Digit wrote:I can't recall the location now John but I recall reading sometime ago that HE probably survived as a separate species longer in China than elsewhere and that the last of his kind had a brain capacity within HSS range and that he stood no less high than HSS and the Chinese could not say where HE ended and HSS began.
As HE shows a steady increase in brain size through the ages it suggests to me that they are one and the same species. The difference in brain size between the later HEs and HSS is a lot less than the the difference between the earlier HEs and their later compatriots apparently.
Roy.
There's a few problems with that, not least gene data (from the link Rokcet sent over the other day):
http://discovermagazine.com/1997/sep/thethirdman1220/
By one million years ago, Homo erectus was in China and Asian Georgia. By 500,000 years ago, there were erectus-like populations throughout the Old World, from Germany to the Far East and down into Africa. These creatures were improvements on the original H. erectus, sporting enlarged, 1,200 cubic centimeter brains under their persistently low foreheads and thick skull bones. Some people call this new, improved model archaic Homo sapiens. Others call it advanced Homo erectus, and still others put it into a species of its own, Homo heidelbergensis. In Europe this intermediate type seems to have evolved into the distinctive-looking, bigger-brained Neanderthal. The first fossils recognized as modern Homo sapiens of our own sort, with proper foreheads and protruding chins, showed up in the Middle East around 90,000 years ago.
All the experts agree on the fundamentals of this story. But they disagree on what it all means. The simplest interpretation of the fossils is that all the Homo erectus populations, from Africa to Java, evolved together as a single entity into modern Homo sapiens. By this so-called regional-continuity interpretation, there’s no real distinction between sapiens and erectus, and Homo heidelbergensis is just a vague label for the populations in the middle of this process.
The other leading interpretation is the out-of-Africa theory, which sees human evolution as a series of two or three waves of advancement emanating from Africa. In this view, erectus populations were replaced by a wave of heidelbergensis populations, including their Neanderthal offshoot in Europe. All these were replaced in turn by a wave of fully modern Homo sapiens--with no interbreeding between the old natives and the new immigrants.
The out-of-Africa theory has some shortcomings. The biggest problem with it is that nobody can reliably distinguish all these supposed species--Homo erectus, heidelbergensis, neanderthalensis, and sapiens--from one another. There are a lot of fossils that straddle the lines between them, and no two experts agree on just where one species ends and another starts. But the theory also has some facts on its side.
Several lines of evidence suggest that the genetic differences between human populations today date back no further than some 200,000 years. As many geneticists see it, their data just don’t fit the picture of a gradual, million-year-long evolution of erectus into sapiens throughout the whole Old World. To these researchers, the genetic facts suggest that modern populations (or at least modern genes) spread more recently from a single center, just as the out- of-Africa model would have it.
One piece of paleontological evidence for the out-of-Africa theory is that some archaic Homo populations seem to have lingered beyond their time, alongside more modern-looking people--implying that the two types weren’t interbreeding and therefore must have belonged to different species.
