Evolution is not tidy

And our family tree has many dead branches:

WASHINGTON - Surprising research based on two African fossils suggests our family tree is more like a wayward bush with stubby branches, challenging what had been common thinking on how early humans evolved.

The discovery by Meave Leakey, a member of a famous family of paleontologists, shows that two species of early human ancestors lived at the same time in Kenya. That pokes holes in the chief theory of man's early evolution — that one of those species evolved from the other.

And it further discredits that iconic illustration of human evolution that begins with a knuckle-dragging ape and ends with a briefcase-carrying man.

The old theory is that the first and oldest species in our family tree, Homo habilis, evolved into Homo erectus, which then became human, Homo sapiens. But Leakey's find suggests those two earlier species lived side-by-side about 1.5 million years ago in parts of Kenya for at least half a million years. She and her research colleagues report the discovery in a paper published in Thursday's journal Nature.

The paper is based on fossilized bones found in 2000. The complete skull of Homo erectus was found within walking distance of an upper jaw of Homo habilis, and both dated from the same general time period. That makes it unlikely that Homo erectus evolved from Homo habilis, researchers said.

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Overall what it paints for human evolution is a "chaotic kind of looking evolutionary tree rather than this heroic march that you see with the cartoons of an early ancestor evolving into some intermediate and eventually unto us," Spoor said in a phone interview from a field office of the Koobi Fora Research Project in northern Kenya.

'Hobbit' race real

JAKARTA: The 18,000yr-old skull and other remains of a small hominid found in the island of Flores, Indonesia belong to a species new to science, researchers concluded after months of study.

Scientists belonging to the Florida State University had found the fossils in 2003, in a limestone cave on the Indonesian island. The find was labeled LB1 but nick-named 'Hobbit' because of its unusual features and likely resemblance to the dwarf-like creature from the J. R. R. Tolkien trilogy 'Lord of the Rings'.

The features had led the FU team to believe they had the remains of an as-yet-undiscovered human species. Other scientists argued that it was an ordinary ancient human who had probably suffered microcephalia – a rare pathological condition where the head is disproportionately small and usually accompanied by mental retardation.

Lead researcher and paleoneurologist Prof. Dean Falk said his team was now “absolutely convinced” that their find was indeed of a new human species. The scientists have labeled it as Homo Floresiensis

Now after more than two years of analysis, the team reverted to their first hypothesis that the remains belonged to a species new to science. In their study, the scientists analyzed several endocasts – computer-generated impressions of the brain structure taken from the hollow within the skulls. The endocasts included 19 of modern humans nine of whom were microcephalic; one belonged to a modern human dwarf of a similar height as LB1.