# c% ? A9 _2 b. I5 v6 dCOVER The rock pigeon (Columba livia) exhibits spectacular variation among more than 350 different domestic breeds. The adult male Old Dutch capuchine shown here is one of many breeds with a crest of reversed feathers on its head and neck. See page 1063 for a description of the genetic origins of the head crest and the relationships among breeds. For the story behind the cover, go to http://scim.ag/cov6123. Photo: Sydney Stringham7 |3 K+ e3 G! R" W; o' U$ e3 l
" W0 L# Z4 Z1 o3 N/ E& T' r7 \# J 作者: 懵懂干细胞 时间: 2013-3-4 14:25