Year in Review: Canine genealogy

18

The ancient lineage of man’s best friend is kind of a tangled mess. But scientists made some progress this year in identifying dogs’ ancestors and in estimating the timeline of canine domestication.

Dogs may have descended from a now-extinct wolf species, Adam Freedman of Harvard and colleagues reported in June (SN: 7/13/13, p. 14). They date dog domestication to between 11,000 and 16,000 years ago, before the rise of agriculture.

But not all the new clues tell the same story. Archaeologists have unearthed fossils from doglike animals in both Europe and Siberia that date to more than 30,000 years ago. And in November, Olaf Thalmann of the University of Turku in Finland and colleagues used DNA from the fossils to trace domestic dogs’ origins to Europe between 18,000 and 32,000 years ago (SN: 12/14/13, p. 6).

In January, though, a team analyzing canine genes proposed that dogs became domesticated about 10,000 years ago. Other geneticists examining dog and wolf DNA have placed dogs’ origin in both the Middle East and East Asia.

Freedman’s work relies on genetic evidence from an Australian dingo, a Basenji, a golden jackal and wolves from Croatia, Israel and China — regions where experts have proposed that domestication occurred. The new data all but rule out modern-day wolves as dogs’ ancestors. Still, the location and timing of dogs’ domestication remain uncertain.

Because Freedman’s and Thalmann’s studies tap into a bigger pool of genetic data than previous work, though, their findings may offer better tools for scientists trying to untangle dogs’ lineage.

See all top science stories of 2013