I Had A Girlfriend Like This Once
From the NY Times
:Across the eastern United States, a gruesome ritual is in full swing. The praying mantis and its relative, the Chinese mantis, are in their courtship season. A male mantis approaches a female, flapping his wings and swaying his abdomen. Leaping on her back, he begins to mate. And quite often, she tears off his head.
The female mantis devours the head of the still-mating male and then moves on to the rest of his body. “If you put a pair together and come back later, you’ll just find the wings of the male and no other evidence he was ever there,” said William Brown, an evolutionary biologist at the State University of New York in Fredonia.
Of course, this has been well-known forever, but there is some interesting work going on:Male mantises responded very differently to hungry females and to full ones. They were more eager to approach full ones than hungry ones. When they did approach hungry females, they jumped onto their mates from farther away, possibly to lessen the chance of the female grabbing him.
Dr. Brown and Mr. Lelito also found that male mantises also took longer to jump off hungry females. Females sometimes grab males as they dismount, and so the males may have waited out of caution.