On 16 May 2001 00:26:49 +0100, rhall at webmail.uvi.edu ("Richard L.
Hall") wrote:
>How many vertebrates lack eye lenses? Fish have them as do all
>tetrapods that I know of. So maybe the answer is zero. There are
>some species that have greatly reduced eyes and presumably greatly
>reduced optic tracts. Still, so many other central systems
>decussate, that it seems unlikely that something like the formation
>of a lens could account for crossed visual pathways.
Yes. Even a pin-hole lens produces image inversion.
Kal