[snip]
It wasn't until 1 million years after Ardi that hominids
like Lucy were able to range extensively into the
savannas and develop the robust premolar and molar
teeth with thick enamel needed to eat hard seeds and
roots. One of these species then started scavenging
and using stone tools to butcher larger mammals for
meat, "paving the way to the evolution and geographic
expansion of Homo, including later elaboration of t
echnology and expansion of the brain," White[who
directs UC Berkeley's Human Evolution Research
Center] said.
White said Ardi, who probably weighed about 110
pounds, had a brain close to the size of today's
chimpanzees — one-fifth that of Homo sapiens —
and a small face. Males and females were about the
same size. The hominid's lack of resemblance to either
chimp or modern humans indicates that the last
common ancestor of apes and humans looked like
neither, he said, and that both lines have evolved
significantly since they split 6 million years ago.
White admits that the relationship between
Ar. ramidus and the Australopithecus fossils the team
has found about 80 meters higher in the strata of the
Ethiopian desert is tentative. Nevertheless, he said Ardi's
species could be the direct ancestor of Lucy's species,
which could be the direct ancestor of modern humans.
Without additional fossil evidence, however, connecting
the individual or species dots is hazardous, White said.
"Ardipithecus ramidus is only known from this one
productive site in Ethiopia," White said. "We hope others
will find more fossils, in particular fossils from the period
of 3 to 5 million years ago, to test this hypothesis of
descent."
[snip]
###
