Don't underestimate little guys. In the world of procreation, a new record holder has emerged in the longest-sperm category.

The achievement goes not to the elephant, the hippopotamus or even the mighty sperm whale. The winner, researchers say, is a tiny fruit fly called Drosophila bifurca, which produces sperm that are more than 20 times the size of its body.

Scientists say they are not quite sure why the fly produces coiled sperm that stretch out about 2.3 inches. But to devote so much of its energy to make giant sperm, they say, the fly must reap some kind of reproductive advantage.

The fly's sperm, 1,000 times longer than those produced by humans, eclipses the previous record held by another fruit fly, Drosophila hydei, which produces male reproductive cells an inch long. The sperm of a man 6 feet tall, if proportionate to that of the champion fruit fly, would be about 120 feet long.