Evolution
New fossils may fit in gap between apes and humans
Two South African skeletons are part of a previously unknown species that may shed light on human evolution
Two skeletons nearly 2 million years old and unearthed in South Africa are part of a previously unknown species that scientists say fits the transition from ancient apes to modern humans.
The fossils bear traits from both lineages, and researchers have named them Australopithecus sediba, meaning “southern ape, wellspring,” to indicate their relation to earlier apelike forms and to features later found in more modern people.
“These fossils give us an extraordinarily detailed look into a new chapter of human evolution and provide a window into a critical period when hominids made the committed change from dependency on life in the trees to life on the ground,” said Lee R. Berger of South Africa’s University of Witwatersrand. “Australopithecus sediba appears to present a mosaic of features demonstrating an animal comfortable in both worlds.”
Berger and colleagues describe the find in Friday’s issue of the journal Science.
Modern humans, known as Homo sapiens, descended over millions of years from earlier groups, such as Australopithecus, the best-known example of which may be the fossil Lucy, who lived about a million years before the newly discovered A. sediba.
Berger said the newly described fossils date between 1.95 million and 1.78 million years ago.
Some have characterized the find as a “missing link,” but that is a concept no longer accepted by science.
“The ‘missing link’ made sense when we could take the earliest fossils and the latest ones and line them up in a row. It was easy back then,” explained Smithsonian Institution paleontologist Richard Potts. But now researchers know there was great diversity of branches in the human family tree rather than a single smooth line.
The two new fossils were found in a pit in what was once a cave, their bones preserved by hardened sediment that buried them in a flood shortly after they died, the researchers said.
One was a female estimated to have been in her late 20s or early 30s and the other was a male age 8 or 9, according to the report. Two more have been found since this discovery, but Berger declined to detail them.
Berger said their features suggest that the transition from earlier groups to the Homo genus occurred in very slow stages.
“We can conclude that this new species shares more derived features with early Homo than any other known australopith species, and thus represents a candidate ancestor for the genus, or a sister group to a close ancestor that persisted for some time after the first appearance of Homo,” he said.
But, Berger said, it isn’t yet Homo because it “doesn’t have the whole package.”
A. sediba could turn out to be a sort of Rosetta stone that helps unlock the secrets of the development of the genus Homo, Berger said, even if it turns out to be a side branch.
According to the researchers, A. sediba had an advanced hip bone and long legs, allowing it to stride like humans, but also had long arms and powerful hands like an ape. Both the female and the juvenile were 1.27 meters tall (about 4 feet 2 inches). The female would have weighed 33 kilograms (about 73 pounds) and the child 27 kilograms (about 60 pounds).
“The brain size of the juvenile was between 420 and 450 cubic centimeters (about 26.5 to 27.5 cubic inches), which is small, but the shape of the brain seems to be more advanced than that of Australopithecines,” the researchers reported. Our human brains are about 73 to 98 cubic inches.
While the skeletons had traits of both genuses, the researchers said they chose to classify them conservatively as Australopithecus, rather than Homo, because of their upper body design and brain size.
Potts, director of the Human Origins Project at the Smithsonian’s National Museum of Natural History, noted that other examples with some Australopithecine and some Homo traits existed as much as a half-million years before A. sediba. This particular combination has not been seen before, he said.
“It’s part of the experimentation of evolution,” said Potts, who was not part of Berger’s research team. Also, he cautioned, because there are only two examples there is no way to know if the gene pool died out or was passed along to others.
Funding for the research was provided by the South African Department of Science and Technology, the South African National Research Foundation, the Institute for Human Evolution, the Palaeontological Scientific Trust, the Andrew W. Mellon Foundation, the AfricaArray Program, the U.S. Diplomatic Mission to South Africa and Sir Richard Branson, the billionaire founder of Virgin Group Ltd.
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Science: http://www.sciencemag.org
“What Darwin Got Wrong”: Taking down the father of evolution
A new book dares to attack the theory of natural selection by using -- surprise! -- science
At this point, the idea of somebody publishing an attack on Charles Darwin isn’t exactly surprising. The 19th-century naturalist, and the man behind the theory of evolution, has never been a particularly popular figure among conservative Christians, and, these days, the anti-Darwin movement is a cottage industry. In the last year, which marked the bicentennial of Darwin’s birth and 150 years since the publication of “The Origin of the Species,” the man was even subjected to the peculiar indignity of an assault by former “Growing Pains” star Kirk Cameron.
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Thomas Rogers is Salon's Arts Editor. More Thomas Rogers.
Creationism vs. atheism: It’s on!
A "revised" edition of Darwin's "The Origin of Species" turns college campuses into three-ring circuses
America’s universities are supposed to be marketplaces of ideas, but last week they looked more like theaters of the absurd, as representatives of an evangelical group descended on an undetermined number of campuses to hand out free copies of Charles Darwin’s “The Origin of Species.” The catch: They used an edition of Darwin’s seminal 1859 text that included an introduction by Ray Comfort, a minister who has made a specialty of arguing for creationism.
Was this stunt shrewd or moronic? From the first it’s been hard to tell. The plan, innocuously named “Origin Into Schools,” was announced this September in a video featuring Kirk Cameron, a former television child star who co-founded a ministry called Living Waters with Comfort. There’s something almost pitiable about the way Cameron crows over the scheme; he truly seems to find it ingenious. He points out that the University of California at Berkeley cannot prevent the action because “their own Web site” dictates that “anyone is free to distribute noncommercial materials in any outdoor area of the campus.” “Besides,” he gleefully adds, “what are they really going to do? Ban ‘The Origin of Species’? That would be big news! Especially when their own bookstore sells it for $29.99!”
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Laura Miller is a senior writer for Salon. She is the author of "The Magician's Book: A Skeptic's Adventures in Narnia" and has a Web site, magiciansbook.com. More Laura Miller.
Coming up next: The super-rich cyborg overclass
Is the next stage in human evolution a great leap forward for the wealthy? Maybe so, if we don't fix healthcare
As if we didn’t have enough to worry about, the blogosphere is buzzing this week over comments made by technology forecaster Paul Saffo in The Sunday Times suggesting that the “super-rich” are well-situated to evolve into a different species from good old homo sapiens.
(But first, a little blogosphere archeology. I was alerted to the story by a link from Mark Thoma to a Discover Magazine blog post titled “Will the Super-Rich Evolve Into a Different Species?” But Discovery attributed Saffo’s comments to reporting by The Guardian while linking instead to a Telegraph story titled “Rich May ‘Evolve Into a Different Species.’” The Telegraph, meanwhile, reported that Saffo’s comments were made to the Sunday Times, whose story had the less sensationalist title “What’s Your Place in the Brave New World?” And after following this trail, the quote marks that the Telegraph placed around “evolve into a different species” seem a trifle suspect, because it’s the Times writer, Dominic Rushe, who uses the word, not Saffo.)
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Andrew Leonard is a staff writer at Salon. On Twitter, @koxinga21. More Andrew Leonard.
Kirk Cameron monkeys with Darwin
The sitcom star and super-Christian is giving away a new version of "On the Origin of Species," and it's got Nazis
Kirk Cameron In November, Charles Darwin’s history-changing “On the Origin of Species” turns 150. And after a century and a half of archaeological discoveries and biological advances lending credence to his evolutionary theories, even Darwin would have to be impressed with the sheer endurance of those who prefer the literal, biblical version of how we all got here. People like ’80s sitcom star-turned-Christian action hero Kirk Cameron.
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Mary Elizabeth Williams is a staff writer for Salon and the author of "Gimme Shelter: My Three Years Searching for the American Dream." Follow her on Twitter: @embeedub. More Mary Elizabeth Williams.
How cooking makes you a man
Anthropologist Richard Wrangham has a provocative theory on human evolution. It starts with food and an open flame
Animals of the genus Homo are defined by their little mouths, large guts, big brains — and appetite for bratwurst. This, at least, is the provocative theory of evolution put forth by Dr. Richard Wrangham in his fascinating new book, “Catching Fire: How Cooking Made Us Human.”
Wrangham, the Ruth B. Moore Professor of Biological Anthropology at Harvard University’s Peabody Museum of Archaeology and Ethnology, began his career studying chimpanzees alongside Jane Goodall, and rose to academic acclaim as a primatologist specializing in the roots of male aggression. Naturally, he tends to think of most scientific questions in relation to chimps. And so it was that a few years ago, while sitting in front of his fireplace preparing a lecture on human evolution, he wondered, “What would it take to turn a chimpanzee-like animal into a human?” The answer, he decided, was in front of him: fire to cook food.
Continue Reading CloseSarah Karnasiewicz is a freelance writer and photographer based in Brooklyn, N.Y. Until recently, she was senior editor at Saveur magazine; prior to that she was deputy Life editor at Salon. She has contributed to the New York Times, the New York Observer and Rolling Stone, among other publications. For more of her work, visit thefastertimes.com/streetfood and Signs and Wonders. More Sarah Karnasiewicz.
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