Colorblind Cuttlefish

A reader sent in this intriguing question in response to the previous post on cuttlefish:
"What is there vision like? Do they really see around them clearly enough to have evolved mimicry?"

Researchers Mathger et al. have shown that the animals are actually colorblind but can distinguish objects that contrast from the background environment by as little as 15%. Images from their work are shown below:

Cuttle fish fig 2bmp.bmp

Can you find the cuttlefish in these images from the paper?
Cuttlefish Fig 1.bmp

Cuttlefish also have cells called iridophores and leucophores that reflect the brightness of their environments further helping them to blend in. To read more, visit a website dedicated to the physiology of camouflage in cuttlefish. It really is remarkable that these animals are able to mimic their environments so well.

LM Mathger, A Barbosa, S Miner, RT Hanlon. Color blindness and contrast perception in cuttlefish (Sepia officinalis) determined by a visual sensorimotor assay. Vision Research 46 (2006) 1746-1753.

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