Here is a Science News article at:
http://www.sciencenews.org/sn_arc99/5_8_99/fob7.htm
which casts a bit more balance on the recent story about a claimed
Neandertal-Modern Human hybrid.
After examining the evidence, neither Stringer nor Schwartz are convinced
that the skeleton is anything more than an "unusually stocky modern human".
I find Trinkaus argument that the skeleton could not have a squat body due
to Ice Age conditions, because "Southwestern Europe did not get cold enough
to instigate such changes", a bit weak. Has he never heard of *migration*?
Steve
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The Weekly Newsmagazine of Science
Volume 155, Number 19 (May 8, 1999)
[...]
Fossil may expose humanity's hybrid roots
By B. Bower
Last Nov. 28, archaeologists working in Portugal's Lapedo Valley, 90
miles north of Lisbon, chanced upon a child's burial. At first the
researchers, led by Joao Zilhao of the Portuguese Institute of Archaeology
in Lisbon, viewed the 24,500-year-old skeleton as an example of modern
Homo sapiens.
The shallow grave resembled other Late Stone Age human burials in
Europe. A seashell lay among the child's bones, which bore the stains of an
intentionally applied red pigment.
By the time excavation of the skeleton concluded on Jan. 7, however, the
scientists suspected that their find represented something far more
interesting-an anatomical hybrid that could only have appeared so late as a
result of extensive prior interbreeding between humans and Neandertals. H.
sapiens and Neandertals both inhabited southwestern Europe for at least
several thousand years, until around 30,000 years ago.
The Portuguese team called in an authority on Neandertals, Erik Trinkaus
of Washington University in St. Louis, to examine the find. He agreed that
they had uncovered a hybrid kid.
Zilhao announced the discovery at a press conference in Lisbon 2 weeks
ago. Trinkaus described the skeleton last week in Columbus, Ohio, at the
annual meeting of the Paleoanthropology Society. A full description of the
new fossil will appear in Proceedings of the National Academy of Sciences.
"This kid surprised us," Trinkaus says. "The mosaic of anatomical features
tells us that when Neandertals and modern humans met, they regularly
interbred."
Some researchers at the Columbus meeting who saw slides of the new
specimen echoed Trinkaus' view. Others argued either that any
interbreeding was minimal or that the fossil merely represents a stocky
modern human.
Much of the child's skull was crushed, although the scientists recovered
braincase pieces and the lower jaw and teeth. The rest of the skeleton was
largely intact. Tooth development places the child's age at between 3 1/2
and 5 years, Trinkaus notes. Radiocarbon analyses yielded the burial's
estimated age.
Modern human traits observed on the skeleton include a well-formed chin
and relatively small lower arms. But the huge "snowplow" jaw, large front
teeth, short legs, and broad chest betray a Neandertal heritage, Trinkaus
says.
The prehistoric child did not belong to a group of modern humans who
may have evolved squat bodies suited to Ice Age conditions, he asserts.
Southwestern Europe did not get cold enough to instigate such changes, in
his opinion.
Trinkaus suggests that Neandertals and modern humans interbred as
closely related members of the same species, as some subspecies of
baboons and other animals interbreed today.
Scientists who argue that modern humanity arose simultaneously in two or
more parts of the world over at least the past 1 million years support
Trinkaus' interpretation. "The Portuguese find indicates that one
anatomically variable human species inhabited western Europe," contends
Milford H. Wolpoff of the University of Michigan in Ann Arbor. "Human
populations have always interbred."
Christopher B. Stringer of the Natural History Museum in London, a
proponent of a theory of more recent human origins in Africa, disagrees.
The fossil youngster may be an unusually stocky modern human, Stringer
holds. Even if further analysis confirms its hybrid status, he suspects that
prehistoric interbreeding rarely occurred. Numerous fossils of early modern
humans show no signs of Neandertal contacts, Stringer notes.
Another out-of-Africa advocate, Jeffrey H. Schwartz of the University of
Pittsburgh, views the fossil child as a modern human who possibly suffered
growth abnormalities that created a bulky lower body. "I don't see any
evidence of hybridization," Schwartz remarks.
References:
Trinkaus, E. 1999. Pathology and persistence in the Pavlovian:
Paleopathology and mobility of DolnÁ Vestonice 15. Meeting of the
Paleoanthropology Society. April. Columbia, Ohio.
Zilhao, J. 1999. The last Neanderthals: Cultural variability and extinction.
Meeting of the Paleoanthropology Society. April. Columbia, Ohio.
Sources:
Erik Trinkaus Washington University Department of Anthropology
Campus Box 1114 St. Louis, MO 63130
Joao Zilhao Instituto Portugues de Arqueologia Palacio da Ajuda
Ministerio da Cultura P-1300 Lisbon Portugal
1999, Science Service.
[...]
Copyright (c) 1999 Science Service
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"When we consider a human work, we believe we know where the
`intelligence' which fashioned it comes from; but when a living being is
concerned, no one knows or ever knew, neither Darwin nor Epicurus,
neither Leibniz nor Aristotle, neither Einstein nor Parmenides. An act of
faith is necessary to make us adopt one hypothesis rather than another.
Science, which does not accept any credo, or in any case should not,
acknowledges its ignorance, its inability to solve this problem which, we
are certain, exists and has reality. If to determine the origin of information
in a computer is not a false problem, why should the search for the
information contained in cellular nuclei be one?" (Grasse P.-P., "Evolution
of Living Organisms: Evidence for a New Theory of Transformation,"
Academic Press: New York NY, 1977, p2)
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