You know what they say about crabs with big shells.
Big shells, big...scientific discoveries!
One such discovery: why exactly hermit crabs have such large penises.
Evolution is a powerful force of nature, and, in the case of the hermit crab, it was used to give the tiny crustaceans proportionally gigantic male organs.
According to scientists, because hermit crabs hate leaving home.
Hermit crabs are incredibly fond of their shells, which offer them protection and become an integral part of their lives. To have sex, a male and female crab push their openings together and the male ejaculates into the female's shell.
However, to make his...erm...."parts" reach, the male must step at least part way out of his shell.
Loosening the hold on his shell can have potentially fatal consequences for the male crab (just as things were going better than ever)! During the male crabs most vulnerable moment, other hermit crabs have been known to rudely run up and steal his shell.
In a new paper, however, published in Royal Society Open Science, Mark Laidre of Dartmouth College believes he's discovered one way crabs have evolved to prevent this theft.
Put simply, Laidre believes hermit crabs have developed enormous penises so they can have sex without leaving their shell.
"In theory. Longer penises could enable individuals to reach out to sexual partners while simultaneously maintaining a safe grip on their property with the rest of their body, thus safeguarding property against thieves while having sex."
Laidre decided to test his theory by applying a bit of logic. If crabs have been evolving big penises because they don't want to lose their houses, then it stands to reason that the more valuable a species's shell, the bigger the penis of that species?
The results spoke for themselves.
"Species carrying more valuable, more easily stolen property had significantly larger penis size than species carrying less valuable, less easily stolen property, which, in turn, had larger penis size than species carrying no property at all."
Twitter couldn't help but crack a few jokes.
Laidre believes other species may be employing the same method to hang onto their possessions.
If you notice any animals with larger-than-average genitals, remember...they might be protecting something valuable!