This one is new to me and it seems almost unbelievable. Apparently, there are three types of fish that work together to catch prey. Ah, but it's even stranger than that.
The roving coralgrouper, a predator fish of the tropical reef, uses sign language to advise fellow hunters of hiding prey.The coralgrouper works with the giant moray eel and the Napoleon wrasse to capture prey. Apparently, the coralgrouper is the instigator. Here's how it works:
The grouper has "burst speed" to capture prey in open water, while the eel can slide into crevices where small fish lurk and the wrasse has powerful extendable jaws that can suck out prey from a hole or smash the reef around it.I would not have thought this possible yet this study confirms the behavior. It's amazing. Once again, we learn that non-human creatures engage in complex behavior. I say it all the time: the difference between us and other creatures is a matter of degree, not a grand change in categories. We are not the only intelligent creatures on this planet. We're just smarter than the other creatures. (At least, that's the working supposition.)
The grouper has two signals it uses in these hunts, according to the paper.
The first is a "high frequency shimmy," or a kind of body shake, that it performs in front of the moray as a general invitation to join it in a chase.
The second is specific, or "referential."
It is a headstand, which the grouper performs vertically and head-down, indicating to the moray or the wrasse where a prey is hiding or where it was last seen.