WHEN A FEMALE SQUID DEPOSITS HER EGGS ON THE SEA FLOOR, she also imbues them with a protein that essentially drives male squids crazy – not about her but about the eggs.
Studying longfin squids (Loligo pealeii), Scott F. Cummins and colleagues at universities and research institutions in Australia, Thailand and the United States discovered that the outer tunics of squid eggs are embedded with a protein called Loligo microseminoprotein. Their findings were reported in the journal Current Biology.
Squid egg clusters, consisting of two-inch-long, finger-shaped gelatinous capsules, are deposited on the seafloor, attached to algae or other features. They’re communal, meaning that more than one squid will contribute eggs. Each capsule holds up to 200 eggs. They’re attractive as food for fish and other predators.
DON’T TOUCH! Male squids are drawn to the eggs visually, but touching them – and the protein – has the effect of transforming them into lean, mean fighting machines, ready to take on any other male squids who might get near the eggs. [Editor’s note: I’ve been told anecdotally that squids can become aggressive towards divers who touch the eggs.]
Similar proteins are found in other animals, including mammals, although their function is not clear. This is the first substance found in marine creatures shown to trigger aggression.
Publication: Current Biology, 10 February 2011 10.1016/j.cub.2011.01.038. Background source: Marine Life of the North Atlantic, Andrew Martin.