I’ve just finished reading “A Short History of Everything” by Bill Bryson (well worth a read, IMO). In the chapters related to the evolution of man, Bryson highlights some mysteries, for example, there’s a tool factory in Africa which appeared to have been in constant use for around a million years, with sections devoted to repairing existing tools and creating new ones. No fossilised remains have ever been found in or around the area, leading to the mystery of where the workers there lived and died. Another highlighted was a line, stretching from Europe to Asia in a SE direction, west of which humans used tools, but east of which they did not, and apparently nobody is sure why. Another highlighted was the discovery of fossilised bones in Australia (I think they were Homo habilis fossils) dating a lot older than anyone had previously though man had been in Australia, leading to a mystery as to how they got their.
Are these mysteries resolved (all of the above is from my memory of the book, so the descriptions of the “mysteries” probably say more about my memory than Bryson’s research)? Are there any more interesting ones (I appreciate that there could be many)?
The lack of fossils near the “tool factory” does not indicate much. Fossils are pretty rare, in any event, and the paleontologists may have simply not found where most of the bodies ended up, yet. Are you sure that it was “in service” for a million years? Or was the site used, periodically, over a period of a million years? More sporadic use of the site would also reduce the chance of fossils being found while good materials for tools would attract successive settlements at the site. (And if it is the site I’m thinking of, the original occupants might have been Homo habilis from nearly 2.5 million years ago.)
It is also true that there have been recent discoveries in Australia that push back the date of its settlement by humans or proto-humans. This leaves a puzzle, but it only means that we were not looking for “how” they arrived, earlier because we had not thought that they had arrived earlier. A similar process is going on in the Americas, where the conventional date of human settlement had been around 11,000 B.C.E., but we have begun finding human traces that appear to date back almost 12,000 years earlier than that. Before we found the earlier sites, we only considered the Bering land bridge as an access point, because it fit the time frame. With earlier dates, researchers are now looking at other trans-Pacific modes of immigration.
An excellent book on this subject (and far more likely to be accurate than Bryson, who is a great writer but not a scientist) is The Journey of Man: A Genetic Odyssey by Spencer Wells.
A paleontologist friend once told me that looking at preserved remains and determining the nature of the society that produced them is like watching random television channels for five seconds a day for a year, and using your observations to describe modern society. A lot of it is just guesswork, because we only have archaeological evidence for a painfully small proportion of the past.
This year could see the date for earliest human presence in the Americas pushed back to around 50,000 years ago. Currently that announcement is sort of in academic limbo, since it was done as a press release right after the dates were obtained, rather than as a peer-reviewed journal article. I think Goodyear will have published his results by the time the conference mentioned in that article rolls around.
