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By Joshua Sokol For half the year, a little brown bird on the northernmost islands of the Galápagos uses its wickedly sharp beak to pick at seeds, nectar and insects. But when the climate dries out, it drinks blood. Yes, there is such a thing as a vampire finch. Yes, it is what it sounds like. Galápagos finches have been used since Darwin’s time to illustrate evolution in action. Even among them, Geospiza septentrionalis is an outlier, one of the few birds in the world to intentionally draw and drink blood. And the species is only found on Wolf and Darwin islands, two of the most remote and off-limits places in the entire archipelago. The vampire finch has a method. First, one bird hops on the back of a resting Nazca booby, pecks at the base of the seabird’s wing, and drinks. Blood stains the booby’s white feathers. Other finches crowd around to wait their turn, or to watch and learn. Because adult boobies can fly away, the attacks are almost never fatal. The only casualties are chicks that flee from the finches on foot and, unable to find their way back, starve. Drinking blood is an unusual diet, and research published last year showed that vampire finches have evolved specialized bacteria in their guts to aid digestion. Even more surprising, according to a paper this week in the journal Philosophical Transactions of the Royal Society B, is that some of these bacteria are similar to ones found in the vampire bats of Central and South America. Se Jin Song, a biologist at the University of California San Diego and the study’s lead author, had previously studied the convergent evolution of gut bacteria. Do disparate animals with the equivalent of fad diets — eating only ants and termites, for instance — develop similar gut microbiota over evolutionary time? © 2019 The New York Times Company

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 26312 - Posted: 06.10.2019

Bruce Bower People and Neandertals separated from a common ancestor more than 800,000 years ago — much earlier than many researchers had thought. That conclusion, published online May 15 in Science Advances, stems from an analysis of early fossilized Neandertal teeth found at a Spanish site called Sima de los Huesos. During hominid evolution, tooth crowns changed in size and shape at a steady rate, says Aida Gómez-Robles, a paleoanthropologist at University College London. The Neandertal teeth, which date to around 430,000 years ago, could have evolved their distinctive shapes at a pace typical of other hominids only if Neandertals originated between 800,000 and 1.2 million years ago, she finds. Gómez-Robles’ study indicates that, if a common ancestor of present-day humans and Neandertals existed after around 1 million years ago, “there wasn’t enough time for Neandertal teeth to change at the rate [teeth] do in other parts of the human family tree” in order to end up looking like the Spanish finds, says palaeoanthropologist Bernard Wood of George Washington University in Washington, D.C. Many researchers have presumed that a species dubbed Homo heidelbergensis, thought to have inhabited Africa and Europe, originated around 700,000 years ago and gave rise to an ancestor of both Neandertals and Homo sapiens by roughly 400,000 years ago. Genetic evidence that Sima de los Huesos fossils came from Neandertals raised suspicions that a common ancestor with H. sapiens existed well before that (SN Online: 3/14/16). Recent Neandertal DNA studies place that common ancestor at between 550,000 and 765,000 years old. But those results rest on contested estimates of how fast and how consistently genetic changes accumulated over time. |© Society for Science & the Public 2000 - 2019.

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 26239 - Posted: 05.17.2019

By Cara Giaimo Here’s a pop quiz for you. Tom is taller than Dick. Dick is taller than Harry. Who’s taller, Harry or Tom? If you said Tom, congratulations! You just demonstrated what’s called “transitive inference” — the ability to compare things indirectly, based on previous juxtapositions. But before you pat yourself on the back too much, you should know that this skill was recently demonstrated by another creature: the humble paper wasp that might be living in your backyard right now. In the summer of 2017, researchers at the University of Michigan put two species of paper wasps through a transitive inference test. A statistically significant portion of the time, the wasps passed. Other animals — including rats, geese and cichlid fish — have also exhibited this capacity. But this study, which was published Tuesday in Biology Letters, is the first to successfully showcase it in an invertebrate (honeybees failed a similar test in 2004). Paper wasps are found on every continent except Antarctica. You might be near some right now. “They tend to nest in the eaves of houses, or inside barbecue grills,” said Elizabeth Tibbetts, the study’s lead author. In a previous study, Dr. Tibbetts showed that individual female wasps can identify one another by their distinct facial patterns, which resemble Rorschach ink blots. “When two wasps meet, they learn, ‘Oh, that’s what Suzy looks like,’” she said. “And the next time they meet, they remember who Suzy is.” In the spring, the females spend a lot of time brawling, getting in each other’s faces and trading slaps with their appendages. These matchups look like schoolyard tussles. “Some wasps will be fighting; some wasps will be watching the fights,” said Dr. Tibbetts. “It’s a very exciting time.” The wasps remember the winners and losers, and use them to establish a social hierarchy: the strongest reproduce, while the weaker ones do all the work. © 2019 The New York Times Company

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 26229 - Posted: 05.11.2019

Matthew Warren Scientists have uncovered the most complete remains yet from the mysterious ancient-hominin group known as the Denisovans. The jawbone, discovered high on the Tibetan Plateau and dated to more than 160,000 years ago, is also the first Denisovan specimen found outside the Siberian cave in which the hominin was uncovered a decade ago — confirming suspicions that Denisovans were more widespread than the fossil record currently suggests. The research marks the first time an ancient human has been identified solely through the analysis of proteins. With no usable DNA, scientists examined proteins in the specimen’s teeth, raising hopes that more fossils could be identified even when DNA is not preserved. “This is fantastic work,” says Katerina Douka, an archaeologist at the Max Planck Institute for the Science of Human History in Jena, Germany, who runs a separate project aiming to uncover Denisovan fossils in Asia. “It tells us that we are looking at the right area.” Until now, everything scientists have learnt about Denisovans has come from a handful of teeth and bone fragments from Denisova Cave in Russia’s Altai Mountains. DNA from these remains revealed that the Denisovans were a sister group to Neanderthals, both descending from a population that split away from modern humans about 550,00–765,000 years ago. And at Denisova Cave, the two groups seem to have met and interbred: a bone fragment described last year belonged an ancient-human hybrid individual who had a Denisovan father and Neanderthal mother.

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 26198 - Posted: 05.02.2019

By Sam Roberts Ralph Solecki, an archaeologist whose research helped debunk the view of Neanderthals as heartless and brutish half-wits and inspired a popular series of novels about prehistoric life, died on March 20 in Livingston, N.J. He was 101. The cause was pneumonia, his son William said. Starting in the mid-1950s, leading teams from Columbia University, Dr. Solecki discovered the fossilized skeletons of eight adult and two infant Neanderthals who had lived tens of thousands of years ago in what is now northern Iraq. Dr. Solecki, who was also a Smithsonian Institution anthropologist at the time, said physical evidence at Shanidar Cave, where the skeletons were found, suggested that Neanderthals had tended to the weak and the wounded, and that they had also buried their dead with flowers, which were placed ornamentally and possibly selected for their therapeutic benefits. The exhumed bones of a man, named Shanidar 3, who had been blind in one eye and missing his right arm but who had survived for years after he was hurt, indicated that fellow Neanderthals had helped provide him with sustenance and other support. “Although the body was archaic, the spirit was modern,” Dr. Solecki wrote in the magazine Science in 1975. Large amounts of pollen found in the soil at a grave site suggested that bodies might have been ceremonially entombed with bluebonnet, hollyhock, grape hyacinth and other flowers — a theory that is still being explored and amplified. (Some researchers hypothesized that the pollen might have been carried by rodents or bees, but Dr. Solecki’s theory has become widely accepted.) “The association of flowers with Neanderthals adds a whole new dimension to our knowledge of his humanness, indicating he had a ‘soul,’ ” Dr. Solecki wrote. © 2019 The New York Times Company

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 26131 - Posted: 04.12.2019

By Carl Zimmer In a cave in the Philippines, scientists have discovered a new branch of the human family tree. At least 50,000 years ago, an extinct human species lived on what is now the island of Luzon, researchers reported on Wednesday. It’s possible that Homo luzonensis, as they’re calling the species, stood less than three feet tall. The discovery adds growing complexity to the story of human evolution. It was not a simple march forward, as it once seemed. Instead, our lineage assumed an exuberant burst of strange forms along the way. Our species, Homo sapiens, now inhabits a comparatively lonely world. “The more fossils that people pull out of the ground, the more we realize that the variation that was present in the past far exceeds what we see in us today,” said Matthew Tocheri, a paleoanthropologist at Lakehead University in Canada, who was not involved in the new discovery. In the early 2000s, Armand Salvador Mijares, a graduate student at the University of the Philippines, was digging at Callao Cave, on Luzon, for traces of the first farmers on the Philippines. Soon, he decided to dig a little deeper. Researchers on the Indonesian island of Flores had discovered the bones of an extraordinary humanlike species about 60,000 years old. The scientists named it Homo floresiensis. Some features were similar to ours, but in other ways Homo floresiensis more closely resembled other hominins (the term scientists use for modern humans and other species in our lineage). © 2019 The New York Times Company

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 26126 - Posted: 04.11.2019

/ By Richard Kemeny Northern Ethiopia was once home to a vast, ancient lake. Saber-toothed cats prowled around it, giant crocodiles swam within. The streams and rivers that fed it — over 3 million years ago, during the Pliocene — left behind trails of sediment that have now hardened into sandstone. Deposited within these layers are fossils: some of early hominins, along with the bones of hippos, antelope, and elephants. Anthropologist Jessica Thompson encountered two of these specimens, from an area named Dikika, in 2010. At the time, she was a visiting researcher at the Institute of Human Origins at Arizona State University. Given no explanation as to their history, she analyzed the bones and found signs of butchery. Percussion marks suggested someone may have accessed the marrow; cut marks hinted that flesh was stripped from bone. To her surprise, the specimens were 3.4 million years old, putting the butcher’s behaviors back 800,000 years earlier than conventional estimates would suggest. That fact got Thompson, now an assistant professor in the Department of Anthropology at Yale University, thinking there might be more traces of tool use from those early times. In a wide-ranging review published in February’s issue of Current Anthropology, Thompson joins a team of researchers to weave together several strands of recent evidence and propose a new theory about the transition to large animal consumption by our ancestors. The prevailing view, supported by a confluence of fossil evidence from sites in Ethiopia, is that the emergence of flaked tool use and meat consumption led to the cerebral expansion that kickstarted human evolution more than 2 million years ago. Thompson and her colleagues disagree: Rather than using sharpened stones to hunt and scrape meat from animals, they suggest, earlier hominins may have first bashed bones to harvest fatty nutrients from marrow and brains. Copyright 2019 Undark

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 26107 - Posted: 04.03.2019

By Lee Dugatkin Like many breakthroughs in science, Dmitri Belyaev’s silver fox domestication experiment began with a thunderbolt: one simple, powerful, new idea. Born of a parish priest in early 20th century Russia, the geneticist proposed that all domestic animals were tamed through a generations-long process in which our distant ancestors repeatedly chose the calmest animals — those that were friendliest to people — for breeding. Whether horses for transport, dogs for protection, pigs for food, or oxen for labor, the essential trait was that the animals not try to bite the hand that fed them. Belyaev went on to speculate that all of the other characteristics we tend to see in domesticated species — their curly tails, floppy ears, juvenile facial, and body features — were somehow byproducts of this selection for the friendliest of the friendly. As a test, Belyaev decided that he would build a dog out of a fox, in real time, to understand how man’s best friend came to be. No one had ever attempted anything like it. No matter, he would try. At the time, in Stalinist Russia, the idea was considered radical and out of line with State orthodoxy. There were men who might very well have thrown the scientist in prison for what he was dreaming. But he would perform his magic in a far off, frozen land: The Siberian town of Novosibirsk, where winter temperatures can plummet to a bone-chilling -50 degrees Fahrenheit. Some 60 years later, his experiment is still going. It is one of the longest running science experiments ever, having outlived even its creator. And after all this time, it is still shaping the way we think about fundamental questions in biology — and even influencing the way we understand our own evolutionary trajectory. Copyright 2019 Undark

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 25940 - Posted: 02.08.2019

Ewen Callaway Neanderthals and Denisovans might have lived side by side for tens of thousands of years, scientists report in two papers in Nature1,2. The long-awaited studies are based on the analysis of bones, artefacts and sediments from Denisova Cave in southern Siberia, which is dotted with ancient-human remains. They provide the first detailed history of the site’s 300,000-year occupation by different groups of ancient humans. “We can now tell the whole story of the entire cave, not just bits and pieces,” says Zenobia Jacobs, a geochronologist at the University of Wollongong, Australia, who co-led one of the studies. Soviet archaeologists began unravelling the story of Denisova Cave, at the foot of the Altai Mountains, in the early 1980s. Since then, scientists have found the fragmentary remains of nearly a dozen ancient humans at the site. The cave became world famous in 2010, after an analysis of the DNA from a tiny hominin finger bone found that the creature was distinct from both modern humans and Neanderthals3. It belonged to a previously unknown hominin group, later named Denisovans. Additional sequencing of the DNA in bone remains from the cave found that Denisovans were a sister group to Neanderthals, and might once have lived across Asia — where they interbred with the ancestors of some humans now living there4. © 2019 Springer Nature Publishing AG

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 25916 - Posted: 01.31.2019

By Elizabeth Pennisi TAMPA, FLORIDA—Swimming through the oceans, voraciously consuming plankton and other small creatures—and occasionally startling a swimmer—the beautiful gelatinous masses known as comb jellies won’t be joining Mensa anytime soon. But these fragile creatures have nerve cells—and they offer insights about the evolutionary origins of all nervous systems, including our own. Inspired by studies of a glue-secreting cell unique to these plankton predators, researchers have now proposed that neurons emerged in the last common ancestor of today’s animals—and that their progenitors were secretory cells, whose primary function was to release chemicals into the environment. Joseph Ryan, a computational evolutionary biologist the University of Florida Whitney Laboratory for Marine Bioscience in St. Augustine, suggested that scenario last year after tracing the development of nerve cells in embryos of comb jellies, among the most ancient animals. Earlier this week at the annual meeting of the Society for Integrative and Comparative Biology (SICB) here, he marshaled evidence from developmental studies of other animals, all pointing to common origins for some neuron and secretory cells. “What Ryan is proposing is novel and important,” says David Plachetzki, an evolutionary biologist at the University of New Hampshire in Durham. Among other mysteries, it could resolve a long debate about whether the nervous system evolved twice early in animal life. © 2018 American Association for the Advancement of Science

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 25857 - Posted: 01.11.2019

Bruce Bower An ancient hominid skeleton dubbed Little Foot possessed a brain largely similar to that of modern chimpanzees and an inner ear with a mix of apelike and humanlike features, two studies suggest. These findings, along with other analyses of the adult female’s 3.67-million-year-old skeleton, point to the piecemeal evolution of humanlike traits in close relatives of our species, scientists say. The research is part of the first formal analyses of Little Foot’s skeleton, which was discovered more than 20 years ago in a South African cave but was recently removed from its rocky encasing. Other analyses of trunk and limb bones indicate that Little Foot, who lived perhaps a million years before the emergence of the human genus, Homo, already walked upright about as well as people today do (SN: 1/19/19, p.13). Although Little Foot consists of a nearly complete skeleton, her evolutionary identity is controversial. Paleoanthropologist Ronald Clarke of the University of the Witwatersrand in Johannesburg — Little Foot’s discoverer and a coauthor of the two new studies — assigns the find to Australopithecus prometheus, an early extinct hominid species that many scientists don’t regard as valid. Other researchers regard Little Foot as an early member of Australopithecus africanus, a species previously known from fossils discovered at several South African sites (SN: 1/19/19, p. 13). |© Society for Science & the Public 2000 - 2018

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 25855 - Posted: 01.10.2019

Ewen Callaway No human has the brain of a Neanderthal — but some have hints of its shape. The brain shape of some people with European ancestry is influenced by Neanderthal DNA acquired through interbreeding tens of thousands of years ago, researchers report on 13 December in Current Biology1. These DNA variants seem to affect the expression of two genes in such a way as to make the brains of some humans slightly less round, and more like the Neanderthals’ elongated brains. “It’s a really subtle shift in the overall roundedness,” says team member Philipp Gunz, a palaeoanthropologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “I don’t think you would see it with your naked eye. These are not people that would look Neanderthal-like.” The Neanderthal DNA variants alter gene expression in brain regions involved in planning, coordination and learning of movements. These faculties are used in speech and language, but there is no indication that the Neanderthal DNA affects cognition in modern humans. Instead, the researchers say, their discovery points to biological changes that might have endowed the human brain with its distinct shape. Earlier this year, Gunz and two colleagues determined that the rounded brain shape of modern humans evolved gradually, reaching its current appearance between 35,000 and 100,000 years ago2. The earliest human fossils from across Africa, dating to around 200,000–300,000 years ago, have large yet elongated brains. “There really is something going on in the brain that changes over time in the Homo sapiens lineage,” says Gunz. © 2018 Springer Nature Publishing AG

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 25787 - Posted: 12.15.2018

Bruce Bower A nearly complete hominid skeleton known as Little Foot has finally been largely freed from the stony shell in which it was discovered in a South African cave more than 20 years ago. And in the first formal analyses of the fossils, researchers say the 3.67-million-year-old Little Foot belonged to its own species. In four papers posted online at bioRxiv.org between November 29 and December 5, paleoanthropologist Ronald Clarke of the University of the Witwatersrand in Johannesburg and colleagues assign Little Foot to a previously proposed species, Australopithecus prometheus, that has failed to gain traction among many researchers. Clarke has held that controversial view for more than a decade (SN: 5/2/15, p. 8). He found the first of Little Foot’s remains in a storage box of fossils from a site called Sterkfontein in 1994. Excavations of the rest of the skeleton began in 1997. Many other researchers, however, regard Little Foot as an early member of a hominid species called Australopithecus africanus. Anthropologist Raymond Dart first identified A. africanus in 1924 from an ancient youngster’s skull called the Taung Child. Hundreds of A. africanus fossils have since been found in South African caves, including Sterkfontein. One of those caves, Makapansgat, produced a partial braincase that Dart assigned to A. prometheus in 1948. But Dart dropped that label after 1955, assigning the braincase and another Makapansgat fossil to A. africanus. |© Society for Science & the Public 2000 - 2018.

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 25778 - Posted: 12.12.2018

One of the animals that's thought to give creatures like apes, dolphins and crows a run for their money when it comes to intelligence is the octopus. For those other animals, there's a pattern to how they evolved to be so smart — they live long, socially complex lives. But that's not the case for octopuses that live solitary lives for the year or two they usually survive. Now scientists think they've figured out how the octopus became so so smart, and it has to do with the loss of their shell through evolution. "Octopuses, unlike many other molluscs, they do not have a protective shell," said Piero Amodio, the lead author on the new study published in the journal Trends in Ecology & Evolution about how cephalopods (octopuses and their relatives) gained their intelligence. "So [octopuses] are very, very vulnerable to many kinds of predators — from fishes to marine mammals to birds — and the idea is that by becoming quite smart, this is a kind of weapon they can use to avoid being eaten." Amodio, a PhD student at the University of Cambridge, told Quirks & Quarks host Bob McDonald that this evolutionary process differs from those that led to intelligence in other groups of vertebrates. Intelligence in other vertebrates is thought to have arisen because they live long and socially complex lives. Building a brain is a metabolically labour intensive process, so it's a big investment for an animal to develop a big brain like in apes, dolphins, and crows — an investment they get a return on when they live a long time. ©2018 CBC/Radio-Canada.

Related chapters from BN8e: Chapter 17: Learning and Memory; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 25763 - Posted: 12.08.2018

Bruce Bower Neandertals are shaking off their reputation as head bangers. Our close evolutionary cousins experienced plenty of head injuries, but no more so than late Stone Age humans did, a study suggests. Rates of fractures and other bone damage in a large sample of Neandertal and ancient Homo sapiens skulls roughly match rates previously reported for human foragers and farmers who have lived within the past 10,000 years, concludes a team led by paleoanthropologist Katerina Harvati of the University of Tübingen in Germany. Males suffered the bulk of harmful head knocks, whether they were Neandertals or ancient humans, the scientists report online November 14 in Nature. “Our results suggest that Neandertal lifestyles were not more dangerous than those of early modern Europeans,” Harvati says. Until recently, researchers depicted Neandertals, who inhabited Europe and Asia between around 400,000 and 40,000 years ago, as especially prone to head injuries. Serious damage to small numbers of Neandertal skulls fueled a view that these hominids led dangerous lives. Proposed causes of Neandertal noggin wounds have included fighting, attacks by cave bears and other carnivores and close-range hunting of large prey animals. Paleoanthropologist Erik Trinkaus of Washington University in St. Louis coauthored an influential 1995 paper arguing that Neandertals incurred an unusually large number of head and upper-body injuries. Trinkaus recanted that conclusion in 2012, though. All sorts of causes, including accidents and fossilization, could have resulted in Neandertal skull damage observed in relatively small fossil samples, he contended (SN: 5/27/17, p. 13). |© Society for Science & the Public 2000 - 2018.

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 25686 - Posted: 11.15.2018

By Virginia Morell When wild orangutans spot a predator, they let out a loud “kiss-squeak,” a call that sounds like a human smooching. That noise tells tigers and other enemies, “I’ve seen you,” scientists believe, and it also lets other orangutans know danger is near. Now, researchers report having heard orangutans making this call long after predators have passed—the first evidence that primates other than humans can “talk” about the past. “The results are quite surprising,” says Carel van Schaik, a primatologist at the University of Zurich in Switzerland who was not involved in the work. The ability to talk about the past or the future “is one of the things that makes language so effective,” he says. That suggests, he adds, that the new findings could provide clues to the evolution of language itself. Many mammals and birds have alarm calls, some of which include information on the type and size of a predator, its location and distance, and what level of danger it poses. But until now, researchers have never heard wild animals announcing danger after the fact. Adriano Reis e Lameira, a postdoctoral student at the University of St. Andrews in the United Kingdom, was examining alarm calls in orangutans in Sumatra’s dense Ketambe forest, where the primates have been observed for nearly 40 years. He set up a simple experiment to investigate their alarm calls: A scientist draped in a tiger-striped, spotted, or plain sheet walked on all fours along the forest floor, right underneath lone female orangutans sitting in trees at heights of 5 to 20 meters above the ground. © 2018 American Association for the Advancement of Science

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 25685 - Posted: 11.15.2018

By Neil Genzlinger Dorothy L. Cheney, whose careful research into how primates live and communicate revealed the surprising complexity of their thought processes and social structures, died on Friday at her home in Devon, Pa. She was 68. Her husband and research partner, Robert M. Seyfarth, said the cause was breast cancer. “Cheney was a spectacular scientist,” Robert M. Sapolsky, a professor of biology and neurology at Stanford University and the author of books like “A Primate’s Memoir,” said by email. “Along with Robert Seyfarth, she did wonderfully clever, elegant field experiments that revealed how other primates think about the world — showing that they think in far more sophisticated and interesting ways than people anticipated.” Rather than doing their research in laboratories, Dr. Cheney and Dr. Seyfarth spent long stretches in the wilds of Africa and elsewhere, studying gorillas, baboons, vervet monkeys and other animals. One of their best-known experiments, conducted in Kenya in 1977, showed that vervets made distress sounds not just involuntarily, out of fear, but to convey a specific message about a given threat. They hid loudspeakers in bushes, played recorded sounds of vervets and watched the reaction. A particular bark sent the animals scurrying up trees because it was a warning about leopards; a low-pitched staccato noise had them looking skyward for predatory eagles. They summarized their research in their first book, “How Monkeys See the World: Inside the Mind of Another Species” (1990). Later research in Botswana included insights into the hierarchical nature of baboon societies and its possible evolutionary effects. “Because Western scientists learned about primates by examining corpses or observing single animals brought home as pets,” they wrote in their 2007 book, “Baboon Metaphysics: The Evolution of a Social Mind,” “few if any ever learned what can be discovered only through long, patient observation: that the most human features of monkeys and apes lie not in their physical appearance but in their social relationships.” © 2018 The New York Times Company

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex
Link ID: 25683 - Posted: 11.15.2018

David Sington Aubrey Manning’s hugely popular 1998 BBC series Earth Story, about the evolution and shaping of the planet Earth, inspired a generation and led to a noticeable increase in students applying to read earth sciences. Yet, Aubrey, who has died aged 88, was not a geologist, but an ethologist, whose work made an important contribution to the understanding of how animal behaviour plays a role in the evolution of new species. In a series of experiments at Oxford and Edinburgh universities – he was professor of natural history (1973-97) at the latter – Aubrey showed how mutations in genes that affect the behaviour of fruit flies could lead to reproductive isolation, a key mechanism in the creation of new species. This work laid the foundation for the modern study of the evolutionary genetics of behaviour. His 1967 publication An Introduction to Animal Behaviour, now in its sixth edition, is still the standard textbook in its field, and his lectures were so popular – packed with students from many other courses – that the university took to scheduling them for 9am on Mondays as the most effective way to get undergraduates out of bed. It was this reputation as a superb communicator of science that led the BBC to his door. When as its producer I approached him in 1997 to present Earth Story, Aubrey, with typical modesty, protested that I had the wrong man and insisted on introducing me to his geological colleagues. However, it was the very fact that the subject was new to him that was the secret of the ventures success. © 2018 Guardian News and Media Limited

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:None
Link ID: 25667 - Posted: 11.12.2018

By Carl Zimmer People of Asian and European descent — almost anyone with origins outside of Africa — have inherited a sliver of DNA from some unusual ancestors: the Neanderthals. These genes are the result of repeated interbreeding long ago between Neanderthals and modern humans. But why are those genes still there 40,000 years after Neanderthals became extinct? As it turns out, some of them may protect humans against infections. In a study published on Thursday, scientists reported new evidence that modern humans encountered new viruses — including some related to influenza, herpes and H.I.V. — as they expanded out of Africa roughly 70,000 years ago. Some of those infections may have been picked up directly from Neanderthals. Without immunity to pathogens they had never encountered, modern humans were particularly vulnerable. “We were actually able to not only say, ‘Yes, modern humans and Neanderthals exchanged viruses,’” said David Enard, an evolutionary biologist at the University of Arizona and co-author of the new paper, published in the journal Cell. “We are able to start saying something about which types of viruses were involved.” But if Neanderthals made us sick, they also helped keep us well. Some of the genes inherited from them through interbreeding also protected our ancestors from these infections, just as they protected the Neanderthals. Lluis Quintana-Murci, a geneticist at the Pasteur Institute in Paris who was not involved in the new research, said that until now, scientists had not dreamed of getting such a glimpse at the distant medical history of our species. “Five years ago, we would never have imagined that,” he said. © 2018 The New York Times Company

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 25533 - Posted: 10.05.2018

By JoAnna Klein Plants have no eyes, no ears, no mouth and no hands. They do not have a brain or a nervous system. Muscles? Forget them. They’re stuck where they started, soaking up the sun and sucking up nutrients from the soil. And yet, when something comes around to eat them, they sense it. And they fight back. How is this possible? “You’ve got to think like a vegetable now,” says Simon Gilroy, a botanist who studies how plants sense and respond to their environments at the University of Wisconsin-Madison. “Plants are not green animals,” Dr. Gilroy says. “Plants are different, but sometimes they’re remarkably similar to how animals operate.” To reveal the secret workings of a plant’s threat communication system for a study published Thursday in Science, Masatsugu Toyota (now a professor at Saitama University in Japan) and other researchers in Dr. Gilroy’s lab sent in munching caterpillars like in the video above. They also slashed leaves with scissors. They applied glutamate, an important neurotransmitter that helps neurons communicate in animals. In these and about a dozen other videos, they used a glowing, green protein to trace calcium and accompanying chemical and electrical messages in the plant. And they watched beneath a microscope as warnings transited through the leafy green appendages, revealing that plants aren’t as passive as they seem. The messages start at the point of attack, where glutamate initiates a wave of calcium that propagates through the plant’s veins, or plumbing system. The deluge turns on stress hormones and genetic switches that open plant arsenals and prepare the plant to ward off attackers — with no thought or movement. © 2018 The New York Times Company

Related chapters from BN8e: Chapter 6: Evolution of the Brain and Behavior; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 25450 - Posted: 09.14.2018