typhlonectes:

Octopus Eyes Are Crazier Than We Imagined

by Maddie Stone

The latest fascinating cephalopod insights come to us from a
father/son team of researchers at the University of California, Berkeley
and Harvard University, who’ve learned that weirdly-shaped pupils may
allow cephalopods to distinguish colors differently from any other
animals we know of. The discovery is published this week in the Proceedings of the National Academies of Sciences.

Boring animals like humans and birds see color using a combination of
light-receptive cone cells, each of which contains pigments that are
sensitive to a different part of the visual spectrum. It’s only by
combining information from different cone cells that colors can be
properly distinguished. Hence, when a person lacks a particular type of
cone, he’s considered colorblind.

Cephalopods only have a single type of light receptor, which means
they should not be able to distinguish color at all. And yet, many
octopuses, squids and cuttlefish have color-changing skin that’s used
for elaborate camouflage ruses and courtship rituals. Clearly, these
colorblind animals have become masters of color manipulation. How? …

(read more: Gizmodo)

photographs: NOAA,
Roy Caldwell, and Klaus Stiefel