鱿鱼发光的皮肤图案可能是密码

This is Scientific American's 60-second Science, I'm Susanne Bard. More than 1,500 feet below the surface of the ocean, it's darker than a moonless night.

But even in this murky world, there's constant activity- including groups of Humboldt squid, each the size of a small adult human, darting around in search of fish.

"You can think of them as little rocket ships. They jet through the water. And they engage in these feeding frenzies. They're always looking out for an opportunity to eat."

Stanford University biologist Ben Burford. He says feeding in a group requires careful navigation. "These animals are cannibalistic; they're pretty aggressive. So there's probably some risk to group living.

We think a lot of the communication they do in these groups helps with that. Like, imagine driving in heavy traffic with a bunch of aggressive drivers, say down in Los Angeles.

Thank goodness you have turn signals and brake lights and horns on your cars, because that prevents a lot of catastrophe from happening." Burford thinks Humboldt squid communicate in the dark ocean by using their own form of signaling.

They do it by turning their bodies into animated message boards. How? Like other cephalopods, they can rapidly change the pigmentation patterns on their skin by contracting and relaxing their muscles.

What's more, their bodies can glow. "They're creating a bioluminescent backlighting for their pigmentation patterns.

So it becomes somewhat like an e-reader, something you can actually read in the dark. They're essentially just, you know, selectively revealing and concealing different parts of a glowing body,

producing these patterns on top of a glowing body." Burford suspected that the squids could be combining different pigmentation patterns to create complex signals.