Ben Hart and colleagues at the University of California at Davis School of Veterinary Medicine carried out a survey of 3,000 dog owners, with special focus on the canine love of eating faeces.
23% of owners admitted their dog ate poop, and 16% complained that such a habit was frighteningly commonplace.
From their findings, the researchers opined that canine poop eating was a throwback to a vulpine ancestry. Modern day wolves are well known to eat faeces that they find - especially in the vicinity of their dens - in an effort to ward of faecal-borne parasites and diseases.
But Hart et al. went one stage further in their discussions of the evolution of the modern dog. Previous hypotheses centred on the emergence of the domestic dog suggest the novel dog was a scavenger of rubbish discarded by humans between 15 and 20,000 years ago.
The dump provides answers
However, the lack of rubbish and, logically, the abundance of human poop would have tempted the novel dogs to step up their poop-eating habit. This would have served the purpose of greater nourishment for the dogs. Furthermore, their ‘clearing’ of excrement from around settlements would have been appreciated by humans.
Thus, poop eating - which began as a way to ward off diseases - may well have brought dogs fully into favour with ice age people.
The evidence of doggy success is evident today: it is estimated that there are around 1 billion dogs on Earth!
See also: Why your dog stares at you while pooping