Every now and then, the Internet "discovers" something you just sort of assumed everyone knew.
Like, for example, the fact pufferfish inflate themselves with water and not air. It seems logical that people would assume that fish – which famously remain underwater when they are not dead – fill up with water when they inflate themselves.
But apparently, vast swathes of the Internet learned their information on pufferfish from the underwater levels in Super Mario.
But this latest discovery is one that is a little more niche, and a lot more interesting. Today's topic of Internet discussion is carcinization, or how everything in nature (well, just crustaceans, thankfully) seems to want to be a crab.
Yep, like tech bros repeatedly trying to invent a new type of transport and accidentally reinventing the bus, evolution seems to keep spitting out animals that look like crabs. First coined as a term in 1916, carcinization was originally defined as "one of the many attempts of nature to evolve a crab".
Convergent evolution is when similar features evolve in species from different periods or regions that have a similar form or function, despite the last common ancestor of the animals or plants not having that particular feature. Think how echolocation has evolved in both whales and bats, and mechanisms for flight evolved in birds, insects, pterosaurs, and bats. (Get your own evolutions, bats).
It happens when animals and plants have to adapt to similar environments or ecological niches and end up with similar solutions. Crab-like forms are thought to have happened independently at least five times in decapod crustaceans, including porcelain crabs, hairy stone crabs, and coconut crabs.
It turns out the crab form is so effective, many crustaceans are getting in on the action.
It seems that people will accept convergent evolution in many species, but they draw the line at carcinization.
Others have embraced our crab overlords, or at least turned them into a meme.
Since you're here and we're talking crabs, we're constantly amazed that people aren't aware of boxer crabs. They have evolved a symbiosis with sea anemones, by which we mean they hold them in their claws like boxing gloves and use them to defend themselves.
If one dies, they merely cut the other one in two to make two again.