Pat Shipman in American Scientist:
We all know the adage that dogs are man’s best friend. And we’ve all heard heartwarming stories about dogs who save their owners—waking them during a fire or summoning help after an accident. Anyone who has ever loved a dog knows the amazing, almost inexpressible warmth of a dog’s companionship and devotion. But it just might be that dogs have done much, much more than that for humankind. They may have saved not only individuals but also our whole species, by “domesticating” us while we domesticated them.
One of the classic conundrums in paleoanthropology is why Neandertals went extinct while modern humans survived in the same habitat at the same time. (The phrase “modern humans,” in this context, refers to humans who were anatomically—if not behaviorally—indistinguishable from ourselves.) The two species overlapped in Europe and the Middle East between 45,000 and 35,000 years ago; at the end of that period, Neandertals were in steep decline and modern humans were thriving. What happened?
A stunning study that illuminates this decisive period was recently published inScience by Paul Mellars and Jennifer French of Cambridge University. They argue, based on a meta-analysis of 164 archaeological sites that date to the period when modern humans and Neandertals overlapped in the Dordogne region of southwest France, that the modern-human population grew so rapidly that it overwhelmed Neandertals with its sheer numbers.