MISSISSAUGA , Ontario, Sept. 9 (UPI) -- Canadian scientists have discovered lightweight giant male weta insects are most successful at mating by traveling greater distances each night.
Weta include about 70 insect species endemic to the New Zealand archipelago. Some weta are among the world's largest and heaviest insects.
The research by University of Toronto- Mississauga evolutionary biologists Clint Kelly, Luc Bussiere, and Darryl Gwynne suggests being lightweight and having longer legs assists in reproduction. The scientists found males can walk more than 90 meters each night in search of a mate.
Not only do males travel more than twice as far as females, but the scientists found small, long-legged individuals walked even farther, acquired more mates and transferred more spermatophores to females.
"Our findings are a rare example of sexual selection favoring a suite of traits that promote greater mobility in one sex only," said Kelly. "This is exciting because it suggests that sexual selection for smaller, more mobile males could be responsible for some of the impressive sexual difference in body size in this species."
Importantly, however, the phenomenon might also explain why males are smaller than females in some other animals, Kelley said.
The research appears in the journal American Naturalist.
