domingo, 5 de abril de 2015

Ancient Homo fossils found in Kenya

Finds add to skeletal diversity of early members of human genus

ST. LOUIS — Researchers have discovered fossils of three ancient members of the human genus, Homo, in East Africa. These finds add to an emerging picture of early Homo as an upright, relatively big-brained African crowd that included different species and body types.

In 2012 and 2013, a team led by Meave Leakey of Stony Brook University in New York unearthed all but one of the teeth from the lower jaw of an adult. The researchers estimate that the hominid lived about 2 million years ago based on previous dating of soil layers there. Another 2-million-year-old adult find consists of pieces of arm bones, a shoulder blade and an S-shaped, humanlike collar bone. A third adult specimen, from about 1.85 million years ago, includes partial arm bones and a nearly complete right foot. All were found in Kenya.

The ancient teeth, which feature one of the largest canines of any ancient Homo find, probably come from a member of Homo habilis, an analysis led by Stony Brook’s William Jungers finds. Junger’s Stony Brook colleague Deming Yang presented the analysis March 27 at a meeting of the American Association of Physical Anthropologists.

Junger’s team says the two other finds may belong to Homo erectus. The 1.85-million-year-old fossils resemble those of 1.77-million-year-old fossils of H. erectus found in West Asia, Yang said. Analyses of a small, nearly complete foot from the 1.85-million-year-old Kenyan finds suggest that this individual stood only about 4 feet, 7 inches tall. Bruce Bower / sciencenews.org