Raccoons are developing pet-like features, with Scientific American citing a peer-reviewed study that found urban raccoons have shorter snouts than rural ones — an early hallmark of domestication.
The paper, in Frontiers in Zoology, analyzed 19,495 iNaturalist photos and reported a 3.56% reduction in snout length among city raccoons after controlling for climate — a change the authors say matches “domestication syndrome,” the package of traits seen in animals adapting to human life. (RELATED: Video Shows Roughly 100 Hungry Raccoons On Woman’s Front Lawn)
“If you have an animal that lives close to humans, you have to be well-behaved enough,” said study co-author Raffaela Lesch, according to Scientific American. “That selection pressure is quite intense.”
Raccoon, between 1913 and 1917. USA. Artist Harris Ewing. (Photo by Heritage Art/Heritage Images via Getty Images)
Researchers argue that domestication often starts without human breeding programs: animals bold (and calm) enough to work the buffet of our refuse thrive near people, passing along tamer temperaments — and, over generations, subtle anatomical shifts. The raccoon results line up with similar urban changes reported in foxes and mice, the authors note.
Why snouts? Shorter faces, smaller heads, floppy ears and coat depigmentation tend to co-occur when species are selected — naturally or artificially — for tameness. One leading mechanism, the Neural Crest Domestication Syndrome hypothesis, links those changes to shifts in embryonic neural crest cells that influence facial structure and stress response. The raccoon data, the authors write, “stand in support” of that model.
City raccoons aren’t lap pets — yet. But the measurable, population-level change suggests “trash pandas” living alongside people are already moving down the same path wolves once walked toward dogs. The authors say raccoons could become a clean model for watching early domestication unfold in a wild mammal without the confounding hybridization that dogs and cats carry from centuries around humans.
Lesch told Scientific American she wants to test whether city raccoons also show genetic or stress-hormone differences — and to see if the pattern holds for other urban scavengers like armadillos and opossums.