Old dog bones teach scientists new trick
It hardly needs to be said that there’s a long evolutionary distance between Banana Joe and wolves.
The Affenpinscher that took best in show at the Westminster Kennel Club Dog Show in February is at least 16,000 years removed from the days of roaming the wild in hunt of prey.
But how old is the domesticated dog?
A close look at a 33,000-year-old dog skull from Siberia may unlock the secret of when the domesticated canid branched away from its wolf ancestors, a team of scientists has found.
The scientists analyzed DNA from the jaw and teeth of the 33,000-year-old dog-like specimen found in the Altai mountains of Siberia, finding it was more closely related to current domestic dogs than to wolves. The study was published Wednesday by PLoS One.
Although much more analysis would need to be done on other specimens, the results suggest a more ancient history of the dog outside of the areas where it is believed to originate: the Middle East and East Asia.
Scientists have long puzzled over when the domesticated dog branched away from its ancestors in the evolutionary tree, and where it happened. DNA analysis has suggested the dog originated in China aound 16,000 years ago, while other analyses supports the Middle East and Europe.
The oldest domesticated dog fossil, the Goyet dog, is 36,000 years old. If the analysis of the Altai Dog specimen holds up, it would be the second-oldest remains of a domesticated dog on record.
The skull was excavated from the Razboinichya Cave in southern Siberia in 1975. It has a shorter, broader snout associated with domestic dogs, but teeth more similar to those of wolves. An earlier report on the specimen, also published in PLoS ONE, suggested it was an “incipient dog” resulting from wolf domestication, but that its lineage was likely disrupted by the climatic and cultural changes of the last ice age.
For the current study, parts of a tooth and jaw were ground to a powder and subjected to DNA analysis, which then was compared with the gene sequences of 72 dogs, 30 wolves and four coyotes, and with 35 prehistoric canid specimens.
The analysis showed 99% similarity to dogs, but no perfect match to existing dogs or wolves. So, there’s some waggle room.
