According to a blurb in Science yesterday, researchers have discovered a fossilized fish whose eyes show traces of pigment and also fossilized rods and cones. The existence of the cones suggests that color vision developed at least 300 Ma ago. You may read the full article, which appears in Nature Communications, by following the link from the Science article; you can read it only on screen – a pdf will cost you $32.
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P.S. Yes, I learned about Nature's sharing policy by tracing the link from Science. If you follow the link to the Nature article itself, you get only the abstract.
5 Comments
Scott F · 24 December 2014
300Ma fossil? I can understand traces of pigment. That's just chemicals. But traces of rods and cones? That suggests fossilization at the cellular level. That's pretty amazing.
Palaeonictis · 24 December 2014
There's actually remains of starch found that are 250 million years old.
John Harshman · 24 December 2014
What is the distribution of color vision within extant gnathostomes? Don't they all have at least some? If so, this fossil should be no surprise.
Joe Felsenstein · 25 December 2014
Many nocturnal mammals don't have color vision. And I think they are gnathostomes. But I suspect you meant to ask a different question.
John Harshman · 25 December 2014
Actually, nocturnal mammals do have color vision; it's just that they have only two sorts of cones. And that's derived within amniotes. Mostly, the question is about fish.