Six research papers have recently been released describing Australopithecus sediba, the hominid species recently discovered in South Africa. It appears to be a haphazard jumble of modern and primitive features. The Wall St Journal takes up the story:
Deepening the mystery of human origins, researchers Thursday offered the most complete view yet of fossils from a puzzling forerunner of humankind, revealing that these creatures were, from head to heel, a collage of primitive and modern anatomy.
..In six research papers published in Science, an international team described how the hominids had almost-human hands attached to apelike arms, a rib cage that was narrow like an ape’s at the top but more humanlike lower down, and a spine that likely had the same number of vertebrae as a human.
Fossils from this ancient offshoot of the human family tree, called Australopithecus sediba, were discovered in 2008 at Malapa, near Johannesburg, South Africa.
These curious hominids lived about two million years ago in an era that scientists consider the crucible of human evolution, when four or more apelike hominid species struggled for survival in Africa. The new in-depth analysis of their remains highlights the fits and starts of evolution’s early advances in intelligence and mobility, several independent experts said.
“It is hugely significant,” said paleoanthropologist Ian Tattersall of the American Museum of Natural History in New York, who wasn’t involved in the work. “This is a good example of what we see throughout the human fossil record—vigorous experimentation with species thrown out to succeed or fail.”
Taken together, the research, led by Lee Berger of South Africa’s University of the Witwatersrand, comprises a detailed forensic autopsy on what may be the ultimate cold case: what became of six or more of the sediba species that apparently fell to their deaths in the Malapa Cave about 1.97 million years ago. No one knows if they died together or alone. There is no evidence the creatures were killed by animals.
..The sediba fossils encompass the most extensive set of early prehuman remains ever found, the scientists said. So far, they have identified partial skeletons of a male, a female and a juvenile, and remains of several infants of the species, preserved in some instances right down to traces of tartar clinging to their teeth.