The sneezing adaptation of the acuo sparked a heated arms-race. Those worms with longer, sharper, and tougher barbs invariably resisted the sneezes. This led to tougher sneezes, longer barbs, tougher sneezes, and so on. The barbs aren't conducive to burrowing, so the worms have to move by jumping with flicks of their muscular tails. Some worms can leap up to a meter at a time in this way. They also secrete hormones to attract other worms to recent kills.
