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After all can't sit on a rock all day
There's a few folk in this office who use a chair as a rock and seem to be able to sit all day without doing anything
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We'll move back a little further in time to HOMO HABILIS:
1. When and where was H. habilis discovered?
2. Who discovered this species?
3. How long ago did H.habilis live?
4. What is the meaning of this species name?
5. Why was this species placed in the genus Homo and not as an Australopithecene?
1.First discovered in 1960 in the Olduvai Gorge, Tanzania
2. Found by the Leakey team led by Louis and Mary Leakey – this specimen was actually found by an assistant (Jonathan Leakey) and has the number OH7 which is designated as the Type specimen for H.habilis.
3. There is some debate about exactly how long ago this species lived but ranges somewhere from 1.4 million years to just over 2.0 million years ago. H.rudolfensis is the fly in the jam pot here with debate around whether this is a separate species or an early H.habilis. The lower time frame (a 2000 discovery) also puts into question whether H.habilis is actually an ancestor to our leaf browsing friend H.erectus with a specimen of H.erectus being found at 1.55 million years ago.
4. The name was suggested by Raymond Dart and means "handy man" – this was given in 1964 due to the location of Oldowan tools found in the same level. Interestingly enough specimens of Paranthropus bosei were found at the same levels – could they have been using the tools as well?
5. The reasons behind putting this species as Homo and not Australopithecus came from Tobias and van Koenigswald who used three criteria:
Expanded cranial capacity (relative to africanus).
Reduced postcanine tooth size.
The presence of a precision grip (determined from the hand bones present in OH 7), which provides the anatomical basis for tool-making.
However, other factors as mentioned by Klippspringer, Ods and H.erectus also come into play here. Well done to Klippspringer for being first of the mark with a great set of answers and for the contributions of all others as well.
You will note that there is a common thread appearing through each of the discussions – where exactly do each of these species fit into the evolutionary tree. The significant overlaps that are now being found and the wide range if features such as brain size, facial features in the fossils leave enough doubt to ensure that one should not think of human evolution as a perfectly linear progression but something else entirely.
Open for discussion for a few days while I take some leave – I'll be back next Wednesday with another question.