But the real significance of this behavior comes out in courtship and mating. When certain butterflies mate, the males will inseminate the female with a packet called a spermatophore. This 'nuptial gift' contains not only the sperm but a dose of vital nutrients, namely the minerals and proteins that they worked so hard to collect. These compounds are imperative for the healthy development of eggs.
|Tastes like chicken! ...Well, a certain part of the chicken.|
Some females, however, will cheat by mating with multiple males to collect their nuptial gifts, but only producing offspring for the last of the set. Several families have means to combat this, such as a pheromone signature that makes a non-virgin female unattractive to other males, or a mating process that makes it physically impossible for the female to mate twice. Either way, males of many species will do their best to see that their labors of scavenging sweat and other bodily fluids doesn't go to waste.
So remember fellas, having to buy your girlfriend a bouquet or some chocolate every now and then isn't so bad. If you were a spider, you'd probably be eaten by your belle once you'd outlived your usefulness; and if you were a butterfly you'd spend days of your brief life sucking on poop in hopes of having babies that survive infancy.