The stunning underwater picture this photographer wishes ‘didn’t exist’

Lindsey Bever writes: The powerful and poignant image shows a tiny sea horse holding tightly onto a pink, plastic cotton swab in blue-green waters around Indonesia.

California nature photographer Justin Hofman snapped the picture late last year off the coast of Sumbawa, an Indonesian island in the Lesser Sunda Islands chain. The 33-year-old, from Monterey, Calif., said a colleague pointed out the pocket-size sea creature, which he estimated to be about 1.5 inches tall — so small, in fact, that Hofman said he almost didn’t reach for his camera.

“The wind started to pick up and the sea horse started to drift. It first grabbed onto a piece of sea grass,” Hofman said Thursday in a phone interview.

Hofman started shooting.

“Eventually more and more trash and debris started to move through,” he said, adding that the critter lost its grip, then latched onto a white, wispy piece of a plastic bag. “The next thing it grabbed was a Q-Tip.”

Hofman said he wishes the picture “didn’t exist” — but it does; and now, he said, he feels responsible “to make sure it gets to as many eyes as possible.” [Continue reading…]

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Our imaginative life today has access to the pre-linguistic, ancestral mind

Stephen T Asma writes: Richard Klein, Maurice Bloch and other prominent paleoanthropologists place the imagination quite late in the history of our species, thousands of years after the emergence of anatomically modern humans. In part, this theory reflects a bias that artistic faculties are a kind of evolutionary cheesecake – sweet desserts that emerge as byproducts of more serious cognitive adaptations such as language and logic. More importantly, it is premised on the relatively late appearance of cave art in the Upper Paleolithic period (c38,000 years ago). It is common for archaeologists to assume that imagination evolves late, after language, and the cave paintings are a sign of modern minds at work, thinking and creating just as we do today.

Contrary to this interpretation, I want to suggest that imagination, properly understood, is one of the earliest human abilities, not a recent arrival. Thinking and communicating are vastly improved by language, it is true. But ‘thinking with imagery’ and even ‘thinking with the body’ must have preceded language by hundreds of thousands of years. It is part of our mammalian inheritance to read, store and retrieve emotionally coded representations of the world, and we do this via conditioned associations, not propositional coding.

Lions on the savanna, for example, learn and make predictions because experience forges strong associations between perception and feeling. Animals appear to use images (visual, auditory, olfactory memories) to navigate novel territories and problems. For early humans, a kind of cognitive gap opened up between stimulus and response – a gap that created the possibility of having multiple responses to a perception, rather than one immediate response. This gap was crucial for the imagination: it created an inner space in our minds. The next step was that early human brains began to generate information, rather than merely record and process it – we began to create representations of things that never were but might be. On this view, imagination extends back into the Pleistocene, at least, and likely emerged slowly in our Homo erectus cousins. [Continue reading…]

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‘Uncontacted’ Amazon tribe members are reported killed in Brazil

The New York Times reports: They were members of an uncontacted tribe gathering eggs along the river in a remote part of the Amazon. Then, it appears, they had the bad luck of running into gold miners.

Now, federal prosecutors in Brazil have opened an investigation into the reported massacre of about 10 members of the tribe, the latest evidence that threats to endangered indigenous groups are on the rise in the country.

The Brazilian agency on indigenous affairs, Funai, said it had lodged a complaint with the prosecutor’s office in the state of Amazonas after the gold miners went to a bar in a near the border with Colombia, and bragged about the killings. They brandished a hand-carved paddle that they said had come from the tribe, the agency said.

“It was crude bar talk,” said Leila Silvia Burger Sotto-Maior, Funai’s coordinator for uncontacted and recently contacted tribes. “They even bragged about cutting up the bodies and throwing them in the river.”

The miners, she said, claimed that “they had to kill them or be killed.”

Ms. Sotto-Maior said the killings were reported to have taken place last month. The indigenous affairs bureau conducted some initial interviews in the town and then took the case to the police.

“There is a lot of evidence, but it needs to be proven,” she said.

The prosecutor in charge of the case, Pablo Luz de Beltrand, confirmed that an investigation had begun, but said he could not discuss the details of the case while it was underway. He said the episode was alleged to have occurred in the Javari Valley — the second-largest indigenous reserve in Brazil — in the remote west.

“We are following up, but the territories are big and access is limited,” Mr. Beltrand said. “These tribes are uncontacted — even Funai has only sporadic information about them. So it’s difficult work that requires all government departments working together.”

Mr. Beltrand said it was the second such episode that he was investigating this year. The first reported killing of uncontacted Indians in the region occurred in February, and that case is still open. “It was the first time that we’d had this kind of case in this region,” he said in a telephone interview. “It’s not something that was happening before.”

Survival International, a global indigenous rights group, warned that given the small sizes of the uncontacted Amazon tribes, this latest episode could mean that a significant percentage of a remote ethnic group was wiped out.

“If the investigation confirms the reports, it will be yet another genocidal massacre resulting directly from the Brazilian government’s failure to protect isolated tribes — something that is guaranteed in the Constitution,” said Sarah Shenker, a senior campaigner with the rights group.

Under Brazil’s president, Michel Temer, funding for indigenous affairs has been slashed. In April, Funai closed five of the 19 bases that it uses to monitor and protect isolated tribes, and reduced staffing at others. The bases are used to prevent invasions by loggers and miners and to communicate with recently contacted tribes. [Continue reading…]

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Why do people die fighting for a cause?

Science reports: To beat your enemies, you must understand them intimately. And so anthropologist Scott Atran and his colleagues have spent the last 2 years interviewing Islamic State group fighters and their opponents on the front lines. For a study published yesterday in Nature Human Behavior, Atran, director of research at Artis International, a research institute based in Scottsdale, Arizona, and his research team personally talked with extremists in the field, whom they’d reached through local leaders. They also conducted online surveys with thousands of Spanish citizens in order to include a more pacific population. Science spoke with Atran, who also holds positions at the University of Michigan in Ann Arbor, the University of Oxford in the United Kingdom, and France’s CNRS in Paris, about his work. This interview has been edited for brevity and clarity.

Q: What makes someone willing to die fighting for a cause?

A: Well, lots of things, but what best predicted willingness to die on the battlefront was both devotion to a tight-knit group of comrades—fusion with them—and commitment to sacred values. But the values actually trumped the group, which may be the first time that was shown. Because most of the military sociology and psychology, at least since World War II, has said that will to fight is based on camaraderie and fighting for your buddies.

In September 2014, [then-President Barack] Obama’s national security director said the greatest mistake the U.S. made in Iraq was underestimating ISIS’s will to fight, and he said it was similar in Vietnam. And then he said will to fight is an imponderable, which is why we undertook this study.

Q: What are sacred values?

A: They are moral values. We’ve shown in lots of different contexts that sacred values are immune or resistant to material trade-offs. You wouldn’t sell your children or sell out your country or your religion for all the money in China. Another aspect is that they generate actions because they’re the right thing to do, so you’re not really worried about risks or rewards or cost or consequences. [Continue reading…]

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How the Folsom point became an archaeological icon

Stephen E. Nash writes: The Folsom spear point, which was excavated in 1927 near the small town of Folsom, New Mexico, is one of the most famous artifacts in North American archaeology, and for good reason: It was found in direct association with the bones of an extinct form of Ice Age bison. The Folsom point therefore demonstrated conclusively, and for the first time, that human beings were in North America during the last Ice Age—thousands of years earlier than previously thought.

The Folsom discovery marked the end of a long series of sometimes serendipitous, sometimes deliberate actions by an intriguing cast of characters. As such, it helps us understand that archaeology—like most fields of study—has very few “Eureka!” moments in which a brilliant sage comes upon an insight that suddenly changes the world. Instead, archaeology is cumulative, often slow, and painstaking. And while an individual artifact can indeed be important, it’s context (where it was found) and association (what it was found with) are often more important than the object itself.

The story begins in 1908. In the late afternoon heat of August 27, an unusually strong summer thunderstorm dropped 13 inches of rain—75 percent of the yearly average—on Johnson Mesa, northwest of Folsom. The resulting flash flood swept through the town and the usually dry drainages in the vicinity. In so doing, it exposed buried features and artifacts that hadn’t seen the light of day in thousands of years. [Continue reading…]

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Here’s what the last common ancestor of apes and humans looked like

Charles Q. Choi writes: The most complete extinct-ape skull ever found reveals what the last common ancestor of all living apes and humans might have looked like, according to a new study.

The 13-million-year-old infant skull, which its discoverers nicknamed “Alesi,” was unearthed in Kenya in 2014. It likely belonged to a fruit-eating, slow-climbing primate that resembled a baby gibbon, the researchers said.

Among the living primates, humans are most closely related to the apes, which include the lesser apes (gibbons) and the great apes (chimpanzees, gorillas and orangutans). These so-called hominoids — that is, the gibbons, great apes and humans — emerged and diversified during the Miocene epoch, approximately 23 million to 5 million years ago. (The last common ancestor that humans had with chimpanzees lived about 6 million to 7 million years ago.)

Much remains unknown about the common ancestors of living apes and humans from the critical time when these branches diverged. Fossil evidence from this part of the primate family tree is scarce, and consists mostly of isolated teeth and broken jaw fragments. As such, researchers were not sure what the last common ancestors of living apes and humans might have looked like, and even whether they originated in Africa or Eurasia. [Continue reading…]

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Democracy as contained conflict

Saul Frampton writes: The fall of Mycenaean power, the intervening Dark Ages, and the dawn of a new civilisation during the ‘Greek miracle’ of the Archaic period is one of the most fascinating stories in ancient history. After the collapse of the Mycenaean palace system around 1100 BCE, Greece experienced centuries of social and economic devastation. Pylos, Mycenae and Thebes were abandoned and burned to the ground. A dwindling population was attacked by invaders from the north and from the sea. What remained of Bronze Age culture was according to one historian ‘very little’, and ‘that little then dwindled away to almost nothing’. Writing at the end of the period, the 8th-century poet Hesiod described the degeneration of the human race, from glittering Bronze Age heroes, down to his own violent ‘Age of Iron’. He looked into the near future and saw children born grey, families at war with themselves, and society self-destructing. He concluded miserably: ‘I wish that I … had either died sooner or been born later.’

But it was at this moment that a new vision of society began to emerge. As the classical scholar Gilbert Murray put it in 1907 : ‘There is a far-off island of knowledge, or apparent knowledge; then darkness; then the beginnings of continuous history.’ The archaic period (800-480 BCE) represents the start of this history, when ‘darkness gives way to dawn’, according to the archaeologist J N Coldstream. And at its heart is the birthplace of the Western intellectual and political tradition: the polis or Greek city-state.

A polis was a self-governing city or town and its surrounding territory. In terms of size, it wasn’t necessarily big: Aristotle said that all the citizens of a polis (i.e, men) should be able to be assembled by the voice of a single herald. Plato gave an ideal citizenry of 5,040. Some poleis were smaller, but few were much larger. A typical city-state such as Plataea in Boeotia had a total population of fewer than 10,000. But from its modest beginnings, the idea of the polis soon spread. At the highpoint of Greek civilisation (c400 BCE), around 1,000 had migrated across the shores of the Mediterranean – as Plato put it: ‘like frogs around a pond’.

Given these geographic variations, many chose to define the polis anthropologically. ‘Not well-built walls, nor canals and dockyards make the polis: but men do,’ said Alcaeus of Lesbos. In Thucydides, the Athenian general Nikias states that: ‘It is men that make the polis, not walls or ships.’ Aristotle defined man as politikon zoon, a political animal: he ‘whose nature is to live in a polis’. At its heart was a conception of government for the people, by the people: of normative rules and collective decision-making. For the writers and philosophers of 5th-century Athens, this culminated in an ability to step back, not only from politics but from life itself, and subject it to something like objective scrutiny.

But the reasons for the success of the Greek city-state still remain unclear. Did it result from an expanding population or the group-think of the armoured hoplite phalanx? Were improvements in trade crucial, or was it the rise of sophisticated urban elites? Was it maintained by abstract ideals of democracy (demokratia), freedom (eleutheria) and free speech (parrhesia)? Or was the rise of the polis somehow the astonishing aftereffect of the simple act of drawing a line? [Continue reading…]

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Humans first settled in Australia as early as 65,000 years ago

Science News reports: Tools, paints and other artifacts excavated from an ancient rock-shelter in northern Australia are giving new glimpses into early life Down Under. The first humans may have arrived on the continent 65,000 years ago — 5,000 years earlier than previously thought — and they were sophisticated craftspeople, researchers report July 19 in Nature.

Archaeologists unearthed three distinct layers of artifacts at Madjedbebe, Australia’s oldest known site of human habitation, during digs in 2012 and 2015. The oldest, deepest layer contained more than 10,000 relics of human handiwork. This cache included the world’s oldest polished ax heads, Australia’s oldest seed-grinding and pigment-processing tools, stone points that may have been spearheads, as well as hearths and other remnants of human activity.

“When people think about our ancient ancestors, they either tend to have a view that our ancestors must have been primitive, less culturally diverse, or they take the view that our ancestors were probably extraordinarily culturally impressive,” says Peter Hiscock, an archaeologist at the University of Sydney who was not involved in the study. “This indicates the latter view. The moment people get to Australia, they’re doing all this really smart stuff.” They were probably building fires to light nighttime activities, grinding seeds for food and using ochre paints to decorate cave walls or their own bodies, Hiscock says. [Continue reading…]

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In Neanderthal DNA, signs of a mysterious human migration

Carl Zimmer writes: With fossils and DNA, scientists are piecing together a picture of humanity’s beginnings, an origin story with more twists than anything you would find at the movie theater.

The expert consensus now is that Homo sapiens evolved at least 300,000 years ago in Africa. Only much later — roughly 70,000 years ago — did a small group of Africans establish themselves on other continents, giving rise to other populations of people today.

To Johannes Krause, the director of the Max Planck Institute for Human History in Germany, that gap seems peculiar. “Why did people not leave Africa before?” he asked in an interview. After all, he observed, the continent is physically linked to the Near East. “You could have just walked out.”

In a study published Tuesday in Nature Communications, Dr. Krause and his colleagues report that Africans did indeed walk out — over 270,000 years ago.

Based on newly discovered DNA in fossils, the researchers conclude that a wave of early Homo sapiens, or close relatives of our species, made their way from Africa to Europe. There, they interbred with Neanderthals.

Then the ancient African migrants disappeared. But some of their DNA endured in later generations of Neanderthals.

“This is now a comprehensive picture,” Dr. Krause said. “It brings everything together.” [Continue reading…]

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Why your brain hates other people — and how to make it think differently

Robert Sapolsky writes: As a kid, I saw the 1968 version of Planet of the Apes. As a future primatologist, I was mesmerized. Years later I discovered an anecdote about its filming: At lunchtime, the people playing chimps and those playing gorillas ate in separate groups.

It’s been said, “There are two kinds of people in the world: those who divide the world into two kinds of people and those who don’t.” In reality, there’s lots more of the former. And it can be vastly consequential when people are divided into Us and Them, ingroup and outgroup, “the people” (i.e., our kind) and the Others.

Humans universally make Us/Them dichotomies along lines of race, ethnicity, gender, language group, religion, age, socioeconomic status, and so on. And it’s not a pretty picture. We do so with remarkable speed and neurobiological efficiency; have complex taxonomies and classifications of ways in which we denigrate Thems; do so with a versatility that ranges from the minutest of microaggression to bloodbaths of savagery; and regularly decide what is inferior about Them based on pure emotion, followed by primitive rationalizations that we mistake for rationality. Pretty depressing.

But crucially, there is room for optimism. Much of that is grounded in something definedly human, which is that we all carry multiple Us/Them divisions in our heads. A Them in one case can be an Us in another, and it can only take an instant for that identity to flip. Thus, there is hope that, with science’s help, clannishness and xenophobia can lessen, perhaps even so much so that Hollywood-extra chimps and gorillas can break bread together. [Continue reading…]

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Daniel Everett: Becoming human without words for colors, numbers, or time

 

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Oldest Homo sapiens bones ever found shake foundations of the human story

The Guardian reports: Fossils recovered from an old mine on a desolate mountain in Morocco have rocked one of the most enduring foundations of the human story: that Homo sapiens arose in a cradle of humankind in East Africa 200,000 years ago.

Archaeologists unearthed the bones of at least five people at Jebel Irhoud, a former barite mine 100km west of Marrakesh, in excavations that lasted years. They knew the remains were old, but were stunned when dating tests revealed that a tooth and stone tools found with the bones were about 300,000 years old.

“My reaction was a big ‘wow’,” said Jean-Jacques Hublin, a senior scientist on the team at the Max Planck Institute for Evolutionary Anthropology in Leipzig. “I was expecting them to be old, but not that old.”

Hublin said the extreme age of the bones makes them the oldest known specimens of modern humans and poses a major challenge to the idea that the earliest members of our species evolved in a “Garden of Eden” in East Africa one hundred thousand years later.

“This gives us a completely different picture of the evolution of our species. It goes much further back in time, but also the very process of evolution is different to what we thought,” Hublin told the Guardian. “It looks like our species was already present probably all over Africa by 300,000 years ago. If there was a Garden of Eden, it might have been the size of the continent.” [Continue reading…]

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What hyenas can tell us about the origins of intelligence

David Z. Hambrick writes: Physical similarities aside, we share a lot in common with our primate relatives. For example, as Jane Goodall famously documented, chimpanzees form lifelong bonds and show affection in much the same way as humans. Chimps can also solve novel problems, use objects as tools, and may possess “theory of mind”—an understanding that others may have different perspectives than oneself. They can even outperform humans in certain types of cognitive tasks.

These commonalities may not seem all that surprising given what we now know from the field of comparative genomics: We share nearly all of our DNA with chimpanzees and other primates. However, social and cognitive complexity is not unique to our closest evolutionary cousins. In fact, it is abundant in species with which we would seem to have very little in common—like the spotted hyena.

For more than three decades, the Michigan State University zoologist Kay Holekamp has studied the habits of the spotted hyena in Kenya’s Masai Mara National Reserve, once spending five years straight living in a tent among her oft-maligned subjects. One of the world’s longest-running studies of a wild mammal, this landmark project has revealed that spotted hyenas not only have social groups as complex as those of many primates, but are also capable of some of the same types of problem solving.

This research sheds light on one of science’s greatest mysteries—how intelligence has evolved across the animal kingdom. [Continue reading…]

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Jumping genes play a big role in what makes us human

Science News reports: Face-to-face, a human and a chimpanzee are easy to tell apart. The two species share a common primate ancestor, but over millions of years, their characteristics have morphed into easily distinguishable features. Chimps developed prominent brow ridges, flat noses, low-crowned heads and protruding muzzles. Human noses jut from relatively flat faces under high-domed crowns.

Those facial features diverged with the help of genetic parasites, mobile bits of genetic material that insert themselves into their hosts’ DNA. These parasites go by many names, including “jumping genes,” “transposable elements” and “transposons.” Some are relics of former viruses assimilated into a host’s genome, or genetic instruction book. Others are self-perpetuating pieces of genetic material whose origins are shrouded in the mists of time.

“Transposable elements have been with us since the beginning of evolution. Bacteria have transposable elements,” says evolutionary biologist Josefa González. She doesn’t think of transposons as foreign DNA. They are parts of our genomes — like genes.

“You cannot understand the genome without understanding what transposable elements are doing,” says González, of the Institute of Evolutionary Biology in Barcelona. She studies how jumping genes have influenced fruit fly evolution.

Genomes of most organisms are littered with the carcasses of transposons, says Cédric Feschotte, an evolutionary geneticist at the University of Utah in Salt Lake City. Fossils of the DNA parasites build up like the remains of ancient algae that formed the white cliffs of Dover. One strain of maize, the organism in which Nobel laureate Barbara McClintock first discovered transposable elements in the 1940s, is nearly 85 percent transposable elements (SN: 12/19/09, p. 9). Corn is an extreme example, but humans have plenty, too: Transposable elements make up nearly half of the human genome.

Most of the transposons in the genomes of humans and other creatures are now “dead,” meaning they are no longer able to jump. The majority are in bits and pieces scattered throughout the genome like so much confetti. Many researchers used to think these broken transposons were just genetic garbage.

Far from junk, however, jumping gene remnants have been an evolutionary treasure trove. Some of the control switches transposons once used for their own hopping have been recycled over time into useful tools that help species, including Homo sapiens, adapt to their environments or take on new characteristics. [Continue reading…]

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New study claims hominids were in North America 130,000 years ago

Ed Yong writes: In the winter of 1992, a construction crew in San Diego, California started cutting into the rocks that flanked the State 54 Highway, in a bid to widen the road. Those rocks hailed from the Pleistocene period and were rich in Ice Age fossils, so scientists from the San Diego Museum of Natural History accompanied the crew to recover whatever they unearthed. Among bits of horse, camel, dire wolf, and ground sloth, they found the remains of a single mastodon—an extinct mammoth-like animal. “And we noticed there was something different about it,” says Thomas Deméré, who was part of the team.

Based on several lines of evidence—the way the bones are broken, the way they lay, the presence of large stones that show curious patterns of wear and are out-of-place in the surrounding sediment—the team think that early humans used rocks to hammer their way into the mastodon’s bones. That wouldn’t have been contentious in itself, but the team also claims that the bones from the “Cerruti Mastodon” are 130,000 years old. That would push back the earliest archaeological evidence for humans in North America by a whopping 115,000 years.

To put that in perspective, for decades, the first American settlers were thought to be the Clovis people, who arrived 13,000 years ago. But by discovering older sites with strong evidence of human activity, archaeologists confirmed that the continent had a pre-Clovis presence that dates back 14,600 years—or perhaps even further. Genetic studies have also suggested that modern humans entered America from Asia even earlier, around 23,000 years ago. [Continue reading…]

 

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Was the first song a lullaby?

Tom Jacobs writes: Why do humans play, and listen, to music? The question has long baffled evolutionary theorists. Some suggest it had its origins in courtship rituals, while others contend it had (and has) a unique ability to bond people together to work toward a common goal.

Now, a couple of Harvard University researchers have proposed a new concept: They argue that the earliest music  —  and perhaps the prototype for everything from Bach to rap  — may just have been the songs mothers sing to their infants.

Maybe the first musical genre wasn’t the love song, but rather the lullaby.

“The evolution of music must be a complex, multi-step process, with different features developing for different reasons,” says Samuel Mehr, who co-authored the paper with psychologist Max Krasnow. “Our theory raises the possibility that infant-directed song is the starting point for all that.”

Mothers vocalize to their babies “across many, if not all, cultures,” the researches note in the journal Evolution and Human Behavior. Its ubiquity suggests this activity plays a positive role in the parent-child relationship, presumably soothing infants by proving that someone is there and paying attention to them. [Continue reading…]

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New evidence that Lucy, our most famous ancestor, had superstrong arms

The Washington Post reports: In Ethiopia, she is known as “Dinkinesh” — Amharic for “you are marvelous.” It’s an apt name for one of the most complete ancient hominid skeletons ever found, an assemblage of fossilized bones that has given scientists unprecedented insight into the history of humanity.

You probably know her as Lucy.

Discovered in 1974, wedged into a gully in Ethiopia’s Awash Valley, the delicate, diminutive skeleton is both uncannily familiar and alluringly strange. In some ways, the 3.2-million-year-old Australopithecus was a lot like us; her hips, feet and long legs were clearly made for walking. But she also had long arms and dexterous curved fingers, much like modern apes that still swing from the trees.

So, for decades scientists have wondered: Who exactly was Lucy? Was she lumbering and land-bound, like us modern humans? Or did she retain some of the ancient climbing abilities that made her ancestors — and our own — champions of the treetops?

A new study suggests she was a little of both: Though her lower limbs were adapted for bipedalism, she had exceptionally strong arm bones that allowed her to haul herself up branches, researchers reported Wednesday in the journal PLoS One. [Continue reading…]

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Meet the frail, small-brained people who first trekked out of Africa

Science magazine reports: On a promontory high above the sweeping grasslands of the Georgian steppe, a medieval church marks the spot where humans have come and gone along Silk Road trade routes for thousands of years. But 1.77 million years ago, this place was a crossroads for a different set of migrants. Among them were saber-toothed cats, Etruscan wolves, hyenas the size of lions—and early members of the human family.

Here, primitive hominins poked their tiny heads into animal dens to scavenge abandoned kills, fileting meat from the bones of mammoths and wolves with crude stone tools and eating it raw. They stalked deer as the animals drank from an ancient lake and gathered hackberries and nuts from chestnut and walnut trees lining nearby rivers. Sometimes the hominins themselves became the prey, as gnaw marks from big cats or hyenas on their fossilized limb bones now testify.

“Someone rang the dinner bell in gully one,” says geologist Reid Ferring of the University of North Texas in Denton, part of an international team analyzing the site. “Humans and carnivores were eating each other.”

This is the famous site of Dmanisi, Georgia, which offers an unparalleled glimpse into a harsh early chapter in human evolution, when primitive members of our genus Homo struggled to survive in a new land far north of their ancestors’ African home, braving winters without clothes or fire and competing with fierce carnivores for meat. The 4-hectare site has yielded closely packed, beautifully preserved fossils that are the oldest hominins known outside of Africa, including five skulls, about 50 skeletal bones, and an as-yet-unpublished pelvis unearthed 2 years ago. “There’s no other place like it,” says archaeologist Nick Toth of Indiana University in Bloomington. “It’s just this mother lode for one moment in time.”

Until the discovery of the first jawbone at Dmanisi 25 years ago, researchers thought that the first hominins to leave Africa were classic H. erectus (also known as H. ergaster in Africa). These tall, relatively large-brained ancestors of modern humans arose about 1.9 million years ago and soon afterward invented a sophisticated new tool, the hand ax. They were thought to be the first people to migrate out of Africa, making it all the way to Java, at the far end of Asia, as early as 1.6 million years ago. But as the bones and tools from Dmanisi accumulate, a different picture of the earliest migrants is emerging. [Continue reading…]

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Humans aren’t the only primates that can make sharp stone tools

 

The Guardian reports: Monkeys have been observed producing sharp stone flakes that closely resemble the earliest known tools made by our ancient relatives, proving that this ability is not uniquely human.

Previously, modifying stones to create razor-edged fragments was thought to be an activity confined to hominins, the family including early humans and their more primitive cousins. The latest observations re-write this view, showing that monkeys unintentionally produce almost identical artefacts simply by smashing stones together.

The findings put archaeologists on alert that they can no longer assume that stone flakes they discover are linked to the deliberate crafting of tools by early humans as their brains became more sophisticated.

Tomos Proffitt, an archaeologist at the University of Oxford and the study’s lead author, said: “At a very fundamental level – if you’re looking at a very simple flake – if you had a capuchin flake and a human flake they would be the same. It raises really important questions about what level of cognitive complexity is required to produce a sophisticated cutting tool.”

Unlike early humans, the flakes produced by the capuchins were the unintentional byproduct of hammering stones – an activity that the monkeys pursued decisively, but the purpose of which was not clear. Originally scientists thought the behaviour was a flamboyant display of aggression in response to an intruder, but after more extensive observations the monkeys appeared to be seeking out the quartz dust produced by smashing the rocks, possibly because it has a nutritional benefit. [Continue reading…]

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