Giant and colossal squids can be more than 40 feet long, if you measure all the way out to the tip of their two long feeding tentacles. But it's their eyes that are truly huge — the size of basketballs.
Now, scientists say these squids may have the biggest eyes in the animal kingdom because they need to detect a major predator, the sperm whale, as it moves toward them through the underwater darkness.
"It's always been a vexing question, of why they have such large eyes," says Roger Hanlon, a biologist at the Marine Biological Laboratory in Woods Hole, Mass. "Yes, the body is large, but the eyes are enormous."
