Chapter 6. Evolution of the Brain and Behavior

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Ian Sample Science editor Fossils recovered from an old mine on a desolate mountain in Morocco have rocked one of the most enduring foundations of the human story: that Homo sapiens arose in a cradle of humankind in East Africa 200,000 years ago. Archaeologists unearthed the bones of at least five people at Jebel Irhoud, a former barite mine 100km west of Marrakesh, in excavations that lasted years. They knew the remains were old, but were stunned when dating tests revealed that a tooth and stone tools found with the bones were about 300,000 years old. Why we're closer than ever to a timeline for human evolution Read more “My reaction was a big ‘wow’,” said Jean-Jacques Hublin, a senior scientist on the team at the Max Planck Institute for Evolutionary Anthropology in Leipzig. “I was expecting them to be old, but not that old.” Hublin said the extreme age of the bones makes them the oldest known specimens of modern humans and poses a major challenge to the idea that the earliest members of our species evolved in a “Garden of Eden” in East Africa one hundred thousand years later. “This gives us a completely different picture of the evolution of our species. It goes much further back in time, but also the very process of evolution is different to what we thought,” Hublin told the Guardian. “It looks like our species was already present probably all over Africa by 300,000 years ago. If there was a Garden of Eden, it might have been the size of the continent.” © 2017 Guardian News and Media Limited

Keyword: Evolution
Link ID: 23723 - Posted: 06.08.2017

By Katie Langin No one likes a con artist. People avoid dealing with characters who have swindled them in the past, and—according to new research—birds avoid those people, too. Ravens, known more for their intelligence, but only slightly less for their love of cheese, were trained by researchers to trade a crust of bread for a morsel of cheese with human partners. When the birds then tried to broker a trade with “fair” and “unfair” partners—some completed the trade as expected, but others took the raven’s bread and kept (and ate) the cheese—the ravens avoided the tricksters in separate trials a month later. This suggests that ravens can not only differentiate between “fair” and “unfair” individuals, but they retain that ability for at least a month, the researchers write this month in Animal Behavior. Ravens have a complex social life involving friendships and rivalries. Their ability to recognize and punish dishonest individuals, even after a single encounter, may help explain how cooperation evolved in this group of birds. For people, though, the moral of the story is simple: Be nice to ravens. © 2017 American Association for the Advancement of Science.

Keyword: Intelligence; Evolution
Link ID: 23709 - Posted: 06.06.2017

By EMILIE LE BEAU LUCCHESI Benjamin Stepp, an Iraq war veteran, sat in his graduate school course trying to focus on the lecture. Neither his classmates nor his professor knew he was silently seething. But his service dog, Arleigh, did. She sensed his agitation and “put herself in my lap,” said Mr. Stepp, 37, of Holly Springs, Miss. “I realized I needed to get out of class. We went outside, I calmed down. We breathed.” During his two deployments to Iraq, Mr. Stepp endured a traumatic brain injury and multiple surgeries on his ankle, and most days he suffers excruciating pain in his legs and lower back. He says he also returned from the war with a lot of anger, which wells up at unexpected times. “Anger kept us alive overseas,” Mr. Stepp said. “You learn that anger keeps you alive.” Now that he is back, though, that anger no longer serves a useful purpose. And Arleigh, a lab and retriever mix who came to Mr. Stepp from K9s For Warriors, a nonprofit organization that trains service dogs, has been helping him to manage it. The dog senses when his agitation and anxiety begin rising, and sends him signals to begin the controlled breathing and other exercises that help to calm him down. Pet owners and trainers have long been aware of a dog’s ability to sense a human’s emotions. In the last 10 years, researchers, too, have begun to explore more deeply the web of emotions, both positive and negative, that can spread between people and animals, said Natalia Albuquerque, an ethologist who studies animal cognition at the University of São Paulo in Brazil and the University of Lincoln in England. The spread of emotions between animals and people, or between animals — what researchers refer to as emotional contagion — is an emerging field of science. But “there are still many unanswered questions we need to address,” Ms. Albuquerque said. © 2017 The New York Times Company

Keyword: Emotions; Evolution
Link ID: 23708 - Posted: 06.05.2017

By Julie Hecht I have been scaring dog lovers for nearly a decade, and Tamas Farago—lead researcher behind a new study on dog growls and cross-species communication—is mostly to blame. I met Farago in 2010 when visiting his research group—the Family Dog Project at Eotvos Lorand University—to conduct my Masters research. By then, Farago was already immersed in the study of dog vocalizations—particularly their barks and growls—so when my study concluded and it was time to leave Budapest, I departed with not only a deep appreciation for paprika and palinka, but also a few audio clips of dogs growling, courtesy of Farago. Since then, whenever I give a talk about canine science, audience members are sure to chuckle, their faces brightening, as recordings of a dog’s breathy, garbled, fast-paced, play growls take over the room. But when I play the low, elongated aggressive growls corresponding to a dog being approached by a threatening stranger or a dog guarding food, even my hair will often stand up. These growls mean business. If a dog happens to be attending the talk—not that I hold lectures for dogs, but if a human brought their dog—I take note before playing the growls. This is because a 2010 study by Farago and colleagues found that dogs not only listen to growls, but extract meaningful information from them. Here’s how they figured this out: In the study, dogs entered a room where they came across a bone. Fine. Normal so far. Just a bone sitting all alone. But unbeknownst to the dogs, a speaker was concealed in a covered crate sitting just behind the bone, and as the dogs approached, one of three growls was played from the speaker (food guarding, threatening stranger, or play). Excellent work sneaky researchers! © 2017 Scientific American

Keyword: Animal Communication; Language
Link ID: 23672 - Posted: 05.29.2017

By STEPH YIN A female and male get together. One thing leads to another, and they have sex. His sperm fuses with her egg, half of his DNA combining with half of her DNA to form an embryo. As humans, this is how we tend to think of reproduction. But there are many other bizarre ways reproduction can take place. For instance, scientists have discovered a fish carrying genes only from its father in the nucleus of its cells. Found in a type of fish called Squalius alburnoides, which normally inhabits rivers in Portugal or Spain, this is the first documented instance in vertebrates of a father producing a near clone of itself through sexual reproduction — a rare phenomenon called androgenesis — the researchers reported in the journal Royal Society Open Science on Wednesday. The possibility of androgenesis is just one of many mysteries about Squalius alburnoides. It’s not a species in the usual sense, but rather something called a hybrid complex, a group of organisms with multiple parental combinations that can mate with one another. The group is thought to have arisen from hybridization between females of one species, Squalius pyrenaicus, and males of another species, now extinct, that belonged to a group of fish called Anaecypris. To sustain its population, Squalius alburnoides mates with several other closely related species belonging to the Squalius lineage. That it can reproduce at all is unusual enough. Most hybrids, like mules, are sterile because the chromosomes from their parents of different species have trouble combining, swapping DNA and dividing — steps required for egg or sperm production. Squalius alburnoides males circumvent this problem by producing sperm cells that do not divide, and therefore contain more than one chromosome set. This is important because most animals, Squalius alburnoides included, need at least two chromosome sets to survive. © 2017 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 23669 - Posted: 05.27.2017

By Virginia Morell Baby marmosets learn to make their calls by trying to repeat their parents’ vocalizations, scientists report today in Current Biology. Humans were thought to be the only primate with vocal learning—the ability to hear a sound and repeat it, considered essential for speech. When our infants babble, they make apparently random sounds, which adults respond to with words or other sounds; the more this happens, the faster the baby learns to talk. To find out whether marmosets (Callithrix jacchus, pictured) do something similar, scientists played recordings of parental calls during a daily 30-minute session to three sets of newborn marmoset twins until they were 2 months old (roughly equivalent to a 2-year-old human). Baby marmosets make noisy guttural cries; adults respond with soft “phee” contact calls (listen to their calls below). The baby that consistently heard its parents respond to its cries learned to make the adult “phee” sound much faster than did its twin, the team found. It’s not yet known if this ability is limited to the marmosets; if so, the difference may be due to the highly social lives of these animals, where, like us, multiple relatives help care for babies. © 2017 American Association for the Advancement of Science

Keyword: Language; Animal Communication
Link ID: 23662 - Posted: 05.26.2017

James Gorman Darwin’s finches, those little birds in the Galápagos with beaks of different sizes and shapes, were instrumental in the development of the theory of evolution. Similar birds had large and small beaks and beaks in between, all related to what kinds of insects and seeds they ate. From one ancestor, it seemed, different adaptations to the environment had evolved, giving the birds that adapted a survival edge in a particular ecological niche — evolution by natural selection. Biologists who came later went on to identify the genetic changes that had produced different beak shapes. Now another group of finch-like birds has provided a similar example, but of a different kind of evolution, one driven not by the demands of the environment, but by the demands of female birds. Their preferences in color and pattern caused the evolution of different species of seedeater, all with the same behavior and diet, but with males that look different. That’s a process called sexual selection, which Darwin also wrote about. Leonardo Campagna, a researcher at Cornell University and the Cornell Lab of Ornithology, and a group of scientists from the United States and South America investigated nine species of southern capuchino seedeaters, doing full genomes for each one and reported their findings in Science Advances. They found that the DNA of all the species is remarkably similar, as are the birds. All the females look alike and all of the species feed on grass seeds plucked from grass stalks of living plants. Only the males are different. They have a wide variety of colorations and their courting songs are also distinct. Dr. Campagna and the other researchers found that differences between species DNA were all minimal, ranging from as little as 0.03 percent to as great as 0.3 percent. All the species showed variation in the same area, DNA that appeared to have a role in regulating genes for the pigment melanin. © 2017 The New York Times Company

Keyword: Evolution; Sexual Behavior
Link ID: 23660 - Posted: 05.25.2017

Tina Hesman Saey Face-to-face, a human and a chimpanzee are easy to tell apart. The two species share a common primate ancestor, but over millions of years, their characteristics have morphed into easily distinguishable features. Chimps developed prominent brow ridges, flat noses, low-crowned heads and protruding muzzles. Human noses jut from relatively flat faces under high-domed crowns. Those facial features diverged with the help of genetic parasites, mobile bits of genetic material that insert themselves into their hosts’ DNA. These parasites go by many names, including “jumping genes,” “transposable elements” and “transposons.” Some are relics of former viruses assimilated into a host’s genome, or genetic instruction book. Others are self-perpetuating pieces of genetic material whose origins are shrouded in the mists of time. “Transposable elements have been with us since the beginning of evolution. Bacteria have transposable elements,” says evolutionary biologist Josefa González. She doesn’t think of transposons as foreign DNA. They are parts of our genomes — like genes. “You cannot understand the genome without understanding what transposable elements are doing,” says González, of the Institute of Evolutionary Biology in Barcelona. She studies how jumping genes have influenced fruit fly evolution. Genomes of most organisms are littered with the carcasses of transposons, says Cédric Feschotte, an evolutionary geneticist at the University of Utah in Salt Lake City. Fossils of the DNA parasites build up like the remains of ancient algae that formed the white cliffs of Dover. One strain of maize, the organism in which Nobel laureate Barbara McClintock first discovered transposable elements in the 1940s, is nearly 85 percent transposable elements (SN: 12/19/09, p. 9). Corn is an extreme example, but humans have plenty, too: Transposable elements make up nearly half of the human genome. |© Society for Science & the Public 2000 - 2017

Keyword: Development of the Brain; Genes & Behavior
Link ID: 23627 - Posted: 05.17.2017

By FERRIS JABR Con Slobodchikoff and I approached the mountain meadow slowly, obliquely, softening our footfalls and conversing in whispers. It didn’t make much difference. Once we were within 50 feet of the clearing’s edge, the alarm sounded: short, shrill notes in rapid sequence, like rounds of sonic bullets. We had just trespassed on a prairie-dog colony. A North American analogue to Africa’s meerkat, the prairie dog is trepidation incarnate. It lives in subterranean societies of neighboring burrows, surfacing to forage during the day and rarely venturing more than a few hundred feet from the center of town. The moment it detects a hawk, coyote, human or any other threat, it cries out to alert the cohort and takes appropriate evasive action. A prairie dog’s voice has about as much acoustic appeal as a chew toy. French explorers called the rodents petits chiens because they thought they sounded like incessantly yippy versions of their pets back home. On this searing summer morning, Slobodchikoff had taken us to a tract of well-trodden wilderness on the grounds of the Museum of Northern Arizona in Flagstaff. Distressed squeaks flew from the grass, but the vegetation itself remained still; most of the prairie dogs had retreated underground. We continued along a dirt path bisecting the meadow, startling a prairie dog that was peering out of a burrow to our immediate right. It chirped at us a few times, then stared silently. “Hello,” Slobodchikoff said, stooping a bit. A stout bald man with a scraggly white beard and wine-dark lips, Slobodchikoff speaks with a gentler and more lilting voice than you might expect. “Hi, guy. What do you think? Are we worth calling about? Hmm?” Slobodchikoff, an emeritus professor of biology at Northern Arizona University, has been analyzing the sounds of prairie dogs for more than 30 years. Not long after he started, he learned that prairie dogs had distinct alarm calls for different predators. Around the same time, separate researchers found that a few other species had similar vocabularies of danger. What Slobodchikoff claimed to discover in the following decades, however, was extraordinary: Beyond identifying the type of predator, prairie-dog calls also specified its size, shape, color and speed; the animals could even combine the structural elements of their calls in novel ways to describe something they had never seen before. No scientist had ever put forward such a thorough guide to the native tongue of a wild species or discovered one so intricate. Prairie-dog communication is so complex, Slobodchikoff says — so expressive and rich in information — that it constitutes nothing less than language.

Keyword: Language; Evolution
Link ID: 23606 - Posted: 05.12.2017

Shelby Putt How did humans get to be so smart, and when did this happen? To untangle this question, we need to know more about the intelligence of our human ancestors who lived 1.8 million years ago. It was at this point in time that a new type of stone tool hit the scene and the human brain nearly doubled in size. Some researchers have suggested that this more advanced technology, coupled with a bigger brain, implies a higher degree of intelligence and perhaps even the first signs of language. But all that remains from these ancient humans are fossils and stone tools. Without access to a time machine, it’s difficult to know just what cognitive features these early humans possessed, or if they were capable of language. Difficult – but not impossible. Now, thanks to cutting-edge brain imaging technology, my interdisciplinary research team is learning just how intelligent our early tool-making ancestors were. By scanning the brains of modern humans today as they make the same kinds of tools that our very distant ancestors did, we are zeroing in on what kind of brainpower is necessary to complete these tool-making tasks. The stone tools that have survived in the archaeological record can tell us something about the intelligence of the people who made them. Even our earliest human ancestors were no dummies; there is evidence for stone tools as early as 3.3 million years ago, though they were probably making tools from perishable items even earlier. © 2010–2017, The Conversation US, Inc.

Keyword: Evolution; Brain imaging
Link ID: 23594 - Posted: 05.09.2017

Bruce Bower Fossils of a humanlike species with some puzzlingly ancient skeletal quirks are surprisingly young, its discoverers say. It now appears that this hominid, dubbed Homo naledi, inhabited southern Africa close to 300,000 years ago, around the dawn of Homo sapiens. H. naledi achieved worldwide acclaim in 2015 as a possibly pivotal player in the evolution of the human genus, Homo. Retrieved from an underground chamber in South Africa, fossils of this species were thought to be anywhere from 900,000 to at least 1.8 million years old (SN: 8/6/16, p. 12). A younger age for H. naledi resolves one mystery about these cave fossils. It doesn’t, however, answer questions about how long ago the species first appeared and when it died out. What is now known is that H. naledi bodies somehow ended up in Dinaledi Chamber, part of South Africa’s Rising Star cave system, between 236,000 and 335,000 years ago, an international team reports in one of three papers published May 9 in eLife. Paleoanthropologist Lee Berger of the University of the Witwatersrand in Johannesburg headed the team. Geoscientist Paul Dirks of James Cook University in Townsville, Australia, directed the dating effort. In the first paper, two methods of measuring the concentration of natural uranium and other radioactive elements, and damage caused by those elements over time, provided key age estimates for three H. naledi teeth. A thin sheet of rock deposited by flowing water just above the fossils was also dated. |© Society for Science & the Public 2000 - 201

Keyword: Evolution
Link ID: 23591 - Posted: 05.09.2017

By RICHARD O. PRUM In a mossy forest in the western Andes of Ecuador, a small, cocoa-brown bird with a red crown sings from a slim perch. Bip-Bip-WANNGG! It sounds like feedback from an elfin electric guitar. Three rival birds call back in rapid response. These male club-winged manakins are showing off to attract female mates. Their strange songs are associated with an even stranger movement. Instead of opening their beaks, they flick their wings open at their sides to make the Bips, and then snap their wings up over their backs to produce the extraordinary WANNGG. They are singing with their wings, and their potential mates seem to find the sound very alluring. This is an evolutionary innovation — a whole new way to sing. But the evolutionary mechanism behind this novelty is not adaptation by natural selection, in which only those who survive pass on their genes, allowing the species to become better adapted to its environment over time. Rather, it is sexual selection by mate choice, in which individuals pass on their genes only if they’re chosen as mates. From the peacock’s tail to the haunting melodies of the wood thrush, mate choice is responsible for much of the beauty in the natural world. Most biologists believe that these mechanisms always work in concert — that sex appeal is the sign of an objectively better mate, one with better genes or in better condition. But the wing songs of the club-winged manakin provide new insights that contradict this conventional wisdom. Instead of ensuring that organisms are on an inexorable path to self-improvement, mate choice can drive a species into what I call maladaptive decadence — a decline in survival and fecundity of the entire species. It may even lead to extinction. © 2017 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 23580 - Posted: 05.06.2017

By Sam Wong Six years ago, a chimpanzee had the bright idea to use moss to soak up water, then drink from it, and seven others soon learned the trick. Three years later, researchers returned to the site to see if the practice had persisted to become part of the local chimp culture. They now report that the technique has continued to spread, and it’s mostly been learned by relatives of the original moss-spongers. This adds to earlier evidence that family ties are the most important routes for culture to spread in animals. After the first report of chimps using moss as a sponge in Budongo Forest, Uganda, researchers rarely saw the behaviour again, and wondered whether chimps still knew how to do it. So they set up an experiment, providing moss and leaves at the clay pit where the chimps had demonstrated the technique before. Then they watched to see whether chimpanzees would use leaves – a more common behaviour – or moss to soak up the mineral-rich water from the pit. The eight original moss-spongers all used moss again during the experiment, and so did another 15 chimps, showing the practice had become more widespread. The researchers wondered what factors influenced which individuals adopted it: were they connected socially, or through families, for instance? © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Evolution
Link ID: 23543 - Posted: 04.27.2017

Bruce Bower NEW ORLEANS — A relatively small brain can pack a big evolutionary punch. Consider Homo naledi, a famously puzzling fossil species in the human genus. Despite having a brain only slightly larger than a chimpanzee’s, H. naledi displays key humanlike neural features, two anthropologists reported April 20 at the annual meeting of the American Association of Physical Anthropologists. Those brain characteristics include a region corresponding to Broca’s area, which spans parts of the right and left sides of the brain in present-day people. The left side is typically involved in speech and language. “It looks like Homo naledi’s brain evolved a huge amount of shape change that supported social emotions and advanced communication of some type,” said Shawn Hurst of Indiana University Bloomington, who presented the new findings. “We can’t say for sure whether that included language.” Frontal brain locations near Broca’s area contribute to social emotions such as empathy, pride and shame. As interactions within groups became more complex in ancient Homo species, neural capacities for experiencing social emotions and communicating verbally blossomed, Hurst suspects. Scientists don’t know how long ago H. naledi inhabited Africa’s southern tip. If H. naledi lived 2 million or even 900,000 years ago, as some researchers have suggested (SN: 8/6/16, p. 12), humanlike brains with a language-related area would be shocking. A capacity for language is thought to have emerged in Homo over the last few hundred thousand years at most. |© Society for Science & the Public 2000 - 2017.

Keyword: Evolution
Link ID: 23541 - Posted: 04.26.2017

By Virginia Morell Humpback whales are known for their operatic songs that carry across the seas. Their calves, however, whisper, uttering soft squeaks and grunts to their mothers (which you can hear above). Now, a new study suggests that loud calf voices can also attract some unwanted visitors: male humpbacks, who might separate the pair by trying to mate with the mother, and killer whales, who dine on young humpbacks. To record their sounds, scientists placed temporary tagging devices on eight humpback whale mothers and calves in the Exmouth Gulf off Western Australia, where the young whales spend months suckling to gain enough weight for their annual migrations to the Antarctic or Arctic. After listening to the recordings, scientists say the calves’ careful whispers are not cries for food, as previously thought. Instead, they may help them stay in close contact with their mothers when swimming. And, say researchers, writing today in Functional Ecology, the low decibel sounds help keep would-be predators away from the “nursery.” © 2017 American Association for the Advancement of Science

Keyword: Animal Communication
Link ID: 23534 - Posted: 04.26.2017

Amber Dance Biologist Leo Smith held an unusual job while an undergraduate student in San Diego. Twice a year, he tagged along on a chartered boat with elderly passengers. The group needed him to identify two particular species of rockfish, the chilipepper rockfish and the California shortspine thornyhead. Once he’d found the red-orange creatures, the passengers would stab themselves in the arms with the fishes’ spines. Doing so, the seniors believed, would relieve their aching arthritic joints. Smith, now at the University of Kansas in Lawrence, didn’t think much of the practice at the time, but now he wonders if those passengers were on to something. Though there’s no evidence that anything in rockfish venom can alleviate pain — most fish stings are, in fact, quite painful themselves — some scientists suspect fish venom is worth a look. Studying the way venom molecules from diverse fishes inflict pain might help researchers understand how nerve cells sense pain and lead to novel ways to dull the sensation. Smith is one of a handful of scientists who are studying fish venoms, and there’s plenty to investigate. An estimated 7 to 9 percent of fishes, close to 3,000 species, are venomous, Smith’s work suggests. Venomous fishes are found in freshwater and saltwater, including some stingrays, catfishes and stonefishes. Some, such as certain fang blennies, are favorites in home aquariums. Yet stinging fishes haven’t gotten the same attention from scientists as snakes and other venomous creatures. |© Society for Science & the Public 2000 - 2017

Keyword: Pain & Touch; Neurotoxins
Link ID: 23515 - Posted: 04.20.2017

By Elizabeth Pennisi By standing on the shoulders of giants, humans have built the sophisticated high-tech world we live in today. Tapping into the knowledge of previous generations—and those around us—was long thought to be a “humans-only” trait. But homing pigeons can also build collective knowledge banks, behavioral biologists have discovered, at least when it comes to finding their way back to the roost. Like humans, the birds work together and pass on information that lets them get better and better at solving problems. “It is a really exciting development in this field,” says Christine Caldwell, a psychologist at the University of Stirling in the United Kingdom who was not involved with the work. Researchers have admired pigeon intelligence for decades. Previous work has shown the birds are capable of everything from symbolic communication to rudimentary math. They also use a wide range of cues to find their way home, including smell, sight, sound, and magnetism. On its own, a pigeon released multiple times from the same place will even modify its navigation over time for a more optimal route home. The birds also learn specific routes from one another. Because flocks of pigeons tend to take more direct flights home than individuals, scientists have long thought some sort of “collective intelligence” is at work. © 2017 American Association for the Advancement of Science

Keyword: Animal Migration; Evolution
Link ID: 23504 - Posted: 04.18.2017

By Niall Firth The firing of every neuron in an animal’s body has been recorded, live. The breakthrough in imaging the nervous system of a hydra – a tiny, transparent creature related to jellyfish – as it twitches and moves has provided insights into how such simple animals control their behaviour. Similar techniques might one day help us get a deeper understanding of how our own brains work. “This could be important not just for the human brain but for neuroscience in general,” says Rafael Yuste at Columbia University in New York City. Instead of a brain, hydra have the most basic nervous system in nature, a nerve net in which neurons spread throughout its body. Even so, researchers still know almost nothing about how the hydra’s few thousand neurons interact to create behaviour. To find out, Yuste and colleague Christophe Dupre genetically modified hydra so that their neurons glowed in the presence of calcium. Since calcium ions rise in concentration when neurons are active and fire a signal, Yuste and Dupre were able to relate behaviour to activity in glowing circuits of neurons. For example, a circuit that seems to be involved in digestion in the hydra’s stomach-like cavity became active whenever the animal opened its mouth to feed. This circuit may be an ancestor of our gut nervous system, the pair suggest. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging; Evolution
Link ID: 23483 - Posted: 04.12.2017

Nicola Davis Apes are on a par with human infants in being able to tell when people have an accurate belief about a situation or are actually mistaken, researchers say. While previous work has shown that great apes understand the goals, desires and perceptions of others, scientists say the latest finding reveals an important cognitive ability. “For the last 30 or more years people thought that belief understanding is the key marker of humans and really differentiates us from other species – and this does not seem to be the case,” said David Buttelmann, co-author of the research from the Max Planck Institute for Evolutionary Anthropology in Germany. Apes can guess what others are thinking - just like humans, study finds Read more The results follow on the heels of a study published last year which also suggests that apes understand the concept of false beliefs – after research that used eye-tracking technology to monitor the gaze of apes exposed to various pranks carried out by an actor dressed in a King Kong suit. But the new study, says Buttelmann, is an important step forward, showing that apes not only understand false belief in others, but apply that understanding to their own actions. Writing in the journal Plos One, Buttelmann and colleagues described exploring the understanding of false belief in 34 great apes, including bonobos, chimpanzees and orangutans, using a test that can be passed by human infants at one to two years of age. © 2017 Guardian News and Media Limited

Keyword: Attention; Consciousness
Link ID: 23457 - Posted: 04.06.2017

Elle Hunt Inches above the seafloor of Sydney’s Cabbage Tree Bay, with the proximity made possible by several millimetres of neoprene and a scuba diving tank, I’m just about eyeball to eyeball with this creature: an Australian giant cuttlefish. Even allowing for the magnifying effects of the mask snug across my nose, it must be about 60cm (two feet) long, and the peculiarities that abound in the cephalopod family, that includes octopuses and squid, are the more striking writ so large. ADVERTISING Its body – shaped around an internal surfboard-like shell, tailing off into a fistful of tentacles – has the shifting colour of velvet in light, and its W-shaped pupils lend it a stern expression. I don’t think I’m imagining some recognition on its part. The question is, of what? It was an encounter like this one – “at exactly the same place, actually, to the foot” – that first prompted Peter Godfrey-Smith to think about these most other of minds. An Australian academic philosopher, he’d recently been appointed a professor at Harvard. While snorkelling on a visit home to Sydney in about 2007, he came across a giant cuttlefish. The experience had a profound effect on him, establishing an unlikely framework for his own study of philosophy, first at Harvard and then the City University of New York. The cuttlefish hadn’t been afraid – it had seemed as curious about him as he was about it. But to imagine cephalopods’ experience of the world as some iteration of our own may sell them short, given the many millions of years of separation between us – nearly twice as many as with humans and any other vertebrate (mammal, bird or fish)

Keyword: Evolution; Learning & Memory
Link ID: 23429 - Posted: 03.30.2017