Self-domesticating

mice suggest some animals tamed themselves without human intervention

From the floppy ears of dogs to the curly tails of pigs, domesticated animals sport a different look than their wild cousins—a look that scientists chalked up to human intervention. Now, a new study of wild mice shows that they, too, can develop signs of domestication—white fur patches and short snouts—with hardly any human influence. The work suggests that the mice are able to tame themselves, and that other animals like dogs may have done the same before they were fully domesticated by humans.

Serendipitously, Lindholm had also been measuring the mice’s heads for another project. And, just like the Siberian foxes, the mice became smaller and their heads shrank—about 3.5% on average. That’s an “exciting” change that suggests self-domestication can occur as a result of natural selection, says Brian Hare, an evolutionary anthropologist at Duke University in Durham, North Carolina, who was not involved in the work.