[FROM THE BBC]


Ancient 'tool factory' uncovered

The stones throw light on life two million years ago

A 2.34-million-year-old 'tool factory' has been unearthed in Kenya, the
science journal Nature reports.
The team behind the find say it shows that our pre-human ancestors had more
sophisticated technical skills than was previously thought.



Science Correspondent Christine McGourty: "Tool-making is considered a
landmark in intelligence"
The researchers say the tools are from a time when man's ancestors were not
thought to have had the mental or physical ability to fashion them.

The Nature report says the tools were found with bones of fish and mammals
and had probably been used to cut up meat.

Egg shells were also found at the site, indicating that the inhabitants of
the region had a varied diet.

The 'tool factory' could date back to small ape-like pre-humans from before
the development of the Homo evolutionary group.

Helene Roche, an archaeologist at the University of Paris, said: "They were
more elaborate and sophisticated than what we had seen previously or thought
possible for stone tools of this age."

Piecing together the past

The tools, found in northern Kenya's Rift Valley, were sharp flakes
methodically chipped from a single rock.

Archaeologists pieced together more than 2,000 flakes found at the site to
produce about 60 reconstructions of the original stones.

In reporting their finding, the team said two things demonstrate the skill of
the early toolmakers:


New rocks would be tested to see if they produced the required sharp-edge
flakes and would be discarded if they did not.

The tool-makers knew how to chip off each flake so that it left a surface
suitable for producing another flake.
Craig Feibel, a geologist on the team, said: "It's not like they were just
randomly whacking away and knocking off whatever happens to come off."

Homo habilis, a species of pre-humans that lived about two million years ago
may have been the tool makers, it is thought. Australopithecine, another
early hominid, is also a candidate.

[FROM THE BBC]


Friday, January 15, 1999


A taste for meat

The human ancestor ventured out from the trees to the savannah for food

One of the distant relatives of man probably developed a taste for meat much
earlier than thought, according to new research.
Australopithecus africanus, a hominid that lived about three million years
ago, was believed to have eaten a diet much like modern chimpanzees. They
forage mostly in wooded areas for fruits and plant material from trees and
bushes.

Later hominids, on the other hand, looked for food in more open environments
such as grasslands and ate the meat of animals they killed with stone tools.

But after studying the fossilised teeth of Australopithecus, Matt Sponheimer
and Julia Lee-Thorp from the University of Cape Town now think its diet may
have been much more diverse - small mammals that could be caught without
tools may even have been on the menu.

Isotopic analysis



Analysing teeth from Australopithecus africanus revealed a diverse diet
The teeth were subjected to isotopic analysis. This technique relies on the
knowledge that different types - isotopes - of a particular atom exist in the
environment in a specific ratio to each other.

For example, grasses and sedges display a different isotopic ratio of carbon
atoms to that found in the plants typical of woodland areas, like herbs. And
since animals absorb some of the carbon they eat into their teeth, a study of
the isotopic ratio in the enamel should say something about the environment
in which the animals lived.

In the case of Australopithecus, the isotopic content of its teeth is
consistent with a diet that included both the grasses and sedges found on
open savannahs and the woodland plants the creature was supposed to have
dined on exclusively.

Common assumtpions

A pattern of scratching and pitting on the creature's molars also hinted at
meat being a likely source of the unexpected isotopic ratios.

The scientists say the common assumption that our ancestors in the genus Homo
developed their large brains after they began eating the nutrient- and
energy-rich animal foods necessary to fuel the larger brains may now need
reappraisal.

"Our results raise the possibility... that dietary quality improved [through
the consumption of animal foods] before the development of Homo and stone
tools about 2.5 million years ago," writes Matt Sponheimer - also of Rutgers
University in New Brunswick, USA - in the journal Science.