firefly
2003-04-18 | 9:47 a.m.

I thought this was kind of humorous:

WASHINGTON (Reuters) -- That winking glow of the firefly that brightens summer evenings and sends children scampering with jars is basically a big boast akin to a peacock's elaborate tail, researchers reported on Tuesday.

Male fireflies who mustered up a longer fluorescent flash delivered a bigger "nuptial gift" to their mates -- who in turn produced more baby fireflies, the researchers found.

The study, published in the most recent issue of the journal Behavioral Ecology, shows that the sexual grandstanding seen in animals as diverse as birds, deer and people also extends to the insect world.

"Studying how fireflies ensure that their genes are passed on to the next generation gives us insight into how other organisms, including humans, act," said Sara Lewis, an associate professor of biology at Tufts University in Boston, who led the study.

"Pretty much all they do once they turn into adults is reproduce. Most other things also eat. Some organisms also watch TV. But there aren't any distractions from sex for fireflies."

Fireflies live as larvae for two years. "The larval stage is devoted entirely to stuffing their mouths. They eat and grow, eat and grow for two years," Lewis said.

Then they emerge from underground to spend two glorious weeks courting and mating, before they basically starve to death, she said.

A different flash

Each species of firefly has a slightly different flash that translates roughly into a dialect. But there are differences within species, too.

Lewis and colleagues noticed that some firefly males have a longer flash. They watched carefully and found those with the longer signals seemed to have more success mating.

In turn, the females they mated with produced more offspring.

A closer looked showed that the longer-signaling males were not just idly boasting.

"What's really new is the link between the length of male signaling and the nutrient package the male provides," Lewis said, referring to a spermatophore.

"(The spermatophore's) nickname is 'a nuptial gift.' These are basically like nutrients that the males provide to females at mating. In the case of fireflies it is a very, very fancy package that contains sperm and it contains ... proteins that are transferred to the female and later incorporated into the female's eggs," she said.

"You can kind of think of it as child support."

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