Ants are cool but teach us nothing

E.O. Wilson writes: For nearly seven decades, starting in boyhood, I’ve studied hundreds of kinds of ants around the world, and this qualifies me, I believe, to offer some advice on ways their lives can be applied to ours. I’ll start with the question I’m most often asked: “What can I do about the ants in my kitchen?” My response comes from the heart: Watch your step, be careful of little lives. Ants especially like honey, tuna and cookie crumbs. So put down bits of those on the floor, and watch as the first scout finds the bait and reports back to her colony by laying an odor trail. Then, as a little column follows her out to the food, you will see social behavior so strange it might be on another planet. Think of kitchen ants not as pests or bugs, but as your personal guest superorganism.

Another question I hear a lot is, “What can we learn of moral value from the ants?” Here again I will answer definitively: nothing. Nothing at all can be learned from ants that our species should even consider imitating. For one thing, all working ants are female. Males are bred and appear in the nest only once a year, and then only briefly. They are pitiful creatures with wings, huge eyes, small brains and genitalia that make up a large portion of their rear body segment. They have only one function in life: to inseminate the virgin queens during the nuptial season. They are built to be robot flying sexual missiles. Upon mating or doing their best to mate, they are programmed to die within hours, usually as victims of predators.

Many kinds of ants eat their dead — and their injured, too. You may have seen ant workers retrieve nestmates that you have mangled or killed underfoot (accidentally, I hope), thinking it battlefield heroism. The purpose, alas, is more sinister. [Continue reading...]

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How ancient DNA is rewriting human history

Michael White writes: There are no written records of the most important developments in our history: the transition from hunting and gathering to farming, the initial colonization of regions outside Africa, and, most crucially, the appearance of modern humans and the vanishing of archaic ones. Our primary information sources about these “pre-historic” events are ancient tools, weapons, bones, and, more recently, DNA. Like an ancient text that has picked up interpolations over the millennia, our genetic history can be difficult to recover from the DNA of people alive today. But with the invention of methods to read DNA taken from ancient bones, we now have access to much older copies of our genetic history, and it’s radically changing how we understand our deep past. What seemed like an episode of Lost turns out to be much more like Game of Thrones: instead of a story of small, isolated groups that colonized distant new territory, human history is a story of ancient populations that migrated and mixed all over the world.

There is no question that most human evolutionary history took place in Africa. But by one million years ago—long before modern humans evolved — archaic human species were already living throughout Asia and Europe. By 30,000 years ago, the archaic humans had vanished, and modern humans had taken their place. How did that happen?

From the results of early DNA studies in the late 1980s and early ’90s, scientists argued that anatomically modern humans evolved in Africa, and then expanded into Asia, Oceania, and Europe, beginning about 60,000 years ago. The idea was that modern humans colonized the rest of the world in a succession of small founding groups — each one a tiny sampling of the total modern human gene pool. These small, isolated groups settled new territory and replaced the archaic humans that lived there. As a result, humans in different parts of the world today have their own distinctive DNA signature, consisting of the genetic quirks of their ancestors who first settled the area, as well as the genetic adaptations to the local environment that evolved later.
There are very few isolated branches of the human family tree. People in nearly every part of the world are a product of many different ancient populations, and sometimes surprisingly close relationships span a wide geographical distance.

This view of human history, called the “serial founder effect model,” has big implications for our understanding of how we came to be who we are. Most importantly, under this model, genetic differences between geographically separated human populations reflect deep branchings in the human family tree, branches that go back tens of thousands of years. It also declares that people have evolutionary adaptations that are matched to their geographical area, such as lighter skin in Asians and Europeans or high altitude tolerance among Andeans and Tibetans. With a few exceptions, such as the genetic mixing after Europeans colonized the Americas, our geography reflects our deep ancestry.

Well, it’s time to scrap this picture of human history. [Continue reading...]

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Robert Sapolsky: Are humans just another primate?

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Humans are wired for bad news

Jacob Burak writes: I have good news and bad news. Which would you like first? If it’s bad news, you’re in good company – that’s what most people pick. But why?

Negative events affect us more than positive ones. We remember them more vividly and they play a larger role in shaping our lives. Farewells, accidents, bad parenting, financial losses and even a random snide comment take up most of our psychic space, leaving little room for compliments or pleasant experiences to help us along life’s challenging path. The staggering human ability to adapt ensures that joy over a salary hike will abate within months, leaving only a benchmark for future raises. We feel pain, but not the absence of it.

Hundreds of scientific studies from around the world confirm our negativity bias: while a good day has no lasting effect on the following day, a bad day carries over. We process negative data faster and more thoroughly than positive data, and they affect us longer. Socially, we invest more in avoiding a bad reputation than in building a good one. Emotionally, we go to greater lengths to avoid a bad mood than to experience a good one. Pessimists tend to assess their health more accurately than optimists. In our era of political correctness, negative remarks stand out and seem more authentic. People – even babies as young as six months old – are quick to spot an angry face in a crowd, but slower to pick out a happy one; in fact, no matter how many smiles we see in that crowd, we will always spot the angry face first. [Continue reading...]

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Why do laughter, smiles and tears look so similar?

Michael Graziano writes: About four thousand years ago, somewhere in the Middle East — we don’t know where or when, exactly — a scribe drew a picture of an ox head. The picture was rather simple: just a face with two horns on top. It was used as part of an abjad, a set of characters that represent the consonants in a language. Over thousands of years, that ox-head icon gradually changed as it found its way into many different abjads and alphabets. It became more angular, then rotated to its side. Finally it turned upside down entirely, so that it was resting on its horns. Today it no longer represents an ox head or even a consonant. We know it as the capital letter A.

The moral of this story is that symbols evolve.

Long before written symbols, even before spoken language, our ancestors communicated by gesture. Even now, a lot of what we communicate to each other is non-verbal, partly hidden beneath the surface of awareness. We smile, laugh, cry, cringe, stand tall, shrug. These behaviours are natural, but they are also symbolic. Some of them, indeed, are pretty bizarre when you think about them. Why do we expose our teeth to express friendliness? Why do we leak lubricant from our eyes to communicate a need for help? Why do we laugh?

One of the first scientists to think about these questions was Charles Darwin. In his 1872 book, The Expression of the Emotions in Man and Animals, Darwin observed that all people express their feelings in more or less the same ways. He argued that we probably evolved these gestures from precursor actions in ancestral animals. A modern champion of the same idea is Paul Ekman, the American psychologist. Ekman categorised a basic set of human facial expressions — happy, frightened, disgusted, and so on — and found that they were the same across widely different cultures. People from tribal Papua New Guinea make the same smiles and frowns as people from the industrialised USA.

Our emotional expressions seem to be inborn, in other words: they are part of our evolutionary heritage. And yet their etymology, if I can put it that way, remains a mystery. Can we trace these social signals back to their evolutionary root, to some original behaviour of our ancestors? To explain them fully, we would have to follow the trail back until we left the symbolic realm altogether, until we came face to face with something that had nothing to do with communication. We would have to find the ox head in the letter A.

I think we can do that. [Continue reading...]

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The way we live our lives in stories

Jonathan Gottschall: There’s a big question about what it is that makes people people. What is it that most sets our species apart from every other species? That’s the debate that I’ve been involved in lately.

When we call the species homo sapiens that’s an argument in the debate. It’s an argument that it is our sapience, our wisdom, our intelligence, or our big brains that most sets our species apart. Other scientists, other philosophers have pointed out that, no, a lot of the time we’re really not behaving all that rationally and reasonably. It’s our upright posture that sets us apart, or it’s our opposable thumb that allows us to do this incredible tool use, or it’s our cultural sophistication, or it’s the sophistication of language, and so on and so forth. I’m not arguing against any of those things, I’m just arguing that one thing of equal stature has typically been left off of this list, and that’s the way that people live their lives inside stories.

We live in stories all day long—fiction stories, novels, TV shows, films, interactive video games. We daydream in stories all day long. Estimates suggest we just do this for hours and hours per day — making up these little fantasies in our heads, these little fictions in our heads. We go to sleep at night to rest; the body rests, but not the brain. The brain stays up at night. What is it doing? It’s telling itself stories for about two hours per night. It’s eight or ten years out of our lifetime composing these little vivid stories in the theaters of our minds.

I’m not here to downplay any of those other entries into the “what makes us special” sweepstakes. I’m just here to say that one thing that has been left off the list is storytelling. We live our lives in stories, and it’s sort of mysterious that we do this. We’re not really sure why we do this. It’s one of these questions — storytelling — that falls in the gap between the sciences and the humanities. If you have this division into two cultures: you have the science people over here in their buildings, and the humanities people over here in their buildings. They’re writing in their own journals, and publishing their own book series, and the scientists are doing the same thing.

You have this division, and you have all this area in between the sciences and the humanities that no one is colonizing. There are all these questions in the borderlands between these disciplines that are rich and relatively unexplored. One of them is storytelling and it’s one of these questions that humanities people aren’t going to be able to figure out on their own because they don’t have a scientific toolkit that will help them gradually, painstakingly narrow down the field of competing ideas. The science people don’t really see these questions about storytelling as in their jurisdiction: “This belongs to someone else, this is the humanities’ territory, we don’t know anything about it.”

What is needed is fusion — people bringing together methods, ideas, approaches from scholarship and from the sciences to try to answer some of these questions about storytelling. Humans are addicted to stories, and they play an enormous role in human life and yet we know very, very little about this subject. [Continue reading... or watch a video of Gottschall's talk.]

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Humanity at the crossroads: Sheldon Solomon on the work of Ernest Becker

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When chance surpasses reason

Michael Schulson writes: In the 1970s, a young American anthropologist named Michael Dove set out for Indonesia, intending to solve an ethnographic mystery. Then a graduate student at Stanford, Dove had been reading about the Kantu’, a group of subsistence farmers who live in the tropical forests of Borneo. The Kantu’ practise the kind of shifting agriculture known to anthropologists as swidden farming, and to everyone else as slash-and-burn. Swidden farmers usually grow crops in nutrient-poor soil. They use fire to clear their fields, which they abandon at the end of each growing season.

Like other swidden farmers, the Kantu’ would establish new farming sites ever year in which to grow rice and other crops. Unlike most other swidden farmers, the Kantu’ choose where to place these fields through a ritualised form of birdwatching. They believe that certain species of bird – the Scarlet-rumped Trogon, the Rufous Piculet, and five others – are the sons-in-law of God. The appearances of these birds guide the affairs of human beings. So, in order to select a site for cultivation, a Kantu’ farmer would walk through the forest until he spotted the right combination of omen birds. And there he would clear a field and plant his crops.

Dove figured that the birds must be serving as some kind of ecological indicator. Perhaps they gravitated toward good soil, or smaller trees, or some other useful characteristic of a swidden site. After all, the Kantu’ had been using bird augury for generations, and they hadn’t starved yet. The birds, Dove assumed, had to be telling the Kantu’ something about the land. But neither he, nor any other anthropologist, had any notion of what that something was.

He followed Kantu’ augurers. He watched omen birds. He measured the size of each household’s harvest. And he became more and more confused. Kantu’ augury is so intricate, so dependent on slight alterations and is-the-bird-to-my-left-or-my-right contingencies that Dove soon found there was no discernible correlation at all between Piculets and Trogons and the success of a Kantu’ crop. The augurers he was shadowing, Dove told me, ‘looked more and more like people who were rolling dice’. [Continue reading...]

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When we were fish

Nautilus: Neil Shubin has been going backward his whole life. “I teach anatomy but I want to understand why things look the way they do,” says the paleontologist and professor of organismal biology and anatomy at the University of Chicago. “And to understand the fundamental questions you have to go ever deeper into history. So I have gone backward from humans to fish to planets.”

Shubin, 53, is referring to his two books, Your Inner Fish and The Universe Within, which detail the atoms and molecules, genes and cells, sculpted by evolution into the common bonds of life. In 2004, on Ellesmere Island in the Arctic, Shubin discovered one of the key links in animal evolution, the fish known as Tiktaalik, that, he writes, “was specialized for a rather extraordinary function: it was capable of doing push-ups.”

Shubin and his team learned from Tiktaalik fossils that the big fish with the flat head had a shoulder, elbow, and wrist composed of the same bones in a human’s upper arm, forearm, and wrist. Tiktaalik used those bones to navigate shallow streams and ponds “and even to flop around on the mudflats along the banks.” Here was the creature from the lagoon that revealed how animals evolved from fish to us. [Continue reading...]

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Prehistoric skeleton in Mexico links modern Native Americans to Siberians

The New York Times reports: Most geneticists agree that Native Americans are descended from Siberians who crossed into America 26,000 to 18,000 years ago via a land bridge over the Bering Strait. But while genetic analysis of modern Native Americans lends support to this idea, strong fossil evidence has been lacking.

Now a nearly complete skeleton of a prehistoric teenage girl, newly discovered in an underwater cave in the Yucatán Peninsula, establishes a clear link between the ancient and modern peoples, scientists say.

Writing in the journal Science, the researchers report that they analyzed mitochondrial DNA — genetic material passed down through the mother — that was extracted from the skeleton’s wisdom tooth by divers. The analysis reveals that the girl, who lived at least 12,000 years ago, belonged to an Asian-derived genetic lineage seen only in Native Americans. [Continue reading...]

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Neanderthals were not less intelligent than modern humans, scientists find

The Guardian reports: Scientists have concluded that Neanderthals were not the primitive dimwits they are commonly portrayed to have been.

The view of Neanderthals as club-wielding brutes is one of the most enduring stereotypes in science, but researchers who trawled the archaeological evidence say the image has no basis whatsoever.

They said scientists had fuelled the impression of Neanderthals being less than gifted in scores of theories that purport to explain why they died out while supposedly superior modern humans survived.

Wil Roebroeks at Leiden University in the Netherlands said: “The connotation is generally negative. For instance, after incidents with the Dutch Ajax football hooligans about a week ago, one Dutch newspaper piece pleaded to make football stadiums off-limits for such ‘Neanderthals’.”

The Neanderthals are believed to have lived between roughly 350,000 and 40,000 years ago, their populations spreading from Portugal in the west to the Altai mountains in central Asia in the east. They vanished from the fossil record when modern humans arrived in Europe.

The reasons for the demise of the Neanderthals have long been debated in the scientific community, but many explanations assume that modern humans had a cognitive edge that manifested itself in more cooperative hunting, better weaponry and innovation, a broader diet, or other major advantages.

Roebroeks and his colleague, Dr Paola Villa at the University of Colorado Museum in Boulder, trawled through the archaeological records to look for evidence of modern human superiority that underpinned nearly a dozen theories about the Neanderthals’ demise and found that none of them stood up.

“The explanations make good stories, but the only problem is that there is no archaeology to back them up,” said Roebroeks.

Villa said part of the misunderstanding had arisen because researchers compared Neanderthals with their successors, the modern humans who lived in the Upper Palaeolithic, rather than the humans who lived at the same time. That is like saying people in the 19th century were less intelligent than those in the 21st because they didn’t have laptops and space travel.

“The evidence for cognitive inferiority is simply not there,” said Villa. “What we are saying is that the conventional view of Neanderthals is not true.” The study is published in the journal Plos One. [Continue reading...]

It’s always worth remembering that modernity as it is lived (rather than as it is written about) is nothing more than a name for the present — that point which stands right on the edge of an unknown future. In this sense all humans and other hominids have lived in a modern condition and their innovations have been defined by what was contemporary.

If comparisons can usefully be made between humans and their closest kin at different points in history, rather than judge them on the basis of the artifacts they have created, a more interesting question is how well each has been attuned to the environment that supports them.

That attunement probably cannot be scientifically quantified since in part it would have to be measured through attributes that might leave no physical traces — such as knowledge about the medicinal properties of plants.

Since the arc of human progress has largely been defined by our increasing ability to cut ourselves off from the world in which we live, in terms of environmental attunement, the human of today is less advanced than a Neanderthal.

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Paleoanthropologists use models to show humans may have left Africa earlier than thought

Phys.org reports: A team of European researchers is suggesting that humans dispersed out of Africa in multiple waves, rather than in just one, and that it occurred much earlier than has been previously thought. In their paper published in Proceedings of the National Academy of Sciences, the group describes how they built migration models based on gene flow and skull characteristics to predict human migration out of Africa.

Scientists have generally agreed that humans first migrated out of Africa 40,000 to 70,000 years ago, culminating in settlements that span the globe. That estimate has been rocked in recent years however, by discoveries of stone artifacts in the Arabian Desert that date back at least 100,000 years (close to the time that modern humans were thought to have arisen). In this new effort, the researchers have expanded on the idea that humans may have left Africa sooner than most had thought, and that it likely happened via multiple routes, rather than just one.

The models the team built took into account genetic dispersal and human skull shape—they created four possible model scenarios of migration—two that showed a single path out of Africa and two that showed multiple paths. The first of the single migration paths involved people traveling north along the Nile valley then turning right when they hit the Mediterranean Sea. The second involved people meandering along the Arabian Peninsula until making their way to Asia. The multi-path migration models involved people marching out of Africa along several paths, both north and south of the Arabian Peninsula. [Continue reading...]

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Hunter-gatherers have healthier guts than urban dwellers

Nature Communications reports: The gut microbiota is responsible for many aspects of human health and nutrition, but most studies have focused on “western” populations. An international collaboration of researchers, including researchers of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has for the first time analysed the gut microbiota of a modern hunter-gatherer community, the Hadza of Tanzania. The results of this work show that Hadza harbour a unique microbial profile with features yet unseen in any other human group, supporting the notion that Hadza gut bacteria play an essential role in adaptation to a foraging subsistence pattern. The study further shows how the intestinal flora may have helped our ancestors adapt and survive during the Paleolithic.

Bacterial populations have co-evolved with humans over millions of years, and have the potential to help us adapt to new environments and foods. Studies of the Hadza offer an especially rare opportunity for scientists to learn how humans survive by hunting and gathering, in the same environment and using similar foods as our ancestors did.

The research team, composed of anthropologists, microbial ecologists, molecular biologists, and analytical chemists, and led in part by Stephanie Schnorr and Amanda Henry of the Max Planck Institute for Evolutionary Anthropology, compared the Hadza gut microbiota to that of urban living Italians, representative of a “westernized” population. Their results, published recently in Nature Communications, show that the Hadza have a more diverse gut microbe ecosystem, i.e. more bacterial species compared to the Italians. “This is extremely relevant for human health”, says Stephanie Schnorr. “Several diseases emerging in industrialized countries, like IBS, colorectal cancer, obesity, type II diabetes, Crohn’s disease and others, are significantly associated with a reduction in gut microbial diversity.” [Continue reading...]

Jeff Leach recently accompanied some Hadza hunters and observed the way they handled a recently killed adult Impala: Before the two Hadza men I was with jumped in to help skin and gut the Impala, I quickly took swabs of each of their hands (and 1 hour after, 3 hours after, and so on) to assess how the skin (palm) microbiota change throughout the day/week of a typical Hadza (We’ve sampled the hands [and stools] of 150+ Hadza men, women, and children so far). As they slowly and methodically dismembered the animal, they carefully placed the stomach and its still steaming contents on the fleshy side of the recently removed hide. In a separate area, they piled the fatty internal organs (which men are only allowed to eat by the way). Once the animal had been processed more or less, I was amazed to see all three men take a handful of the partially digested plant material from the recently removed stomach to scrub off the copious amounts of blood that now covered their hands and foreman’s. This was followed by a final “cleaning” with dry grass for good measure.

While I was fascinated by the microbe-laden stomach contents being used as hand scrubber – presumably transferring an extraordinary diversity of microbes from the Impala gut to the hands of the Hadza – I was not prepared for what they did next. Once they had cleaned out – by hand – the contents of the stomach (“cleaned” is a generous word), they carved pieces of the stomach into bite-sized chunks and consumed it sushi-style. By which I mean they didn’t cook it or attempt to kill or eliminate the microbes from the gut of the Impala in anyway. And if this unprecedented transfer of microbes from the skin, blood, and stomach of another mammal wasn’t enough, they then turned their attention to the colon of the Impala.

After removing the poo pellets (which we collect samples of as well), they tossed the tubular colon onto a hastily built fire. However, it only sat on the fire for a minute at best and clearly not long enough to terminate the menagerie of invisible microbes clinging to the inside wall of the colon. They proceeded to cut the colon into chunks and to eat more or less raw. For myself, I kindly turned down offers to taste either the raw stomach or the partially cooked colon – but did eat some tasty Impala ribs I thoroughly turned on a stick over the fire to a microbial-free state of well done.

The Hadza explained that this is what they always do, and have always done (though I suspect sushi-style eating of innards is not an every-kill ritual. But….). Whether it’s an Impala, Dik Dik, Zebra, bush pig, Kudu or any other of the myriad of mammals they hunt and eat, becoming one with the deceased’s microbes in any number of ways is common place – same goes for 700 plus species of birds they hunt (minus abundant amounts of stomach contents for hand sanitizer!). While less obvious than at the “kill site,” the transfer of microbes continued back in camp when women, children and other men handled the newly arrived raw meat, internal organs, and skin. The transfer continued as the hunters engaged (touching) other members of the camp.

The breathtaking exchange (horizontal transfer) of microbes between the Hadza and their environment is more or less how it’s been for eons until humans started walling ourselves off from the microbial world through the many facets of globalization. Rather than think of ourselves as isolated islands of microbes, the Hadza teach us that we are better thought of as an archipelago of islands, once seamlessly connected to one another and to a larger metacommunity of microbes via a microbial super highway that runs through the gut and skin/feathers of every animal and water source on the landscape (for those of you keeping up with your homework, this is Macroecology 101). The same can be said for plants and their extraordinary diversity of microbes above (phyllosphere) and below ground (rhizosphere) that the Hadza, and once all humans, interacted with on a nearly continuous basis.

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Cahokia: North America’s first melting pot?

Christian Science Monitor: The first experiment in “melting pot” politics in North America appears to have emerged nearly 1,000 years ago in the bottom lands of the Mississippi River near today’s St. Louis, according to archaeologists piecing together the story of the rise and fall of the native American urban complex known as Cahokia.

During its heyday, Cahokia’s population reached an estimated 20,000 people – a level the continent north of the Rio Grande wouldn’t see again until the eve of the American Revolution and the growth of New York and Philadelphia.

Cahokia’s ceremonial center, seven miles northeast of St. Louis’s Gateway Arch, boasted 120 earthen mounds, including a broad, tiered mound some 10 stories high. In East St. Louis, one of two major satellites hosts another 50 earthen mounds, as well as residences. St. Louis hosted another 26 mounds and associated dwellings.

These are three of the four largest native-American mound centers known, “all within spitting distance of one another,” says Thomas Emerson, Illinois State Archaeologist and a member of a team testing the melting-pot idea. “That’s some kind of large, integrated complex to some degree.”

Where did all those people come from? Archaeologists have been debating that question for years, Dr. Emerson says. Unfortunately, the locals left no written record of the complex’s history. Artifacts such as pottery, tools, or body ornaments give an ambiguous answer.

Artifacts from Cahokia have been found in other native-American centers from Arkansas and northern Louisiana to Oklahoma, Iowa, and Wisconsin, just as artifacts from these areas appear in digs at Cahokia.

“Archaeologists are always struggling with this: Are artifacts moving, or are people moving?” Emerson says.

Emerson and two colleagues at the University of Illinois at Urbana-Champaign tried to tackle the question using two radioactive forms of the element strontium found in human teeth. They discovered that throughout the 300 years that native Americans occupied Cahokia, the complex appeared to receive a steady stream of immigrants who stayed. [Continue reading...]

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Throughout our existence humans have always been the most destructive creatures to roam this planet

woolly-mammoth

For those of us who see industrial civilization as the guarantor of humanity’s destruction, it’s easy to picture an idyllic era earlier in our evolution, located perhaps during the cultural flowering of the Great Leap Forward.

Communities then remained relatively egalitarian without workers enslaved in back-breaking labor, while subsistence on few material resources meant that time was neither controlled by the dictates of a stratified social hierarchy nor by the demands of survival.

When people could accord as much value to storytelling, ritual, and music-making, as they did to hunting and gathering food, we might like to think that human beings were living in balance with nature.

As George Monbiot reveals, the emerging evidence about of our early ancestors paints a much grimmer picture — one in which human nature appears to have always been profoundly destructive.

You want to know who we are? Really? You think you do, but you will regret it. This article, if you have any love for the world, will inject you with a venom – a soul-scraping sadness – without an obvious antidote.

The Anthropocene, now a popular term among scientists, is the epoch in which we live: one dominated by human impacts on the living world. Most date it from the beginning of the industrial revolution. But it might have begun much earlier, with a killing spree that commenced two million years ago. What rose onto its hind legs on the African savannahs was, from the outset, death: the destroyer of worlds.

Before Homo erectus, perhaps our first recognisably human ancestor, emerged in Africa, the continent abounded with monsters. There were several species of elephants. There were sabretooths and false sabretooths, giant hyenas and creatures like those released in The Hunger Games: amphicyonids, or bear dogs, vast predators with an enormous bite.

Prof Blaire van Valkenburgh has developed a means by which we could roughly determine how many of these animals there were. When there are few predators and plenty of prey, the predators eat only the best parts of the carcass. When competition is intense, they eat everything, including the bones. The more bones a carnivore eats, the more likely its teeth are to be worn or broken. The breakages in carnivores’ teeth were massively greater in the pre-human era.

Not only were there more species of predators, including species much larger than any found on Earth today, but they appear to have been much more abundant – and desperate. We evolved in a terrible, wonderful world – that was no match for us. [Continue reading...]

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Talking Neanderthals challenge assumptions about the origins of speech

University of New England, Australia: We humans like to think of ourselves as unique for many reasons, not least of which being our ability to communicate with words. But ground-breaking research by an expert from the University of New England shows that our ‘misunderstood cousins,’ the Neanderthals, may well have spoken in languages not dissimilar to the ones we use today.

Pinpointing the origin and evolution of speech and human language is one of the longest running and most hotly debated topics in the scientific world. It has long been believed that other beings, including the Neanderthals with whom our ancestors shared the Earth for thousands of years, simply lacked the necessary cognitive capacity and vocal hardware for speech.

Associate Professor Stephen Wroe, a zoologist and palaeontologist from UNE, along with an international team of scientists and the use of 3D x-ray imaging technology, made the revolutionary discovery challenging this notion based on a 60,000 year-old Neanderthal hyoid bone discovered in Israel in 1989.

“To many, the Neanderthal hyoid discovered was surprising because its shape was very different to that of our closest living relatives, the chimpanzee and the bonobo. However, it was virtually indistinguishable from that of our own species. This led to some people arguing that this Neanderthal could speak,” A/Professor Wroe said.

“The obvious counterargument to this assertion was that the fact that hyoids of Neanderthals were the same shape as modern humans doesn’t necessarily mean that they were used in the same way. With the technology of the time, it was hard to verify the argument one way or the other.”

However advances in 3D imaging and computer modelling allowed A/Professor Wroe’s team to revisit the question.

“By analysing the mechanical behaviour of the fossilised bone with micro x-ray imaging, we were able to build models of the hyoid that included the intricate internal structure of the bone. We then compared them to models of modern humans. Our comparisons showed that in terms of mechanical behaviour, the Neanderthal hyoid was basically indistinguishable from our own, strongly suggesting that this key part of the vocal tract was used in the same way.

“From this research, we can conclude that it’s likely that the origins of speech and language are far, far older than once thought.”

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The emotional intelligence of dogs

f13-iconThe ability to discern the emotions of others provides the foundation for emotional intelligence. How well-developed this faculty is seems to have little to do with the strength of other markers of intelligence, indeed, as a new study seems to imply, there may be little reason to see in emotional intelligence much that is uniquely human.

Scientific American: [A]lthough dogs have the capacity to understand more than 100 words, studies have demonstrated Fido can’t really speak human languages or comprehend them with the same complexity that we do. Yet researchers have now discovered that dog and human brains process the vocalizations and emotions of others more similarly than previously thought. The findings suggest that although dogs cannot discuss relativity theory with us, they do seem to be wired in a way that helps them to grasp what we feel by attending to the sounds we make.

To compare active human and dog brains, postdoctoral researcher Attila Andics and his team from MTA-ELTE Comparative Ethology Research Group in Hungary trained 11 dogs to lie still in an fMRI brain scanner for several six minute intervals so that the researchers could perform the same experiment on both human and canine participants. Both groups listened to almost two hundred dog and human sounds — from whining and crying to laughter and playful barking — while the team scanned their brain activity.

The resulting study, published in Current Biology today, reveals both that dog brains have voice-sensitive regions and that these neurological areas resemble those of humans. Sharing similar locations in both species, they process voices and emotions of other individuals similarly. Both groups respond with greater neural activity when they listen to voices reflecting positive emotions such as laughing than to negative sounds that include crying or whining. Dogs and people, however, respond more strongly to the sounds made by their own species. “Dogs and humans meet in a very similar social environment but we didn’t know before just how similar the brain mechanisms are to process this social information,” Andics says. [Continue reading...]

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900,000 year old footprints of earliest northern Europeans discovered

f13-iconThe Telegraph reports: Footprints left behind by what may be one our first human ancestors to arrive in Britain have been discovered on a beach in Norfolk.

The preserved tracks, which consisted of 49 imprints in a soft sedimentary rock, are believed to be around 900,000 years old and could transform scientists understanding of how early humans moved around the world.

The footprints were found in what scientists have described as a “million to one” discovery last summer when heavy seas washed sand off the foreshore in Happisburgh, Norfolk.

The find has only now been made public and are thought to be the oldest evidence of early humans in northern Europe yet to be discovered. [Continue reading...]

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