"National Post"
 August 4, 2001

 Neanderthals, humans not cousins: study
 Researchers dispute conventional wisdom with digital image: Two separate
species

 Joseph Brean
 National Post

 Human beings and neanderthals are distinct species that share little more
than a distant evolutionary ancestor, Swiss researchers say, despite the
widely held belief that the extinct hunter-gatherer with the sloped
forehead was our brute cousin.

 Using specially designed software to reconstruct the face of a
neanderthal child from fossilized bone fragments, Christoph Zollikofer and
Marcia Ponce de Lon showed that the hominids' distinctive face was
written in their genetic code, and not a product of their environment.

 If the two species had intermingled significantly, humans and
neanderthals would display common facial features, Dr. Zollikofer said. A
digital comparison of the neanderthal child with a living human child,
however, revealed exactly the opposite.

 "We don't see any signs of admixture," he said. "We found homogeneity
within each species, and a clear separation between them, irrespective of
age, sex or geographical location. In our view, this says that they are
two separate species."

 In the multi-media laboratory at the Institute for Anthropology in
Zurich, Switzerland, the scientists designed a computer model of a
neanderthal child's skull using bone fragments found at the Devil's Tower
in Gibraltar, Spain, in the 1920s.

 They tried to reconstruct the soft tissue "without too much fantasy," Dr.
Zollikofer said, who presents his conclusions in the current issue of
Nature.

 They devised a computer program to determine points of reference between
the skull and the soft tissue in a living human child, and located the
same points on a computer model of the neanderthal skull.

 Then it was a simple matter of digitally transforming the human skull
into the neanderthal, and applying the same transformation to the soft
tissue in the face of the human, he said. The result was a digital
photograph of a neanderthal.

 Elizabeth Daynes, a Parisian artist, sculpted a statue of the child,
which is on display at the Museum of the Anthropological Institute in
Zurich.

 "Most of what makes a neanderthal or a modern human is already present in
two-year-old kids," Dr. Zollikofer said. These subtle genetic differences
give rise to the vastly different facial structures of the two species, he
explained.

 After the age of two, the face of a neanderthal changes shape in exactly
the same way as a human's does, suggesting that environmental factors play
only a small role in shaping the face, Dr. Zollikofer said.

 Other anthropologists have claimed the genetic differences between the
species are minimal, and sought to explain the neanderthal's unique jaw
and skull structure in light of their eating patterns.

 In neanderthals, "the mid-face looks as if it has been pulled forward,"
Dr. Zollikofer said. The nasal cavities are more inflated, making the
cheeks appear bigger than in modern humans.

 "It looks a little bit chubby in this region, but it is not fat, it is a
different structure of the bone," he said. Neanderthals had bigger eyes
under prominent brow ridges and lacked the bump of the human chin.

 The question whether neanderthals and humans evolved separately or
together has been hotly debated, Dr. Zollikofer said.

 Fossil records have been unearthed of humans and neanderthals living at
the same time in Israel, he said.

 "This is a strong argument that they were parallel offshoots of a common
ancestor."

 But this ancestor is ancient, he added, and lived at least half a million
years ago.

 Neanderthals became extinct 25,000 years ago.

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