Although slugs are hermaphroditic, each animal equipped with both male
and female reproductive organs, they mate with themselves only if no other
slugs are around. Given a choice, they seek partners with whom to trade
genetic material, a move that, by favoring the passage of chromosomes from
both parents to the offspring, nurtures a healthier pool of slug genes.
The actual exchange of sperm is preceeded by an elaborate courtship
ritual, which supposedly reduces the chance of two individuals of separate
species mating and giving rise to hybrids.
During courtship, two slugs will circle each other ... with both partners engaged in ritualized bouts of lunging, nipping, and sideswiping with their tails. The two slugs may also display their disproportionately large sex organs. The great grey garden slug's penis is nearly half its
The sight of a courting pair of slugs majestically circling one another
... while they solemnly wave their oversized penises overhead puts the
most improbably athletic couples of Pompeii and Khajuraho into a more
appropriate and severely diminished perspective," note researchers C.
David Rollo and William G. Wellington. "Athletic" is an even more
appropriate adjective for great grey garden slugs, which are able to
copulate in midair, suspended by stretchy strands of mucus up to 17 3/4
As courtship progresses, a banana slug pair intertwines ... stimulating
each other for several more hours. Their genital areas swell as the pair
move even closer together. Penetration takes place, then each slug
alternately releases and receives sperm.
Now the slugs must disengage -- a challenge for two animals so amply endowed and thoroughly covered in sticky mucus. After long bouts of writhing and pulling, the pair may resort to ... apophallation. Translated, this means that one slug gnaws off the penis of the other.
Is there an advantage to such odd behavior? Yes, according to Adrian
Forsyth, author of _A Natural History of Sex_. The apophallated slug,
says Forsyth, "cannot regrow his penis and is now obligated to be a female
and forced to offer eggs." ... In other animal species, gigantism has
been a precursor to extinction. Only by submitting to the shears can
banana slugs maintain their inordinate organs.
So there we have it. The slug. Well hung, can fuck for hours suspended by a rope of snot, all to get his dick chewed off in the end. There's a moral in there somewhere...