Monday, February 14, 2005
Tiny creatures called dance flies don't have an ornate tail or much else to signal their sex appeal as, say, peacocks do. So the male shows off his fitness through his largess, bringing a female a big dead fly, for example, so that she can nibble on it while he mates with her. The hidden message: I am big and strong enough to schlep this carcass all over the meadow, and if you mate with me our kids will be big and strong, too.Nothing but an entire dead fly will do for me today. Don't try to fool me with a chocolate rose wrapped in a worthless wisp of silk. Hmph!
Over the years, [the researchers] suspect, a few males decided to heck with lugging along a dead fly to their assignation, and instead bestowed just an insect fragment, wrapped in easily carried silk to make it look bigger. Getting good results, some males began skipping the snack and presenting just a worthless wisp of silk. That way, they got to invest less in sex (less foraging for a nuptial gift) and still reap all the rewards.