Friday Cephalopod: emerging from the crepuscular slime

Looking at this beautiful (and tasty) critter reminds me of a question I've been meaning to ask:

How to cuttlefish (even more tasty) and the other cephalopods pull off their camoflage routine?

I once saw a demonstration where a cuttlefish actually matched a black and white checkerboard pattern (or came darn close).

In case anyone cares: My favorite way of eating cuttlefish is when the mantle is cut in to rectangles, then scored in a diamond pattern across the inside, then boiled in a nice Chinese broth.

Around my neighborhood you can buy a "seafood medley pack" with tiny, whole squids and octopi, clams, scallops and "krab." Also very tasty.

Crepuscular slime? Evocative. One of my favorite words, although I don't think of slime as being a dawn/dusk kind of thing.

Pretty squid.

It feeds at dusk and dawn, and it uses slime to defend itself.

How to cuttlefish (even more tasty) and the other cephalopods pull off their camoflage routine?

Vertebrates like frogs have chromatophores (spots of color) in their skin that expand and contract in response to neurotransmitters--one of our vert endocrinology labs was to expose chromatophores to various hormones and neurotransmitters. I remember how quickly the large color spots shrank when exposed to epinephrine, for example.

As I understand it, invertebrates do basically the same thing, but have even more mechanisms (muscular, for example) to control their chromatophores than verts do.

Thanks RavenT.

The other thing I remember is how quickly the cuttlefish can make the change.

Perhaps I've said this before, but I think it would be great to genetically engineer humans to put chromatophores into our skin. If you can change you color like batting an eye, then "color" will become irrelevant!

For land dwelling animals, do the chromatophores provide UV protection the way melatonin (correct thing?) does in human skin? See, I have these spots on my body that multiply when exposed to sun, but they really provide very little protection against sunburn. If I had control over my skin color the way cuttlefish do, I'd switch to UV-blocking mode when I went outside, then I might be able to enjoy a day at the beach!

Exactly, Spike! It sounds like we both have great tans; they're just anisotropically distributed is all :).

We studied both melatonin (the hormone involved in sleep cycles) and melanin (dark pigment) in the vert endocrinology lab, but we never explicitly discussed the sun protection in animals from the melanin in the chromatophores, so I can't really answer your question. It stands to reason that they would be adapted to the sun exposure in their environment, but I don't have any specific knowledge to offer.

RavenT,

Thanks for the correction.

I see by your own blog that you are at UW here in Seattle. Perfect place for people that are not sun worshippers! (Except this past week has been quite clear).

Thanks for your help and keep up the good work.

Chekc out http://www.wabio.com/career/career-opp.htm when you are ready to look for employment (or even now, to see what the bio-med industry looks like).

Thanks, Spike--I will definitely check out the link you provided.

That thing is so transitional it's not even funny.

Mmm.... crepuscular slime....the term rolls of the tongue in frothy flavor...

Biotech Combany in India Supplying Jatrobha Curcas Feeds and Tissue culture Saplings of Orchids and Other Cut Flower Varietiess.