From Newsgroup: talk.origins
https://www.sciencedaily.com/releases/2026/07/260725105554.htm
https://pubmed.ncbi.nlm.nih.gov/41734753/
The paper is open access. These researchers are claiming that the two vertebrate eyes evolved from a degenerate single eye spot. The
deuterostome ancestor had two eyes, but the organism evolved to be
stationary and lost it's original eyes and only retained a light
sensitive spot around 600 million years ago. They claim that this is
the reason why the retina of vertebrates is derived from brain cells and
not the skin like other multicellular animals. Amphioxus must retain
this single degenerate eye spot. The vertebrate eye is backwards in
terms of having the retinal support cells in front of the photo
receptors. The mollusc eye seems to have the better design and has the support cells behind the photo receptors. Amphioxus has the tissues of
the eye spot arranged backwards like it's related vertebrate relatives.
These researchers are claiming that the backwards tissue arrangement is
due to where the retinal cells are derived from and the backwards
arrangement of the tissues in the degenerate single eye spot that
amphioxus still has.
Ron Okimoto
--- Synchronet 3.22a-Linux NewsLink 1.2