Dogs have been traveling alongside humans for at least 11,000 years, forming a bond shaped by shared journeys, evolving environments, and cultural exchange, according to two new studies published in Science. The research highlights how dogs, in various forms, traveled with people across continents, gradually adapting and diversifying in ways closely tied to human history.
Scientists analyzed hundreds of ancient dog skulls and genomes, uncovering evidence that challenges the belief that modern dog diversity emerged only in recent centuries through selective breeding.
Instead, findings suggest that both the physical and genetic variety among dogs began developing thousands of years earlier, as humans and their canine companions spread into new regions.
Ancient skulls reveal early physical diversity
A team led by Allowen Evin from the University of Montpellier studied 643 dog and wolf skulls spanning the last 50,000 years. Their work revealed that the first clearly dog-like skulls appeared around 11,000 years ago, during the Holocene epoch, just after the last Ice Age.
Alongside this emergence, a wide range of skull shapes and sizes was already present. Evin explained that this diversity predates modern breed development, indicating early dogs were more varied than previously thought.
Further analysis of 17 Late Pleistocene skulls, some dating back 50,000 years, showed all retained wolf-like features.
This suggests the split between wolves and dogs likely occurred during the Pleistocene period, but noticeable changes in dog anatomy began closer to the Holocene. Some early dogs still carried physical traits of their wolf ancestors even after domestication had started.
Dogs traveled with humans through ancient migrations
Meanwhile, a separate study led by Shao-Jie Zhang at the Kunming Institute of Zoology examined 73 ancient dog genomes from the past 10,000 years, focusing on Eastern Eurasia.
Their genetic data showed multiple shifts in dog ancestry that aligned with human migration patterns, including movements by hunter-gatherers, early farmers and pastoralists. The study found that as people relocated, their dogs often went with them, carrying unique genetic markers across regions.
Interestingly, the research also uncovered mismatches in some regions. In parts of Asia, people with Western Eurasian ancestry were found with dogs linked to Eastern Arctic lineages. Zhang noted this could reflect trade or cultural exchange between groups, where dogs were part of the interaction.
Together, the studies reveal that dogs were not only early companions but also vital participants in the spread of human cultures. Their long, shared history with people continues to shape both species today.
