As discussed in comments previously, one of the coolest thing about octopodes and cuttlefish is their ability to camouflage themselves and otherwise control the pigmentation of their skin. An article from today’s New York Times discusses the phenomenon. The creatures certainly have some neat tricks:
Dr. Hanlon has watched octopuses perform what he calls the Moving Rock Trick. They assume the shape of a rock and move in plain sight across the sea floor. But they move no faster than the ripples of light around them, so they never seem to move.
The article also describes forms of visual deception used against other cuttlefish. Apparently, there are situations where a male cuttlefish “disguises its skin to look female, he can sneak up to the guarded female and mate. The sneaky male’s disguise may be so good that the other male may try to guard him as part of his harem.” An impressive and cunning trick, for any species.
Close up of a cuttlefish head, showing the well developed eye
YouTube video of a cuttlefish harassing a diver
Youtube video of a tiny cuttlefish.
YouTube video of cuttlefish hovering about. You can see colour changes and movement.
YouTube video with excellent examples of color and texture modulation.
Youtube video Cuttlefish changing colour and shape
Talks David Gallo: Underwater astonishments
Cuttlefish spot target prey early
By Matt Walker
Before they have even hatched, cuttlefish embryos can peer out of their eggs and spot potential prey.
It is the first time any animal has been shown to learn visual images before they are born.
How Smart Is the Octopus?Bright enough to do the moving-rock trick.
By Carl Zimmer
Aristotle didn’t have a high opinion of the octopus. “The octopus is a stupid creature,” he wrote, “for it will approach a man’s hand if it be lowered in the water.” Twenty-four centuries later, this “stupid” creature is enjoying a much better reputation. YouTube is loaded with evidence of what some might call octopus intelligence. One does an uncanny impression of a flounder. Another mimics coral before darting away from a pushy camera. A third slips its arms around a jar, unscrews it, and dines on the crab inside. Scientific journals publish research papers on octopus learning, octopus personality, octopus memory. Now the octopus has even made it into the pages of the journal Consciousness and Cognition (along with its fellow cephalopods the squid and the cuttlefish). The title: “Cephalopod consciousness: behavioral evidence.”
Boing Boing has a story that demonstrates how clever octopodes are:
Angry bored octopus goes wilding
“Otto the Octopus, a resident of Sea Star Aquarium in Coburg, Germany, is bored because the aquarium’s closed for the winter — so he’s making mischief. First he squirted an overhead light until it shorted out, and now he’s taken to juggling the hermit crabs.
“Once we saw him juggling the hermit crabs in his tank, another time he threw stones against the glass damaging it. And from time to time he completely re-arranges his tank to make it suit his own taste better – much to the distress of his fellow tank inhabitants.” ”
Amusing.
The blanket octopuses, four species of octopus in the Tremoctopus genus, are found in the waters of Australia’s Northern Coast.
The male blanket octopus spends his existence drifting along waiting to meet with a female. If the male meets a female, he fills one of his tentacles with sperm and tears it from his body. He gives this sperm-filled tentacle to the female which she then uses to fertilize her eggs. Afterwards, the female leaves the male, who floats away and dies.
…
An unusual defense mechanism in the species has evolved: blanket octopuses are immune to the poisonous Portuguese man o’ war, whose tentacles the female rips off and uses later for defensive purposes. Also, unlike many other octopuses, the blanket octopus does not use ink to intimidate potential predators, but instead unfurls a large net-like membrane which then spreads out and billows in the water like a cape. This greatly increases the octopus’s apparent size, and is what gives the animal its name.
“The Smithsonian National Zoo just got a Pacific Giant Octopus. (Weeeelll, sort of. It’s a baby, and currently only about three pounds. But it’ll be giant someday, promise.) The little critter doesn’t have a name yet, but he (they think it’s probably a he, maybe) does have a web cam. The camera is set up to capture the octopus at feeding times—11 and 3 Eastern, daily. Which is, coincidentally, right about the time I could use a good cephalopod fix in my day.”
XKCD: Mimic Octopus