Barnacles are small crustaceans which begin as free-swimming shrimp-like animals, but spend their adult lives attached permanently to something solid – a rock, a shell, a piece of wood, the bottom of a ship or the head of a whale – filter-feeding from the surrounding water by their legs. It’s not much of a life, but then barnacles aren’t exactly occupying an ecological niche which relishes a challenge.
There’s one big, enormous, huge challenge to being a sessile filter-feeder though: how do you reproduce? You can’t exactly walk around to find and seduce a mate. And though most barnacles are hermaphroditic, self-fertilisation is an ecological dead end in terms of genetic diversity. Evolution frowns on it.
So, since it can’t exactly f*ck itself, what is the barnacle to do? It could release clouds of eggs and sperm into the water, but if it’s anchored to a moving object, or the current is too strong, said eggs and sperm might be too widely dispersed to meet. And then the barnacle’s chances of spreading its genes are, in a word, f*cked.
The barnacle has solved this somewhat vexatious problem by growing the longest penis in the animal kingdom – forty times longer than its body.
So you can imagine these animals, many species of which look like calcium-plated forts, stretching forth their, um...members...and knocking at the doors of their neighbours. “Little prick, little prick, let me in/No by the hair of my chinny chin chin” or something similar.
And now imagine the same thing applied to humans. The act of sex would be, er, a little difficult except across a building. Bedrooms would probably have to be built like shoeboxes. And after intercourse, men would likely have to wrap their flaccid organs round their waists and carry them around like tails.
Have I grossed you out enough yet?