It’s been far too long since I posted any news about squid, but this morning while drinking my coffee and perusing a recent issue of Reviews in Fish Biology and Fisheries, I happened upon an article with a wonderfully grisly title: “Cannibalism in cephalopods”.

Oh yes. Cannibalism is, of course, extremely common in the animal kingdom, as well as in certain precincts of the American financial industries. Marine biologists have long known that squid, octopi and other cephalopods devour each other with gusto. But according to the authors of this paper, nobody had ever done a good survey of the existing literature in this sepulchral field, so they decided to throw it down.

The paper is filled with delightful and ghastly data points, including my favorite two details:

Cannibalism is so common in adult squids that it was assumed that they are unable to maintain their daily consumption without a cannibalistic part in their diet, due to their high metabolic rates … Cephalopods have the capacity to prey on both relatively small and large prey due to the skilfulness of their arms and tentacles as well as the possibility to shred their food with their beaks.

As the paper points out, cannibalism comes in two big flavors — cannibals that eat strangers, and “filial” cannibals that eat their own kin. Squid and octopuses have been observed doing both, but when it comes to filial cannibalism, apparently nobody is sure whether cephalopods are capable of recognizing their own kin:

“Recognition of familiarity in cephalopods is possible, but not certain … and the possible lack of recognition could promote non hetero-cannibalism in cephalopods.”

Brilliant, dextrous, and sociopathically stone cold. When the denizens of the briny deep become finally weary of humanity’s failings, we are, with horrible certainty, doomed.

(That origami picture above comes from the Creative-Commons-Licensed photostream of Joseph Wu!)

(As an aside, to illustrate this entry I originally went to the Creative Commons section of Flickr and eagerly typed the query “cannibal squid” — and found nothing. People! Get on this! I require public-domain photos of squid eating each other. That seems like a reasonable request! If the Internet isn’t good for this, what precisely is it good for?)