Each year, the small South Australian town of Whyalla becomes home to one of the most spectacular underwater events: the spawning of the giant Australian cuttlefish.In an environment where males can outnumber females 10 to one, competition is fierce to pass on one"s genes. In most species, size matters: large, aggressive males fight off their rivals to win the chance to mate. This is seen in cuttlefish as well, with large males known to wrestle one another for dominance in the presence of a female.