Them and Us: How Neanderthal predation created modern humans by Danny Vendramini

Author:Danny Vendramini [Vendramini, Danny]
Language: eng
Format: epub
Publisher: Kardoorair Press
Published: 2011-12-25T18:30:00+00:00

The 31,700 year old skull from Goyet Cave in Belgium, which researchers believe may be the earliest known dog.

Unlike the dog, grey wolves have been around for at least 300,000 years489. They have exceptional hearing and sense of smell—and wolf fossils are found in ancient human sites.

The burgeoning science of molecular genetics, which allows species to be traced via their DNA has provided some startling new dates that have a bearing on this issue. In June 1997, a seminal paper ‘Multiple and Ancient Origins of the Domestic Dog’, by a leading expert on the origins of dogs Robert Wayne and others, was published in Science.490 The geneticists analysed mitochondrial DNA taken from 162 wolves at 27 locations around the world.

MITOCHONDRIAL DNA

Mitochondrial DNA (mtDNA) are molecules that act as a kind of fuel cell for the main DNA by converting nutrients into energy that cells can use. In humans, mtDNA is inherited from the mother’s side. Over the last decade or so, geneticists have been able to extract mtDNA from ancient fossils, including human bones.

Because wild dogs can interbreed, the geneticists also included DNA samples from coyotes and jackals. They then compared these sequences with mtDNA from 140 domestic dogs (representing 67 breeds and 5 cross- breeds from Europe, Asia and North America) to determine the degree of genetic variation. The idea was to calculate precisely when dogs first departed from their wolf ancestors. The findings confirmed an earlier hypothesis by the authors, that dogs were descended from wolves.

But the most startling find was yet to come. The DNA analysis traced various dog breeds into several ‘clades’—segments that evolved from common ancestors. Clade 1, for example, “contained representatives of many common breeds as well as ancient breeds such as the dingo, New Guinea singing dog, African basenji, and greyhound”. The scientists then analysed the divergence within each clade. The degree of divergence between wolves and coyotes reveal they separated about one million years ago. But most significantly, according to Wayne and his co-authors, the divergence between the dogs in clade 1 “implies that dogs could have originated as much as 135,000 years ago”.

Although the study warns that such estimates may be inflated slightly by the techniques used, Wayne notes, “the sequence divergence within clade 1 clearly implies an origin more ancient than the 14,000 years before the present suggested by the archaeological record”. When all the factors were considered, Wayne concludes that the mtDNA evidence “suggested that dogs originated more than 100,000 years before the present”.

In effect, the DNA evidence reveals that wolves were first ‘modified’ by contact with humans at least 100,000 years ago, which coincides with the hypothesis that Skhul-Qafzeh humans first raised wolf cubs 100,000–110,000 years ago and used them as guard dogs.

If domesticated wolves and proto-dogs provided humans with this vital protection during those fraught early years, then we probably partly owe our survival as a species to them. That may account for the special bond that exists between humans and dogs. And it would demand a new recognition of the extraordinary role they played in our survival.

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