Re: 30,000 year old Homo erectus - ajava [1/1]

26 Dec 1996 12:58:18 GMT

Timo Niroma ( wrote:

: The traditional view has it that Homo sapiens left Africa a little over
: 100,000 years ago. However, Homo erectus had left Africa already at
: least a million years ago. The flow of Homo erectus seemed to have
: stopped 700,000 years ago, when the ice ages became more severe. It
: seems evident that Homo sapiens went north-east to nowadays China,
: which it reached about 60,000 years ago. From there they continued to
: Australia most probably 50,000 years ago.

The data aren't good enough to conclude this. Australia, in particular,
seems to have been populated by HSS before 50000 BP. Note also that there
is evidence for relatively large-brained intermediates by 200000 BP. The
Java data suggest that populations of HE lasted until about 30000 BP.

: It seems also evident that at this point Homo sapiens had replaced Homo
: erectus in Africa, in most parts of Asia and Australia. Europe was
: habitated by Homo neanderthalensis, and America was still without human
: population. But at that point, 50,000 years ago, it is very possible
: that there were places in Asia, islands most probably, and possibly
: also in Africa, where there still lived Homo erectus. If the latest
: Homo erectus people found thus far lived some 250,000 years ago, it's
: no proof that there would not be far more later populations. Maybe they
: were small, maybe they were at remote places. Java some 40,000 years
: ago would just be a case in point. Remember that Neanderthals lived in
: Europe at the same time.

: So I think there is no reason to modify the Out of Africa theory. Homo
: erectus was replaced from about 300,000 to 30,000 years ago by Homo
: sapiens both in Africa and Asia. The replacement seems not to have
: included any gene flow, just conquer of a niche by a more able species
: of Homo.

That's not even clear. We have evidence for HSS with modern behavior in
Africa perhaps as early as 200000 BP, and for HSS with a middle
Paleolithic culture in the Near East as late as 70000 BP.

: The article "Latest Homo erectus of Java" by C. C. Swisher III et al.
: in Science 374, 13 Dec 1996, is very profound and careful in its
: Uranium/Thorium analysis. U/Th has previously showed evidence of being
: a fairly accurate chronometer and in this case it has been used very
: carefully and very knowingly.

: So I think we have now a more accurate and believable Out of Africa
: theory. I don't think that there is anything specially sensational or
: odd in the Java case. Interesting and challenging it is.

Harry Erwin, Internet:, Web Page:
49 year old PhD student in computational neuroscience ("how bats do it" 8)
and lecturer for CS 211 (data structures and advanced C++)