Mild defects in early development could explain physical similarities across species
Ruth Ellison/Flickr (CC BY-NC-SA 2.0)
A group of traits common among domesticated animals may arise when a wandering group of multitasking embryonic cells lose their way, a new theory of domestication proposes.
The wandering cells are neural crest cells, which appear early in development in vertebrate embryos. The cells migrate around the embryo and contribute to the development of many tissues, including cartilage and bone in the face, smooth muscle, pigment cells, parts of the nervous system and the adrenal glands, which control the fight-or-flight response. Mild defects in the cells’ migration or function lead to “domestication syndrome,” three scientists propose in the July Genetics. The syndrome is a cluster of traits often seen in tame mammals including white-spotted coats, floppy ears and juvenile-like faces.
In selecting compliant companions instead of more aggressive members of the same species, humans may have