Science
News: Improved radiocarbon techniques suggest that
Neanderthal cave sites may be at least 10 000 years older than
earlier studies have indicated. If so, scientists may also have
to revise their understanding of how and why the early hominids
vanished. In
a
paper published online yesterday in the
Proceedings of the National Academy of Sciences,
Rachel Wood of the Australian National University in Canberra
and colleagues explain that the organic material on which
radiocarbon dating depends can become contaminated with modern
material. To remove possible impurities, Wood's team used new
ultrafiltration methods to reassess bones and other artifacts
found on the Iberian Peninsula, the last known region the
Neanderthals inhabited. However, the number of specimens that
Wood's team was able to test was severely limited because
ultrafiltration relies on well-preserved fossils, which are
rare in warm climates such as those of Spain and
Gibraltar.
