| uvs is rare in seabirds. | ultraviolet-sensitive vision (uvs), believed to have evolved from an ancestral state of violet-sensitive vision (vs), is widespread among terrestrial birds, where it is thought to play a role in orientation, foraging, and sexual selection. less is known, however, about the distribution and significance of uvs in seabirds. to date uvs has been definitively demonstrated only in two families (laridae and sternidae), although indirect evidence has been used to argue for a more widespread occurrence. ... | 2011 | 21527267 |