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By Michelle Clement I like video games (I will rip up some Assassin’s Creed whenever I get a long weekend, do NOT get me started). My cat likes video games too, even though she doesn’t understand that she’s playing them. On a whim not too long ago, I downloaded a “games for cats” app on my iPad that simulates a dancing laser pointer or a skittering mouse, and my cat gets so into the game that she’ll push my iPad all the way across the floor in her excitement. Here’s a video of someone else’s kitten playing the same game: The phenomenon isn’t restricted to domesticated cats, either: Cats aren’t the only animals that are mentally stimulated by flashing and dancing lights, though. As it turns out, researchers at Wageningen University, in the course of their research on ethical livestock farming, noticed that pigs like to play with dancing lights as well. European regulations currently require that pig farmers provide mentally-stimulating activity for their pigs in order to reduce boredom, which leads to aggression and biting, and researchers at Wageningen University, in collaboration with the Utrecht School of the Arts, are currently developing a video game called “Pig Chase” for livestock pigs that is not unlike my cat’s iPad app. The key difference, however, is that this game would be an interspecies two-player game. [EDIT: I was contacted this afternoon by Nate at Hiccup, and he informed me that Game For Cats has also recently incorporated interspecies functionality. I didn't know that, so thanks for the update!] © 2012 Scientific American,

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 0: ; Chapter 14: Attention and Consciousness
Link ID: 16235 - Posted: 01.10.2012

by Jeff Hecht Tortoises aren’t noted for their speed but they are surprisingly quick-witted "IT ALL stems from Moses," says Anna Wilkinson. Moses is her pet red-footed tortoise and a bit of a celebrity in the science world. Why? First, he outsmarted rats in a maze. Then he was the inspiration for a new lab studying reptile intelligence and the evolutionary origins of cognition. Now he has helped Wilkinson win an Ig Nobel prize. Victory for slow and steady. This fruitful partnership began in 2004, after Wilkinson, now at the University of Lincoln, UK, started graduate school at the University of York, also in the UK. She was studying bird cognition but had earlier become fascinated by tortoises while employed in education and research at Flamingo Land zoo in North Yorkshire, UK. Although working with primates, she found herself drawn to the tortoise enclosure. Even when most of the group was basking in the sun, she recalls, at least one tortoise was exploring or feeding, and when a person walked in they all perked up, sensing that food was likely to follow. "They were always just fascinating," she says. So, a tortoise was the obvious choice as a pet. Moses's first big academic break came in 2006. Wilkinson was attending a lecture on how rats remember their paths through a maze, when she started thinking: "Moses can do that." Afterwards, she asked the lecturer, Geoffrey Hall, if anyone had tried putting tortoises in such mazes. A literature search indicated that reptiles in general have proved pretty dim when subjected to cognitive tests. Undeterred, Hall and Wilkinson decided to see what Moses was capable of. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: 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: 16193 - Posted: 12.27.2011

by Jeff Warren What if we merged brains with other species? Would we have very different psychology? Or wordlessly swap intimate feelings? I'VE spent years thinking about consciousness and my current obsession is whether we can know anything about what it is like is to be a dog, a dolphin, or a bat. The most influential answer came from philosopher Thomas Nagel in his 1974 paper, "What is it like to be a bat?" Unlike some of the era's behaviourists, who saw animals as little more than automatons that respond to stimulus, Nagel didn't doubt bats had experience, that it was "like something" being a nimble, echo-locating mammal swooping through the night. But he doubted our ability to say anything true about it beyond projection or imagination. Nagel may be right, but for me the human-to-animal mind question is simply an extreme form of the human-to-human mind question: we can't know another's experience, but there are deep points of overlap we can expand. What follows is from a conversation with two of the smartest people I know in the field: Lori Marino, a comparative neuroanatomist at Emory University in Atlanta, Georgia, and Ben Goertzel, a mathematician, and a former research director of the Singularity Institute for Artificial Intelligence in San Francisco. JEFF: Imagine that in front of us are the disarticulated brains of a human, a dog and a dolphin. What might we learn by combining the pieces of the animals in unusual ways? LORI: Something similar is going on in Leipzig. For example, researchers inserted a human gene into a mouse brain, causing it to grow human-like neurons in the language area: the mouse's vocalisations were deeper. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 0: ; Chapter 14: Attention and Consciousness
Link ID: 16191 - Posted: 12.27.2011

By Susan Milius Pigeons, who aren’t even distant uncles to a monkey, have matched primates in a test of learning an abstract numerical concept. Trained on one-two-three, the pigeons then had to put pairs of numbers up to nine in order, says comparative psychologist Damian Scarf of the University of Otago in New Zealand. Pigeons rivaled rhesus monkeys tested earlier at the same task, Scarf and his colleagues report in the Dec. 23 Science. The results “suggest that despite completely different brain organization and hundreds of millions of years of evolutionary divergence, pigeons and monkeys solve this problem in a similar way,” says Elizabeth Brannon of Duke University, a coauthor of the original study of numerical order in monkeys. Humankind may be pretty proud of its numerical prowess, but numbers — four succulent fruits versus eight, one lurking lion versus three — matter very much in animal life, too. Research is uncovering various kinds of number-related abilities in animals as diverse as the honeybee, mosquitofish, grey parrot, Plethodon salamanders and a waterbird called a coot. So pigeons could be compared with other species, Scarf used Brannon’s numerical-order test, which baboons and lemurs as well as some monkeys have passed. For training, pigeons saw computer screens displaying sets of three images, each with one, two or three shapes. The shapes varied so that a bird couldn’t get the number order right just by pecking at increasing surface area. Scarf then rewarded birds for pecking in one-shape, two-shapes, three-shapes order. © Society for Science & the Public 2000 - 2011

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 0: ; Chapter 14: Attention and Consciousness
Link ID: 16178 - Posted: 12.23.2011

by Peter Aldhous Itsy bitsy spiders have a big problem: where to store their bulging brains. For Anapisona simoni and other arachnid lightweights, the problem is so acute that their brains have literally spilled out of their body cavities and into their legs. Tiny creatures' brains and microelectronics have something in common, it turns out: ultimately, attempts to miniaturise the circuitry will hit a wall. Once the axons that transmit neural signals get down to 0.1 micrometre in diameter, for instance, channels that move ions across cell membranes get so "noisy" that signalling becomes unreliable. What's more, nervous tissue demands a lot of energy, and if nerve cells get too small they simply don't contain enough mitochondria – organelles that act as cellular power plants – to meet their needs. As a result, animals face a trade-off as natural selection pushes them towards the minuscule: either dumb down, or lug around brains that are much bigger, proportionate to body size, than those needed by a larger creatures with similar smarts. Weaving websMovie Camera is not for dullards, so tiny spiders haven't taken the evolutionary road to stupidity. In 2007, William Eberhard of the Smithsonian Tropical Research Institute in Panama and the University of Costa Rica found that the smallest spiders weave webs that are just as complex as those made by larger relatives. "There was no correlation between the size of the spider and the precision with which it built the sticky spiral in the web," he says. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 16150 - Posted: 12.15.2011

By Bruce Bower Culturally speaking, ancient East Africans were a stone’s throw away from southern Arabia. Stone tools collected at several sites along a plateau in Oman, which date to roughly 106,000 years ago, match elongated cutting implements previously found at East African sites from around the same time, say archaeologist Jeffrey Rose of the University of Birmingham, England, and his colleagues. New finds also include cores — or rocks from which tools were pounded off with a hammer stone — that correspond to East African specimens, the researchers report online November 30 in PLoS ONE. East African sites that have yielded these distinctive stone artifacts extend southward along the Nile River to the Horn of Africa. “In the mountain of papers speculating about human dispersal out of Africa, a link between southern Arabia and the Nile Valley has never been considered,” Rose says. Either Africans crossed the Red Sea and trekked into southern Arabia well before an African exodus around 60,000 years ago, or ancient people from Arabia influenced African toolmaking, the scientists suggest. “The finds in Oman are rather spectacular,” comments archaeologist Michael Petraglia of the University of Oxford, England. “They have a date that is earlier than similar African artifacts, which could imply a migration back to Africa, or at least a flow between African and Arabian populations.” © Society for Science & the Public 2000 - 2011

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 16141 - Posted: 12.13.2011

by Rowan Hooper WHAT was the basis for the earliest friendships? If wild chimps are any guide: support in a fight, borrowing a valued tool, and a bite to eat now and then. Quite similar to our friendships today, in fact. Indeed, some chimps are so modern they have relationships that we would classify as friends with benefits. Primatologists are reassessing the complexity of chimpanzee society in the light of new findings that also suggest answers to a long-standing question: why share things with non-relatives? For the first time wild chimps in Senegal have been observed taking plant foods and tools from other chimps, who don't react to the intrusion. The chimps donating their stuff don't get paid, but neither do they protest. Instead, the trade appears to help build social cohesion. What's more, in another west African study, this time in Ivory Coast, a "market" has been described where chimps exchange commodities in the shape of both social behaviours including grooming and sex, and resources such as meat. Christophe Boesch of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, says we have only recently begun to appreciate the time and energy chimps invest in reciprocal relationships, and he compares chimp relationships to friendship. "These findings have prompted primatologists to use some terms that have in the past been reserved for humans." © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 0: ; Chapter 11: Emotions, Aggression, and Stress
Link ID: 16119 - Posted: 12.08.2011

Clive Gamble Wondering what went on in the heads of Neanderthals has rarely produced positive thoughts. H. G. Wells set the bar low in his short story The Grisly Folk in 1921, writing: “We cannot conceive in our different minds the strange ideas that chased one another through those queerly shaped brains.” Wells's hatchet job was effective. Other authors have offered sympathetic alternatives, such as Isaac Asimov's 1958 short story The Ugly Little Boy. But the idea of a 'thinking Neanderthal' has become an evolutionary oxymoron on a par with 'military intelligence' and 'airline food'. Yet cognition certainly took place in the Neanderthal brain — the largest in human evolution, housed in a long, distinctively shaped skull. In How to Think Like a Neandertal, archaeologist Thomas Wynn and psychologist Frederick Coolidge provide one of the most rounded portraits yet of a fossil human. The book covers familiar areas — diet, symbolism and language — but also includes innovative assessments of Neanderthals' capacity to tell jokes, and even speculations on what they might have dreamed about. The authors use the Neanderthals as a means of discussing the evolutionary reasons for such cognitive abilities as humour and deception. We have learned much about Neanderthals in the past 150 years. They were powerfully built and top carnivores. Their stone tools are found across Eurasia. We know from their genome sequence that the last common ancestor of Neanderthals and ourselves lived some half a million years ago. They became extinct in southern Spain as recently as 30,000 years ago. © 2011 Nature Publishing Group,

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 16065 - Posted: 11.22.2011

When the Society for Neuroscience gets together for their annual meeting each year, a city of scientists suddenly forms for a week. This year’s meeting has drawn 31,000 people to the Washington DC Convention Center. The subjects of their presentations ranged from brain scans of memories to the molecular details of disorders such as Parkinson’s and autism. This morning, a scientist named Svante Paabo delivered a talk. Its subject might make you think that he had stumbled into the wrong conference altogether. He delivered a lecture about Neanderthals. Yet Paabo did not speak to an empty room. He stood before thousands of researchers in the main hall of the convention center. His face was projected onto a dozen giant screens, as if he were opening for the Rolling Stones. When Paabo was done, the audience released a surging crest of applause. One neuroscientist I know, who was sitting somewhere in that huge room, sent me a one-word email as Paabo finished: “Amazing.” You may well know about Paabo’s work. In August, Elizabeth Kolbert published a long profile in the New Yorker. But he’s been in the news for fifteen years. I’ve also followed his work since the mid-1990s, having written about pieces of Paabo’s work in newspapers, magazines, and books. But it was bracing to hear him bring together the scope of his research in an hour–including new experiments that Paabo’s colleagues are presenting at the meeting. He has changed the way scientists study human evolution. Along with fossils, they can now study genomes that belonged to people who died 40,000 years ago. They can do experiments to see how some of those individual genes helped to make us human. During his talk, Paabo used this new research to sketch out a sweeping vision of how our ancestors evolved uniquely human brains as they swept out across the world. © 2011, Kalmbach Publishing Co.

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 16042 - Posted: 11.17.2011

By Nick Bascom Primates may have evolved from living the lonely life to forming complex societies in two major steps, a new study of more than 200 species suggests. Understanding when and why the ancestors of Homo sapiens and its closest cousins adopted different social structures could help reveal more about the evolution of human society. About 52 million years ago, primates — an order of animals that includes, among others, humans and great apes — might have stopped foraging alone and banded together in large, loosely formed, same-sex groups to search for food, anthropologist Susanne Shultz of the University of Oxford and colleagues report in the Nov. 10 Nature. Then around 16 million years ago, primates began forming more stable social groups, such as male-female pairs and harems dominated by one male, the researchers suggest. Teaming up this way may have been prompted by a switch from a nocturnal lifestyle to moving about in the sunshine. “Being active during the day would have allowed primates to travel across larger spaces and exploit their environment more effectively, but it would have also exposed them to a huge predation risk,” says Shultz. To make it through the day, primates would have needed a new defense strategy to deal with both a greater number of predators and also new kinds of hunters. “What’s going to nail you at night is different than what’s going to nail you during the day,” says primatologist Anthony Di Fiore of the University of Texas at Austin, who was not involved in the study. © Society for Science & the Public 2000 - 2011

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 16013 - Posted: 11.11.2011

by Helen Fields Hopping around in the Peruvian jungle, near the border with Brazil, is a menagerie of tiny poison dart frogs. Their wealth of colors and patterns—some have golden heads atop white-swirled bodies, others wear full-torso tattoos of black and neon-yellow stripes—act as the world's worst advertisement to predators: Don't eat me, I'm toxic. But why have so many designs evolved when a single one might do? Evolutionary biologist Mathieu Chouteau of the University of Montreal in Canada ventured into the rainforest to find out. He was on the trail of Ranitomeya imitator, a single species of poison dart frog that comes in about 10 different patterns. That variability should be confusing for predators, he says, because the warnings are supposed to be a message to them, and it would make more sense to give them only one design to keep track of. To figure out what was going on, Chouteau enlisted his girlfriend's help to make 3600 models of frogs, each 18 millimeters long. "It was, like, at least a month of working full-time," he says. They pressed black clay into frog-shaped molds and painted each one in one of two patterns: yellow striped or reticulated, like a giraffe, with green lines. They also made brown frogs as a nontoxic-looking control. Then Chouteau packed the frogs in his carryon baggage and flew to Peru. The models represent the frogs that live in two different sites: one in the Amazonian lowland and one in a valley at about 500 meters above sea level. The two sites are separated by a high ridge. In one very long day at each site, Chouteau set out 900 of the frogs on leaves along narrow trails used by locals to hunt in the forest. For the next 3 days, he went back and checked them to see whether the soft clay recorded evidence of attacks by birds. © 2010 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 0: ; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 15986 - Posted: 11.05.2011

By Tina Hesman Saey MONTREAL — Bigger, better human brains may be the result of a double dose of a gene that helps brain cells move around. At least twice in the past 3 million years, a gene called SRGAP2 has been duplicated within the human genome, says Megan Dennis of the University of Washington in Seattle. Dennis and her colleagues have now shown that extra copies of this gene may account for humans’ thicker brain cortex, the brain’s gray matter where thinking takes place. The team had previously discovered that SRGAP2 is one of 23 genes duplicated in humans but not in other primates. Dennis found that an ancient form of the gene, which is located on human chromosome 1, was partially duplicated on the same chromosome about 3.4 million years ago. That partial copy makes a shortened version of the SRGAP2 protein. Then, about 2.4 million years ago, a copy of the partial copy was created and added to the short arm of chromosome 1, Dennis reported October 13 at the International Congress of Human Genetics. But just having extra copies doesn’t mean the gene is evolutionarily important. So Dennis and her colleagues examined the duplicate genes in more than 150 people and found that the copy made 3.4 million years ago is missing in some people. But the younger version of the gene has become fixed in the human population, meaning that absolutely everyone has it. Millions of years may seem like a long time, but it is actually quite speedy for fixing duplicated genes, Dennis says. The rapid assimilation could indicate that the gene is important in human evolution. © Society for Science & the Public 2000 - 2011

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 0: ; Chapter 13: Memory, Learning, and Development
Link ID: 15913 - Posted: 10.15.2011

By Eric Michael Johnson Charles Darwin had more in common with chimpanzees than even he realized. Before he was universally known for his theory of natural selection, the young naturalist made a decision that has long been hailed as the type of behavior that fundamentally separates humans from other apes. In 1858, before Darwin published On the Origin of Species, his friend Alfred Russel Wallace​ mailed Darwin his own theory of evolution that closely matched what Darwin had secretly been working on for more than two decades. Instead of racing to publish and ignoring Wallace’s work, Darwin included Wallace’s outline alongside his own abstract so that the two could be presented jointly before the Linnean Society the following month. “I would far rather burn my whole book than that [Wallace] or any man should think that I had behaved in a paltry spirit,” Darwin wrote. This kind of prosocial behavior, a form of altruism that seeks to benefit others and promote cooperation, has now been found in chimps, the species that Darwin did more than any other human to connect us with. (This month's Science Agenda, about medical testing in chimps, notes other similarities that have been documented in chimps and humans.) In the study, published in the Proceedings of the National Academy of Sciences USA, primatologist Frans de Waal and his colleagues at the Yerkes National Primate Research Center at Emory University presented chimps with a simplified version of the choice that Darwin faced. Pairs of chimps were brought into a testing room where they were separated only by a wire mesh. On one side was a bucket containing 30 tokens that the chimpanzee could give to an experimenter for a food reward. Half of the tokens were of one color that resulted in only the chimpanzee that gave the token receiving a reward. The other tokens were of a different color that resulted in both chimpanzees receiving a food reward. If chimpanzees were motivated only by selfish interests, they would be expected to choose a reward only for themselves (or it should be 50–50 if they were choosing randomly). But individuals were significantly more likely to choose the prosocial outcome compared with the no-partner control. © 2011 Scientific American,

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 0: ; Chapter 11: Emotions, Aggression, and Stress
Link ID: 15868 - Posted: 10.04.2011

Our brains followed a twisting path of development through creatures that swam, crawled and walked the Earth long before we did. Here are a few of these animals, and how they helped make us what we are. Our single-celled ancestors had sophisticated machinery for sensing and responding to the environment. Once the first multicellular animals arose, this machinery was adapted for cell-to-cell communication. Specialised cells that could carry messages using electrical impulses and chemical signals – the first nerve cells – arose very early on. The first neurons were probably connected in a diffuse network across the body of a creature like this hydra. This kind of structure, known as a nerve net, can still be seen in the quivering bodies of jellyfish and sea anemones

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 15851 - Posted: 09.29.2011

by David Robson IT IS 30,000 years ago. A man enters a narrow cave in what is now the south of France. By the flickering light of a tallow lamp, he eases his way through to the furthest chamber. On one of the stone overhangs, he sketches in charcoal a picture of the head of a bison looming above a woman's naked body. In 1933, Pablo Picasso creates a strikingly similar image, called Minotaur Assaulting Girl. That two artists, separated by 30 millennia, should produce such similar work seems astonishing. But perhaps we shouldn't be too surprised. Anatomically at least, our brains differ little from those of the people who painted the walls of the Chauvet cave all those years ago. Their art, part of the "creative explosion" of that time, is further evidence that they had brains just like ours. How did we acquire our beautiful brains? How did the savage struggle for survival produce such an extraordinary object? This is a difficult question to answer, not least because brains do not fossilise. Thanks to the latest technologies, though, we can now trace the brain's evolution in unprecedented detail, from a time before the very first nerve cells right up to the age of cave art and cubism. The story of the brain begins in the ancient oceans, long before the first animals appeared. The single-celled organisms that swam or crawled in them may not have had brains, but they did have sophisticated ways of sensing and responding to their environment. "These mechanisms are maintained right through to the evolution of mammals," says Seth Grant at the Wellcome Trust Sanger Institute in Cambridge, UK. "That's a very deep ancestry." © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 15839 - Posted: 09.27.2011

by Ferris Jabr Slimy and often sluggish they may be, but some molluscs deserve credit for their brains – which, it now appears, they managed to evolve independently, four times. The mollusc family includes the most intelligent invertebrates on the planet: octopuses, squid and cuttlefishMovie Camera. Now, the latest and most sophisticated genetic analysis of their evolutionary history overturns our previous understanding of how they got so brainy. The new findings expand a growing body of evidence that in very different groups of animals – molluscs and mammals, for instance – central nervous systems evolved not once, but several times, in parallel. Kevin Kocot of Auburn University, Alabama, and his colleagues are responsible for the new evolutionary history of the mollusc family, which includes 100,000 living species in eight lineages. They analysed genetic sequences common to all molluscs and looked for differences that have accumulated over time: the more a shared sequence differs between two species, the less related they are. The findings, which rely on advanced statistical analyses, fundamentally rearrange branches on the mollusc family tree. In the traditional tree, snails and slugs (gastropods) are most closely related to octopuses, squid, cuttlefish and nautiluses (cephalopods), which appears to make sense in terms of their nervous systems: both groups have highly centralised nervous systems compared with other molluscs and invertebrates. Snails and slugs have clusters of ganglia – bundles of nerve cells – which, in many species, are fused into a single organ; cephalopods have highly developed central nervous systems that enable them to navigate a maze, use tools, mimic other species, learn from each other and solve complex problems. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 1: Biological Psychology: Scope and Outlook
Related chapters from MM:Chapter 0: ; Chapter 1: An Introduction to Brain and Behavior
Link ID: 15812 - Posted: 09.17.2011

by Alison George He has already revealed that early humans interbred with Neanderthals and discovered a whole new type of hominin from its DNA alone. Now Svante Pääbo is setting his sights on even more exotic discoveries. He tells Alison George why he thinks the bombshells will keep coming Last year you revealed a previously unknown type of hominin, called the Denisovans, from DNA in a pinkie bone found in a cave in Denisova, Siberia. Tell me about this. We knew people had lived in this cave, but thought they were either Neanderthals or modern humans. When we sequenced the DNA, I was in the US so a postdoc called me to tell me the results. He said: "Are you sitting down?" because it was immediately clear this was some other form of human; not a Neanderthal, not a modern human. We were totally shocked. This is the first time that a new form of human has been defined totally from molecular data, not from the morphology of fossils. I think this will happen much more in the future - that just from a tiny speck of bone we can determine the whole genome and reconstruct much of the history. You recently visited this cave. What was it like? The cave is in the Altai mountains in central Asia and it was the first time I had seen it. It is really beautiful. It's big, almost cathedral-like with light coming in through a natural chimney. And you know that in this cave there have been both the Denisovans and modern humans and perhaps Neanderthals too. I went there for a meeting where anatomists, palaeontologists and archaeologists came together for the first time to try to sort out what we can say about this group of humans. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 15770 - Posted: 09.06.2011

by Michael Marshall WHEN wondering about the origins of our brain, don't look to Homo sapiens, chimpanzees, fish or even wormsMovie Camera. Many key components first appeared in single-celled organisms, long before animals, brains and even nerve cells existed. Dirk Fasshauer of the University of Lausanne, Switzerland, and colleagues were studying a pair of essential neural proteins called Munc18/syntaxin1 when they decided to look for them in very simple, single-celled organisms. Choanoflagellates are aquatic organisms found in oceans and rivers around the globe. Being a single cell, they do not have nerves, yet the team found both proteins in the choanoflagellate Monosiga brevicollis, and the interaction between the two was the same as in neurons (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1106189108). These proteins are found in every nerve cell and control the release of the chemicals which neurons use to talk to each other, called neurotransmitters. The finding is intriguing on its own, but much more significant when combined with a growing body of evidence that essential brain components evolved in choanoflagellates before multicellular life appeared. In 2008, Xinjiang Cai of Duke University in Durham, North Carolina, discovered that M. brevicollis has the same calcium channels in its cells as those used by neurons (Molecular Biology and Evolution, DOI: 10.1093/molbev/msn077). Then, in 2010, it emerged that M. brevicollis also has several proteins that neurons use to process signals from their neighbours (BMC Evolutionary Biology, DOI: 10.1186/1471-2148-10-34). © Copyright Reed Business Information Ltd

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 15757 - Posted: 09.03.2011

Matt Kaplan The discovery of stone axes in the same sediment layer as cruder tools indicates that hominins with differing tool-making technologies may have coexisted. The axes, found in Kenya by Christopher Lepre, a palaeontologist at Columbia University in New York, and his team are estimated to be around 1.76 million years old. That's 350,000 years older than any other complex tools yet discovered. The finding, described today in Nature1, includes another important discovery: the hand axes, usually associated with the emergence around 1.5 million years ago of Homo erectus as the dominant hominin species, were found alongside primitive chopping tools that had already been in use for at least a million years. "This supports the idea that the two earliest stone-tool manufacturing techniques and traditions were, at least sometimes, utilized contemporaneously," says palaeoanthropologist Briana Pobiner at the Smithsonian Institution in Washington DC. Chip off the old block The hand axes, which have a distinctive, carefully made oval shape, are part of the Acheulian technology — those tools thought to have been developed around 1.6 million years ago. The more primitive tools, typically chunks of stone with crudely-chipped edges, belong to the earlier Oldowan toolkit. Because H. erectus is often associated with Acheulian tools, Lepre and his colleagues suggest that the hand axes they found might have been made by H. erectus, and the Oldowan tools by the less cognitively-capable Homo habilis. © 2011 Nature Publishing Group,

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 0:
Link ID: 15752 - Posted: 09.01.2011

By Matt McGrath Science reporter, BBC World Service Sexual relations between ancient humans and their evolutionary cousins are critical for our modern immune systems, researchers report in Science journal. Mating with Neanderthals and another ancient group called Denisovans introduced genes that help us cope with viruses to this day, they conclude. Previous research had indicated that prehistoric interbreeding led to up to 4% of the modern human genome. The new work identifies stretches of DNA derived from our distant relatives. In the human immune system, the HLA (human leucocyte antigen) family of genes plays an important role in defending against foreign invaders such as viruses. The authors say that the origins of some HLA class 1 genes are proof that our ancient relatives interbred with Neanderthals and Denisovans for a period. At least one variety of HLA gene occurs frequently in present day populations from West Asia, but is rare in Africans. The researchers say that is because after ancient humans left Africa some 65,000 years ago, they started breeding with their more primitive relations in Europe, while those who stayed in Africa did not. BBC © 2011

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 0: ; Chapter 11: Emotions, Aggression, and Stress
Link ID: 15727 - Posted: 08.27.2011