http://www.youtube.com/watch?v=TeeIxKf8_do&feature=player_embedded Yesterday we reported on a new study that showed shining a laser on certain neurons in mice brains could make them angry and aggressive. But with squid, you don't need a laser to make the males get mean. All you need is to expose them to a particular chemical. From DISCOVER blogger Ed Yong:
In a flash, schools of male longfin squid can turn from peaceful gatherings to violent mobs. One minute, individuals are swimming together in peace; the next, they’re attacking one another. The males give chase, ramming each other in the sides and grappling with their tentacles.
These sudden bouts of violence are the doing of the female squid. Males are attracted to the sight of eggs, and females lace the eggs with a chemical that transforms the males into aggressive brutes.
For plenty more about how this chemical whips the males into an angry frenzy—and why—check out the rest of Ed's post at Not Exactly Rocket Science
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