxomatosis. Another culprit is rabbit haemorrhagic disease, another viral infection thought to infect hares.
10-15-18 How nectar bats fly nowhere
The first direct measurements of wingbeat force show how hard hovering is. Flying forward is hard enough, but flying nowhere, just hovering, is so much harder. Most bats and birds can manage the feat for only a few frantic seconds. Hovering means losing a useful aerodynamic shortcut, says aerospace engineer and biologist David Lentink of Stanford University. As a bat or bird flies forward, its body movement sends air flowing around the wings and providing some cheap lift. For animals on the scale of bats and birds, that’s a big help. Without that boost, “you’re going to have to move all the air over your wings by moving it with your wings,” he says. The energy per second you’re consuming to stay in place by flapping your wings back and forth like a hummingbird “is gigantic.” So how do vertebrates in search of nectar, for whom a lot of energy-sucking hovering is part of life, manage the job? For the first direct measurements of the wingbeat forces that make hovering possible, Lentink’s Ph.D. student Rivers Ingersoll spent three years creating a flight chamber with exquisitely responsive sensors in the floor and ceiling. As a bird or bat hovers inside, the sensors can measure — every 200th of a second — tremors even smaller than a nanometer caused by air from fluttering wings. Once the delicate techno-marvel of an instrument was perfected, the researchers packed it into 11 shipping cases and sent it more than 6,000 kilometers to the wilds of Costa Rica. “Very difficult,” Ingersoll acknowledges. The Las Cruces Research Station is great for field biology, but it’s nothing like a Stanford engineering lab. Every car turning into the station’s driveway set off the wingbeat sensors. And even the special thick-walled room that became the machine’s second home warmed up enough every day to give the instrument a fever.
10-12-18 Killer whales under threat
At least half the world’s orca populations will become extinct within the next century, because of long-banned chemicals that are polluting the oceans, a new study has found. Polychlorinated biphenyls, or PCBs, were once widely used in electrical components, plastics, and paints, reports The Guardian (U.K.). They were banned in the U.S. in 1979, and in most other countries soon afterward, when PCBs were found to be highly toxic and carcinogenic. But the chemicals continue to leach into the sea from landfills and other sources, and the qualities that made them useful—stability and heat resistance—also make them hard to break down. They become more concentrated at each stage of the food chain, and at the top of the chain, consuming PCBs in the highest concentrations, are killer whales. Orcas are particularly vulnerable to the chemicals, which affect their immune system and hamper their ability to reproduce. After studying PCB levels in 351 killer whales, researchers concluded that populations of the mammal in the waters off Japan, Brazil, Hawaii, Gibraltar, and the U.K. “are all tending toward complete collapse.” Paul Jepson, from the Zoological Society of London, describes the decline as “like a killer whale apocalypse.”
10-12-18 Self-driving cars see better with cameras that mimic mantis shrimp vision
A new type of camera more clearly maps objects as the vehicle travels. To help self-driving cars drive safely, scientists are looking to an unlikely place: the sea. A new type of camera inspired by the eyes of mantis shrimps could help autonomous vehicles better gauge their surroundings, researchers report October 11 in Optica. The camera — which detects polarized light, or light waves vibrating on a single plane — has roughly half a million sensors that each capture a wide range of light and dark spots within a single frame, somewhat similar to how mantis shrimps see the world. The researchers wanted to “mimic the animals’ ability to detect a wide range of light intensities,” says coauthor Viktor Gruev, a bioengineer at the University of Illinois at Urbana-Champaign. The crustaceans’ visual system allows them to see both light and dark areas while moving in and out of dark crevices in shallow waters, he says. The newly devised camera can take in a wider range of light intensities, measured in decibels, than other digital or polarization cameras. Previously, the best polarization cameras operated with a dynamic range of about 60 decibels; the new one works within a 140 decibel range, resulting in a clearer mapping of objects in the same frame.
10-10-18 Bees suddenly stopped buzzing in the US during the 2017 solar eclipse
When the moon hid the sun in the 2017 total solar eclipse, bees across the US suddenly stopped buzzing around - only one bee aross 16 locations buzzed. During the solar eclipse that swept across North America last year, a set of 16 monitoring stations recorded bees suddenly going quiet in the period of totality, when the moon completely obscured the sun. Only one buzz was recorded across all of the microphones in the three-minute period surrounding totality. In August 2017, the moon obscured the sun in a total solar eclipse visible across the US. Candace Galen at the University of Missouri and her colleagues set up microphones in stands of flowers along the path of the eclipse, from Oregon to Missouri, to listen to bee activity. They found that as the moon moved over the sun’s face, the bees continued buzzing along. But in the period around the total eclipse, the sound, which is created by the bees’ wings as they fly, suddenly dropped off. “We had expected that we would see a reduction in activity, but we thought that it would be gradual following the loss of light,” says Galen. “We didn’t expect everything to just go along as usual until totality.” During totality, the buzzing completely stopped at all 16 microphones. The team recorded sound at each site for three minutes – covering the period of totality that lasted 40 to 160 seconds – and found that only one bee buzzed through the silence. “It could have been slow getting back to the hive, or a bee with particularly good eyesight,” Galen says. It’s not clear whether the bees flew back home to weather totality, like they do at night, or whether they sheltered in place in flowers, like they do in inclement weather. “Nobody was looking down at the bees on the flowers during totality,” says Galen. “All we can say is what they weren’t doing – they weren’t flying.”
10-10-18 What bees did during the Great American Eclipse
Rare study of pollinators during totality shows the insects responding to sudden darkness. When the 2017 Great American Eclipse hit totality and the sky went dark, bees noticed. Microphones in flower patches at 11 sites in the path of the eclipse picked up the buzzing sounds of bees flying among blooms before and after totality. But those sounds were noticeably absent during the full solar blackout, a new study finds. Dimming light and some summer cooling during the onset of the eclipse didn’t appear to make a difference to the bees. But the deeper darkness of totality did, researchers report Oct. 10 in the Annals of the Entomological Society of America. At the time of totality, the change in buzzing was abrupt, says study coauthor and ecologist Candace Galen of the University of Missouri in Columbia. The recordings come from citizen scientists, mostly school classes, setting out small microphones at two spots in Oregon, one in Idaho and eight in Missouri. Often when bees went silent at the peak of the eclipse, Galen says, “you can hear the people in the background going ‘ooo,’ ‘ahh’ or clapping.” (Webmaster's comment: Back before scientific understanding humans would pray, blame it on human sinners, and sacrifice virgins. Human response then was just as pre-programmed as the bees.)
10-10-18 Rabbits flee when they smell dead relatives in predators’ droppings
Rabbits avoid nibbling grass in areas scattered with predator droppings – particularly if those predators have been fed on bunnies. If you’re a rabbit, it’s important to recognise when predators are around. It’s even more useful to know if these predators are eating your friends. New research suggests that rabbits can do the latter by detecting the scent of other, now-digested rabbits in predator scat. European rabbits are particularly popular targets for predators – more than 30 species will eat them, says José Guerrero-Casado at the University of Cordoba, Spain. To cope with the constant threat, rabbits have evolved an impressive ability to recognise the scent of a predator that might want to eat a bunny. But Guerrero-Casado and his colleagues wondered if rabbits could identify the scent of a predator that already had. “The recognition of [other rabbits] in the predator scats would allow rabbits to avoid those areas with higher risk, feeding in other areas with a lower risk of being predated,” explains Guerrero-Casado. The researchers ran an experiment on three plots of land spread out across the Spanish countryside. One plot was sprayed daily with the smelly essence extracted from the scat of ferrets on a beef-based diet. Another plot was sprayed with the scat odour from ferrets on a rabbit-based diet. The third was sprayed with water as a control. Every few days, the team counted the rabbit pellets left behind on the plots and used the number as an indicator of how often rabbits were visiting the plots to feed.
10-10-18 Yellow makeover to help horses see jumps in BHA trial
Fences and hurdles in British racing are set for a major makeover after it was discovered horses see the obstacles differently to humans. At present, the framework for the jumps is painted orange but research has shown horses see the colour as a shade of green. Horse racing authorities have now agreed to try fluorescent yellow and white markers to aid visibility. A trial at training grounds will take place before any on-course changes. Research at the University of Exeter - funded by the British Horseracing Authority (BHA) and Racing Foundation - showed horses adjusted their jump angles when orange was not used, with white tending to produce a longer total jump distance. Ian Popham, a Grade One-winning former jockey who was involved in the research, said: "From riding over the different coloured fences it was clear to me that over some colours the horses reacted differently and showed the obstacle more respect. "I'm sure other riders will feel the same and this feels like a great idea and opportunity to make the sport safer for both horses and jockeys."
10-10-18 Pangolin survival: How 'following the money' could save lives
Around the world, the illegal wildlife trade is having a devastating effect on many species of animal. Targeting profits made by those involved could help protect them. Animals - both dead and alive - are being bought and sold on an industrial scale as food, pets, medicines and even ornaments. The trade affects a huge range of species from great apes to helmeted hornbills, but arguably none more so than the pangolin. These unusual-looking creatures are prized in some countries for their meat and scales and are thought to be the world's most trafficked mammal, with about 100,000 a year snatched from the wild and sent to Vietnam and China. Global attention is often focused on species such as elephants and rhinos - and in many countries the populations of these animals has plummeted. In Tanzania, for example, elephant numbers fell by 60% from 109,000 in 2009, to just over 43,000 in 2014, according to government figures. The hidden driver behind this trade is a basic one: the pursuit of profit. For each of these trafficked animals, money changes hands - across the palms of corrupt officials, between those involved in the trade on the ground and on the internet. Yet these money flows are often overlooked in the fight to curb the illegal wildlife trade. At a conference in London this week, financial approaches to dismantling the criminal networks involved will be discussed. Rather than "follow the money", the most common approach remains that of "follow the animal". This is despite the huge figures involved. Although impossible to calculate precisely, the illegal wildlife trade has been valued at somewhere between $7bn (£5.4bn) and $23bn (£17.6bn) a year. Much of this money is exchanged physically between individuals, but large amounts also pass through banks.
10-9-18 Home of the gentle giants: How humans live with Galapagos tortoises
The Galapagos archipelago is a growing tourist attraction, which is adding to the problems faced by the islands’ famous giant residents. The Galapagos are home to 10 types of giant tortoises. Lacking natural predators, they regularly grow to 400 kilograms and can live for a century. But despite their size they are not as easy to find as I had anticipated. Many regard the Galapagos as a living zoo, little changed since Charles Darwin visited here in the 1830s. The reality is starker. Climate change, invasive plants and animals – there are 1476 introduced species – and conflicts between humans and wildlife are among the many problems. The Galapagos National Park allows human settlements on only four islands and 97 per cent of all land here remains protected, but the human impact on the remaining 3 per cent is significant. I see it in the yapping guard dogs and the fences that protect crops and disrupt tortoise’s migratory routes and feeding patterns. Two to three million years ago, tortoises arrived from South America and quickly colonised the archipelago. They were once so plentiful that they gave the islands their name – tortoise in Spanish is Galapago. Now there are about 20,000 giants remaining according to some estimates, a far cry from the estimated 200,000 before the Galapagos were discovered in the 16th century. Four species went extinct because pirates and whalers prized their meat and oil. Trudging through slick mud, combing through thick corn stalks and thicker jungle, my only encounters so far have been with farmers and their cows, goats and chickens. I head further into the bush until the misty rain restarts. Tired and wet and yet to find a tortoise, I return to the road. Thirty minutes later I am on a packed bus, hurtling along the highway that slices through jungle, descending towards the town of Puerto Ayora.
10-5-18 Octopuses on ecstasy
Does the drug ecstasy make octopuses more friendly? That, strangely enough, is a question to which scientists now have an answer, reports The New York Times. The eight-tentacled invertebrates are notoriously smart—they can navigate mazes and unscrew jars to get food—and are also deeply antisocial. So when Gul Dolen, a neuroscientist at Johns Hopkins University, discovered that octopuses and people share the genes for a protein targeted by MDMA, the psychoactive substance in ecstasy, she decided to find out if the drug might change the animals’ behavior. She put an octopus in a tank with three connected chambers: one empty, one containing a Star Wars figurine, and one with another (caged) octopus. Without the MDMA, the cephalophod focused its attention on the action figure. But after taking low doses, the octopus spent much more time with its fellow invertebrate, even hugging its cage. Other octopuses displayed similar behavior: Some even became playful, doing what researchers described as “water ballet.” Dolen believes octopuses could be useful for studying the effects of MDMA, and for learning how the human brain evolved to respond with social behaviors. “Even though octopuses look like they come from outer space,” she says, “they’re actually not that different from us.”
10-5-18 Eliminating mosquitoes
Scientists have used gene-editing techniques to completely wipe out a population of mosquitoes in the lab, raising hopes that the experiment could be replicated on a wider scale to help eradicate malaria. Gene editing involves the alteration of a specific gene to create changes in the organism’s offspring. In this case, researchers from Imperial College London tweaked the doublesex gene, which determines whether a mosquito develops into a male or female. They then introduced these genetically modified insects into a caged population of Anopheles gambiae, the type of mosquito that spreads malaria in sub-Saharan Africa. The mutation blocked female reproduction but allowed males to keep spreading the alteration; the population collapsed within seven to 11 generations. More experiments are needed to find out if the method will work on larger populations, or with other types of mosquitoes; eliminating an entire species would also be fraught with bioethical and environmental concerns. But they’re nonetheless excited. “This is a game changer,” study leader Andrea Crisanti tells NPR.org. “This is a completely new era in genetics.”
10-5-18 Grizzly bears improve
About 700 grizzly bears currently live in the vicinity of Yellowstone National Park. When the animal was first placed on the Endangered Species Act list, only about 125 were known to be living in the area.
10-5-18 Modern dogs
Modern dogs, with new research suggesting that dogs crave eye contacts and become depressed and anxious when their owners spend too much time staring at smartphones.
10-4-18 Minnesota town alerts residents over 'tipsy' birds
A US town has warned its residents not to be too concerned about drunk-looking birds stumbling around town. Police in the northern Minnesota town of Gilbert say they have received reports of birds "flying into windows, cars and acting confused". The intoxicated state of the birds is due to berries fermenting ahead of time due to an earlier than usual frost. Younger birds cannot handle the toxins as well as older birds, local police chief Ty Techar said in a statement. "There is no need to call law enforcement about these birds as they should sober up within a short period of time," he added.
10-3-18 The colour blind octopus that mastered the art of disguise
The fact that the animals can copy vivid patterns that they can't even see is perplexing, but it turns out they might not be using their eyes at all. TWENTY metres underwater, off the coast of north-west Spain, biologist Roger Hanlon is stalking his prey. His camera is trained on a subject that has painted itself beige, grey and white to match the gravelly seabed. It perambulates towards a clump of kelp and, settling itself amid the fronds, quickly deepens its complexion to match their rich red-brown. This colour craft is impressive, but for Hanlon it is also baffling. He knows the common octopus is colour blind. At least, that is what the textbooks tell us. In his own recent book, Hanlon lists multiple arguments for the cephalopods – octopuses, squid and cuttlefish – seeing in monochrome. Yet if you ask him casually, he remains unconvinced: “I would tend to think that cephalopods are able to sense and match colour somehow.” Quite how they do it has confounded biologists for more than a century, though they have come up with some strange ideas to explain the conundrum. Now we are whittling down the spectrum of possibilities – in the hope of gaining an unprecedented insight into how these most alien of creatures see the world. Like Hanlon, the Nobel prize-winning zoologist Karl von Frisch didn’t believe cephalopods were colour blind. In the 1910s, he and the ophthalmologist Carl von Hess got into a debate about it. Hess tested the vision of squid and cuttlefish by trapping the animals in tanks so small they could barely move and flashing coloured lights at them. He noted how their pupils responded to the lights and if they tried, unsuccessfully, to swim away.
10-3-18 Lemur study suggests why some fruits smell so fruity
A new test with lemurs and birds suggests there’s more to fruit odors than simple ripening. It’s a lovely notion, but tricky to prove. Still, lemurs sniffing around wild fruits in Madagascar are bolstering the idea that animal noses contributed to the evolution of aromas of fruity ripeness. The idea sounds simple, says evolutionary ecologist Omer Nevo of the University of Ulm in Germany. Plants can use mouth-watering scents to lure animals to eat fruits, and thus spread around the seeds. But are those odors really advertising, or are they just the way fruits happen to smell as they ripen? For some wild figs and a range of other fruits in eastern Madagascar, a strong scent of ripeness does seem to have evolved in aid of allure, Nevo and his colleagues argue October 3 in Science Advances. A lot of fruit collecting and odor chemistry suggest that fruits dispersed by lemurs, with their sensitive noses, change more in scent than fruits that rely more on birds with acute color vision. Earlier studies had sniffed around several species, such as figs. But for a broader look, Nevo and his colleagues analyzed scents from 25 other kinds of fruits as well as five kinds of figs. All grew wild in a “really magnificent” mountainous rainforest preserved as a park in eastern Madagascar, Nevo says. The researchers classified 19 of the plants as depending largely on red-bellied and other local lemurs to spread seeds. Most of these lemurs are red-green color-blind, not great for spotting the ripe fruits among foliage. But the researchers following some lemurs foraging in daylight noticed that sniffing at fruits was a big deal for the primates.
10-2-18 Giraffes inherit their spots from their mothers
The animals' patterns of fur splotches may also indicate how well the tall creatures can survive. The mottled patterns that adorn Africa’s tallest creatures are passed down from their mothers, a new study suggests. A giraffe calf inherits spots that are similar to those of its mother in terms of roundness and the smoothness of the spots’ borders, researchers report October 2 in PeerJ. The size and shape of those splotches can also affect a giraffe’s chances of surviving in the wild, the team says. Giraffes — like tigers, zebras and jaguars — are covered in patterns that aid in regulating body temperature and help signal to other animals that they’re part of the same species. The markings also act as camouflage, optically breaking up the body shapes of animals to hide them from predators. Enthusiasts “kept asking us ‘Why do giraffes have spots?’ and ‘Do calves inherit their spot patterns?’ ” says Derek Lee, a quantitative wildlife biologist at Penn State who is also principal scientist at the Wild Nature Institute, which is based in Concord, N.H. “We didn't have any answers, so we used our data to get them.” Scientists previously have suggested that the patterns of animals’ spots and stripes are conferred at random, or that they’re influenced by environmental factors. Suspecting a hereditary link, Lee and colleagues spent four years photographing the coats of 31 mother-and-baby giraffe sets in Tanzania from 2012 to 2016. Image analysis software then helped the researchers compare the patterns within each pair according to 11 traits, including spot shape, size and color.
10-2-18 New hummingbird species spotted in Ecuador
A new species of hummingbird has been spotted and identified in Ecuador by a multinational team of ornithologists. The bird has been named Oreotrochilus cyanolaemus, or blue-throated hillstar, for its deep blue neck and is about 11cm (4in) long. Ecuador, which is rich in biodiversity, is home to 132 hummingbird species out of the more than 300 in the world. Ornithologists say there are only about 300 blue-throated hillstars and that the species is in danger of extinction. Francisco Sornoza is the ornithologist who led the team of researchers from Ecuador, Venezuela, Denmark and Sweden which made the discovery. He told Agence France Press news agency that he had a hunch it could be a hitherto unknown species as soon as he spotted it through binoculars in the barren south-western highlands of Ecuador. The area is historically poorly explored by ornithologists and the population of blue-throated hillstars is relatively small.
10-2-18 Baby giraffes with small and oval markings are most likely to die
Masai giraffes born with large or round spots may find it easier to hide from predators than giraffes with small or elliptical spots. With their long necks and yellow-brown patchy fur, giraffes may all look the same to us. But none of them have exactly the same coat markings – and certain patterns, especially those with large and rounder spots, can increase a baby giraffe’s chances of survival before they turn four months old. Biologists can’t decide what drove giraffes to evolve their patches. It is possible that the spots help giraffes regulate body temperature or identify each other. Some researchers believe that giraffe spots are for camouflage: before they grow into the tallest animal on earth, baby giraffes choose to hide from predators in the dappled shade of trees and bushes. Derek Lee at the Wild Nature Institute in New Hampshire and his colleagues are intrigued by the diverse coat patterns seen in populations of Masai giraffes, the world’s largest giraffe species. While some individuals have large and round spots, others have small and snowflake-shaped dots. The team identified 258 wild baby giraffes living in Northern Tanzania and recaptured them every two months for three years. They found calves that have fewer, and thus larger, spots had a 17 per cent higher chance of survival than those with a larger number of smaller spots. What’s more, those with more circular spots had a 27% higher survival rate than those with elliptical spots. Spot size and shape only influenced survival rate before calves turn four months old, which is the point at which they are large enough to be relatively safe from attack by predators like lions and hyenas.
10-1-18 Man's best friend, wildlife's worst enemy
They are our animal companions, first domesticated by humans as much as 50,000 years ago. But as the global population of domestic dogs continues to grow, are humans' canine companions posing a threat to wildlife? Science writer Dr Justyna Kulczyk-Malecka investigates. It took Dr Julie Young the better part of a winter to stop her dog - named ZZ Bottom - from chasing the local wild turkeys. "Squirrels are the hardest for him not to chase", she tells me. "But I train my dog, and I just tell him 'sit' or 'stay' and he will." It is very much in Dr Young's interest to make sure she has a perfectly-behaved canine. As well as loving the local hiking trails of her native Utah, she is a behavioural research ecologist with the US Department of Agriculture's National Wildlife Research Centre. Dr Young studies the impact of very badly-behaved dogs on local wildlife. The scientist's journey into this subject began a decade ago in Mongolia, where she studied the calves of endangered Mongolian saiga. "Saiga antelopes in Mongolia were already an endangered species, and what we have seen doing the field work was that feral and free-roaming dogs were sometimes harassing the saiga" she says. "They were running away from dogs and expending more energy, which is critical - especially during the calving season - because they might get separated from their young." As it turned out, the research worldwide shows similar results - free-roaming dogs occasionally attacking wildlife, which can threaten the conservation of endangered species. As the human population grows, so does the population of our companion animals, meaning dogs are roaming into territory that used to be a haven for wild animals. The numbers certainly back that up - there are now an estimated one billion domestic dogs around the world. "There's just going to be more conflict [of wildlife] with dogs," says Dr Young.