Beetle's chemical tells mate: 'Not tonight'

When a female "burying beetle" is focused on caring for babies and not making new ones, she releases a chemical signal to her libidinous mate that says in no uncertain terms: "Honey, I'm not in the mood."Scientists described how these females employ an anti-aphrodisiac chemical known as a pheromone during a three-day period critical for raising offspring to tell the male she is temporarily infertile and prevent him from trying to copulate.