"The phrase "family bush" doesn't trip off the tongue the way "family tree" does, but anyone talking about human evolution had better get used to it... Two fossils discovered in Kenya suggest that evolution was a lot messier than that. One of the specimens, found just east of Kenya's Lake Turkana, is the upper jaw bone of a habilis from 1.44 million years ago; habilis was thought to have become extinct about 1.6 million years ago... The evidence that Homo habilis and Homo erectus lived at the same time in the Turkana basin makes it "unlikely that Homo erectus evolved from Homo habilis," says Meave Leakey, a lead author of the paper announcing the discovery in tomorrow's issue of the journal Nature... The discoverers are sticking by their guns, and even Tattersall agrees that their conclusion—that erectus and habilis overlapped in time and that habilis was not the direct ancestor of erectus—is probably right. Which leads to perhaps the greatest puzzle of all. Throughout human evolution, several species of ancestors lived at the same time. The most recent, of course, were Neanderthals, which made their last stand in the Iberian peninsula about 35,000 years ago. Then why is Homo sapiens the one and only species of human on the planet today?"
http://www.newsweek.com/2007/08/07/t...ily-shrub.html
"The fossil puts to rest the notion, popular since Darwin's time, that a chimpanzee-like missing link—resembling something between humans and today's apes—would eventually be found at the root of the human family tree... The biggest surprise about Ardipithecus's biology is its bizarre means of moving about. All previously known hominids—members of our ancestral lineage—walked upright on two legs, like us. But Ardi's feet, pelvis, legs, and hands suggest she was a biped on the ground but a quadruped when moving about in the trees."
http://news.nationalgeographic.com/n...s-ramidus.html
"'A lot of people were happy to hypothesize that as you went back, into that first half of human evolution since the last common ancestor, as you found these fossils they'd be increasingly chimpanzee-like,' said Tim D. White, a paleontologist at the University of California, Berkeley, and a leader of the research team. 'We have something getting pretty close to it in time, and it turns out it doesn't look chimpanzee-like; it's an unexpected combination of characteristics, some of which are new in evolution and put this pretty firmly on our side of the family tree and some others that are very primitive.'... "I think it's a siginficant discovery ... and will generate an enormous amount of controversy," said Johanson, anticipating the storm of debate over the coming years as scientists try to understand whether this creature walked on two feet or how to understand its strange mixture of traits. "I think it's very important to say that this supports the long held idea that we did not evolve from things that look like modern apes.""
http://www.boston.com/news/science/a...uman_skeleton/
"Previously, the hominid Homo habilis was thought to have evolved into the more advanced Homo erectus, which evolved into us. Now, habilis and erectus are thought to be sister species that overlapped in time. The new fossil evidence reveals an overlap of about 500,000 years during which Homo habilis and Homo erectus must have co-existed in the Turkana basin area, the region of East Africa where the fossils were unearthed."
http://news.bbc.co.uk/2/hi/science/nature/6937476.stm
"The new estimate supports claims that recently discovered primate fossils, the Millennium man (Orrorin tugenesis) and Sahelanthropus, are not on the human lineage but belong rather to an ancestral lineage from which both humans and chimps evolved. The results are detailed in the February issue of the journal PLoS Genetics. The new estimate fails to square up with previous molecular estimates for the divergence date, not to mention the fossil evidence on hominids, said Ian Tattersall, a paleoanthropologist at the American Museum of Natural History."
http://www.livescience.com/4406-huma...in-pinned.html
"In the 1990s, scientists finally crossed the Lucy divide. In Kenya, Meave G. Leakey of the celebrated fossil-hunting family came up with Australopithecus anamensis, which lived about four million years ago and appeared to be an afarensis precursor. Another discovery by Dr. Leakey challenged the prevailing view that the family tree had a more or less single trunk rising from ape roots to a pinnacle occupied by Homo sapiens. Yet here was evidence that the new species Kenyanthropus platyops co-existed with Lucy’s afarensis kin... Two even earlier specimens are even harder to interpret. One found in Kenya by a French team has been dated to six million years and named Orrorin tugenensis. The teeth and bone pieces are few, though the discoverers think a thigh fragment suggests that the individual was a biped — a walker on two legs... Other challenges arise from human evolution in more recent epochs. Just who were the “little people” found a few years ago in a cave on the island of Flores in Indonesia? The Australian and Indonesian discoverers concluded that one partial skeleton and other bones belonged to a now-extinct separate human species, Homo floresiensis, which lived as recently as 18,000 years ago.""
http://www.nytimes.com/2007/06/26/sc...ewanted=2&_r=1
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