earliest known stone tools
in the strata, its between the BKT-2 tuff and the BKT-3 tuff
just choppers and flakes
Four genii in this period, all existing at the same time in a radiation event:
All adapted to different niches, MUST be specialized to explain this degree of
differentiation. But we don’t understand very well what those differences were.
Kenyanthropus – 3.5mya, not many fossils
Australopithecus – good amount of fossils, changes in dentition, gracile bodied but
with large jaws. At least two species, one in South Africa and one in East Africa
Paranthropus – is a specialist, looks like Darth Vader. Massive sagittal crest, flared
cheeks to anchor huge chewing muscles. Adapted to crushing seeds and chewing
vegetation. Variation within this genus with separate species in South Africa and
Homo habilis – looks a lot like Australopithecines, but have slightly larger brain size.
Are first representatives of our genus.
Can we assume that because Homo habilis has a larger brain size that they
made the first stone tools? Nope.
Association alone doesn’t solve this problem, and it remains unclear exactly
how to solve this tool.
Lokalalei- Turkana, Kenya
can be placed in time, younger than 2.4mya and older than 2.34mya
492 whole flakes
751 broken flakes
13 retouched flakes
the spread of artifacts lets us start to see how the site was set up
by fitting flakes back onto their cores, you eventually find out that there was
a sequence of knapping. They were coming to the site, making stone tools,
and leaving everything behind when done. Taphonomy:
the study of what happens to animal remains between death and fossilization
differential survival of bones
cut marks, chew marks, acid etching from digestion
which bones survive? (vertebrae don’t often survive, as they are spongy,
degrade, and float)
under what conditions do which bones survive?
Hata Member, Middle Awash, Ethiopia 2.5mya: cut marks and hammer stone
marks. There are no stone tools there, which could indicate that the people
had toolkits and took their tools with them.
in a way, H. erectus marks the turning point in human evolution
smaller brain size than modern humans and Neanderthals
distinctive brow ridge, thicker than modern humans and Neanderthals
marks a significant increase in brain size from H. habilis
its brain size is not like a chimpanzee, and not like a modern human, so we
know its cognitively different from both, but archaeologists are still trying to
figure out wtf to do with that information
it remains unclear whether the cognitive changes included language or not
there is a cost to a larger brain, as H. erectus has to offset the energy that goes
towards supporting the brain
H. erectus appears to be inhabiting and exploiting all the niches that the other
genera from the radiation period occupied
This species colonizes new environments
Olduvai Gorge, Tanzania
Excavated by Lewis and Mary Leakey
Gorge cuts into anci