Body of sea urchin acts as one big eye

[Ian David]

Body of sea urchin acts as one big eye
Sea urchins may use the whole surface of their bodies as compound eyes, scientists now suggest.

Although sea urchins don't have any problems avoiding predators or finding comfortable dark corners to hide in, they don't have eyes. The question then is how they see.

Genetic analysis of sea urchins has revealed they have light-sensitive molecules, mostly in their tube feet and in tiny stalked appendages found in among their spines. As such, "it looks like the entire surface of their bodies are acting as one big eye," said researcher Sönke Johnsen, a marine biologist at Duke University.

Scientists had conjectured the spines of sea urchins might then help them pick out relatively fine visual details by screening out light from off angles. If this proved true, urchins with densely packed spines would have relatively sharp vision.

<snip>

Although sea urchins don't have brains, "it could be their entire nervous system more or less acts as a brain," Johnsen said. "In our case, we vertebrates have nervous systems that are more or less controlled by a central brain, but sea urchins have a pretty diffuse nerve net, where no region looks like a central processing unit as far as we can tell. It's hard to examine their nervous systems, since their nerves are very, very small and the animals are more or less made of rock."

More:
http://www.msnbc.msn.com/id/34612243/ns/technology_and_science-science/


Let's see your compound eyes get you out of THIS! Ummmm... Yummmm!

[xchrom]

1. I still like to eat them. Nt

[dkf]

2. Now that I know I'm eating an eye/brain I find them even less appealing.

Please skip the uni nigiri for me.

Thank you.

[xchrom]

5. Lol -- I'll take you portion and give you

Big thanks!

[Orrex]

3. Oliver Twist sure had some crazy tricks up his sleeve.

Oh wait. A sea urchin.


My mistake.

[Captain Hilts]

4. We don't say 'street urchin' any more, do we? Interesting...

[Nihil]

6. Not since sushi restaurants started to catch on ...

... oh, wait ...
:hide: