An interesting study that appears in the February 10th edition of Current Biology examines the role played by a particular protein that causes a dramatic increase in male aggression in squid. This aggression-causing pheromone belongs to a family of proteins found in vertebrates, including humans.
"Squid may have revealed a more direct way of stimulating aggression," says Hanlon (one of the lead researchers). "We doubt that many researchers have thought that contact with molecules in the external world could stimulate such complex and extreme aggressive behavior."
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