Sometime between about 29,000 and 14,000 years ago, hunter-gatherers navigating the icy landscapes of northern Eurasia turned wolves into dogs by feeding them leftover lean meat.
That, at least, is a likely scenario that would benefit both wolves and people, say archaeologist Maria Lahtinen of the Finnish Food Authority in Helsinki and colleagues. In the harsh winters of the Ice Age, when the game hunted by both species was lean and fat-free, trapped animals would provide more protein than humans could safely consume, the researchers conclude on Jan. 7 in Scientific Reports. People could feed on excess lean meat to captured wolf cubs that were raised as pets because the animals would not have the same dietary limitations, the team proposes.
That idea is largely based on inferences from previous research on how ancient hunter-gatherers survived in Arctic environments and new calculations suggesting that, for dietary reasons, Ice Age groups were unable to eat all the lean meat that was hunted. . Although far from the last word on the controversial origins of dogs (SN: 21/05/15), Lahtinen’s group offers a novel insight into how that process could have developed.
Researchers ’calculations assume that, like some Arctic hunter-gatherers today, ancient humans acquired 45 percent of their calories from animal protein. Humans cannot eat a completely carnivorous diet due to the liver’s ability to generate only a portion of our energy needs from protein. Edible plants could be stored for the winter as a source of carbohydrates, but supplies would dwindle as the large annual freeze ran out, scientists suspect. Thus, Ice Age hunter-gatherers probably reached a point where they concentrated on hunting to extract fat marrow and fat from prey bones to meet energy needs, the researchers argue, leaving much lean meat untouched and available as wolf food.
Competition between humans and wolves for prey would have diminished as generations of pet wolves gradually evolved into dogs, according to the team’s hypothesis. The idea is that only then were the most docile canines trained to help people (SN: 21/03/15).