Dog Brains Shrank 5,000 Years Ago, Study Reveals

Research suggests that the brains of dogs started to reduce in size at least 5,000 years ago, offering new insights into canine domestication. Modern dog breeds, village dogs, and dingoes exhibit brains that are, on average, 32% smaller than those of ancient and modern wolves. Specifically, dogs from the Late Neolithic period, approximately 5,000 to 4,500 years ago, had brains that were 46% smaller than contemporary wolves.

However, the study found no evidence of smaller brains in the earliest canines dating back 35,000 and 15,000 years ago, sometimes referred to as 'protodogs.' This challenges the notion that reduced brain size is an immediate hallmark of domestication, suggesting the relationship might have begun more loosely. Researchers theorize that reduced brain size may have been favored by limited food resources, as smaller brains require less energy.

Experts note that while domestication didn't make dogs less intelligent, it allowed them to become exceptionally skilled at reading human cues and communicating. This reorganization associated with smaller brains could have made them more wary of environmental changes, potentially serving as effective 'alarm systems.'