“Tis strange – but true; for truth is always strange. Stranger than fiction.”
– Lord Byron, Don Juan (1823)
The previous episode left our Pyractomena larva hanging – literally – doing some aerial pupation, very unusual behavior for a firefly! Forsaking the amphibious wanderings of its snail-eating childhood, the pupa now hangs quietly. But inside, a maelstrom of cellular reorganization and growth is transforming its larval body. In just a few weeks, it will emerge as an adult firefly. At this next stage, our Pyractomena will have only one thing on its mind: sex. And yup – you guessed it: Pyractomena fireflies have strange sexual habits, too!
Most male lightningbugs fly & flash to win females. But after racing to emerge early, Pyractomena borealis males forcibly mate with their child brides! Continue reading
Natural selection is based on the struggle for survival, but sexual selection is driven by the struggle for reproductive opportunity. And sexual selection turns out to be quite a powerful evolutionary force – it’s the reason we can enjoy such melodious birdsong, extravagant peacock tails, gigantic deer antlers, and such spectacular firefly flashes!
We know that fireflies give bioluminescent courtship signals, but firefly sex goes way beyond flashing. While mating, many male fireflies give the female a spermatophore, which is an elaborate, sperm-containing package. This firefly “nuptial gift” represents a hefty male investment that’s entirely home-made: it takes several glands to manufacture each gift. Until recently, though, we’ve been largely in the dark about the composition of these mysterious gifts.