TEMPE, Ariz. Discovery of a nearly intact 3.3 million year-old juvenile skeleton is filling an important gap in understanding the evolution of a species thought to be among the earliest direct ancestors to humans, says William Kimbel, a paleoanthropologist with ASU's Institute of Human Origins. Kimbel is part of the team that studied the skeleton of an approximately three-year-old female Australopithecus afarensis, the same species as the well known Lucy, from Dikika, Ethiopia.
"It's extraordinarily rare to have such a complete skeleton," said Kimbel, science director at the Institute of Human Origins. "It's unprecedented to have such a complete skeleton of a young child."
The researchers describe their discovery and initial analysis of it in "A juvenile early hominin skeleton from Dikika, Ethiopia," in the current issue of Nature (Sept. 21, 2006). The skeleton was discovered by lead author Zeresenay Alemseged, director of the Dikika Research Project and a former postdoctoral researcher at ASU's Institute of Human Origins. Alemseged is now at the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
Other authors of the paper are Fred Spoor, University College London; Rene Bobe, State University of New York at Buffalo; Denis Geraads, National Center for Scientific Research, Paris; Denne Reed, University of Texas at Austin; and Jonathan G. Wynn, University of South Florida.
Alemseged has been carefully preparing the skeleton for the last five years by chipping away sandstone from the fragile bone fragments. He still has several years more work to complete it. The skeletal remains include the skull and jaws with teeth, and parts of the shoulders, spinal column, ribs, right arm, fingers, legs and left foot.
Analysis of the skeleton by Alemseged and his team has shown that its lower body is adapted for bipedal locomotion, like that of adult Australopithecus, while the upper body, especially the scapula
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Arizona State University