Why do animals keep evolving into crabs?

May 30, 2023 7:19 AM

Crabby bodies are so evolutionarily favorable, they've evolved at least five different times. So why does this process, known as carcinization, keep happening? (carcinis/zation previously)
posted by Etrigan (43 comments total)

in my day we worked hard, got mortgages, and had kids, but now all Gen Z wants to do is evolve into crabs
posted by entropone at 7:25 AM on May 30, 2023 [51 favorites]

if i could evolve a hard shell and wicked pincers i'd do it too
posted by dis_integration at 7:28 AM on May 30, 2023 [8 favorites]

Genesis 1:27 clearly.
posted by NotAYakk at 7:30 AM on May 30, 2023 [3 favorites]

you ever met a crab with depression
posted by cortex at 7:44 AM on May 30, 2023 [8 favorites]

It’s the scuttling for me
posted by staggernation at 7:45 AM on May 30, 2023 [9 favorites]

Ah, yes: carcinization, from Tumblr.
posted by meese at 7:51 AM on May 30, 2023 [2 favorites]

I should have been a pair of ragged claws
Scuttling across the floors of silent seas.
posted by chavenet at 8:04 AM on May 30, 2023 [16 favorites]

It's almost as if nature is always there asking: Why not Zoidberg?

Why not Zoidberg, indeed.
posted by RonButNotStupid at 8:08 AM on May 30, 2023 [41 favorites]

News bulletin, I refuse to take the medicine
Fuck a thick skin, I got me a exoskeleton
posted by They sucked his brains out! at 8:23 AM on May 30, 2023 [3 favorites]

This comports with my experience. The older I get, the crabbier I get.
posted by The Bellman at 8:24 AM on May 30, 2023 [10 favorites]

for myself, i blame academia
posted by daisystomper at 8:58 AM on May 30, 2023 [1 favorite]

yeah my first thought is "crab people, crab people!!!" from South Park
posted by gkr at 9:22 AM on May 30, 2023

It's worth noting that trees don't exist (phylogenetically)—that is, plants converge on tree-dom the way invertebrates keep turning into crabs. Also, venom seems to have evolved repeatedly over the past 200M years or so, most notably in limbless reptiles (snakes), although we have examples of envenomation using toxin-secreting bacteria—Clostridia botulinum in the saliva of Komodo Dragons, but also whatever the hell it is that makes cat bites so dangerous. And all solitary-hunting mammalian obligate hypercarnivores seem to converge with mustelids (weasels, stoats, otters, etc) in body plan, so it's not unreasonable to suggest that mustelidization is to mammals as carcinization is to crustaceans.

Anyway, I conclude that the most likely sentient life in the far future is a hyperintelligent, venomous, tree-dwelling crab, or possibly a ferret.
posted by cstross at 10:09 AM on May 30, 2023 [32 favorites]

I for one welcome our hyper intelligent venomous arboreal crab-ferret overlords.
posted by The otter lady at 10:13 AM on May 30, 2023 [1 favorite]

Looking forward to your next book, Charlie, Moulting State.
posted by rory at 10:14 AM on May 30, 2023 [10 favorites]

A while back I came across video of a bottom dwelling fish that was using its fins to push food toward its mouth. So carcinization has some value to offer vertebrates too.
posted by ocschwar at 10:23 AM on May 30, 2023

The latest animal to evolve into a crab is the Rust Programming Language
posted by I-Write-Essays at 10:24 AM on May 30, 2023 [9 favorites]

Came for the crab jokes, not disappointed


Now can we move the discussion forward?
posted by gottabefunky at 10:32 AM on May 30, 2023 [1 favorite]

No, only sideways.
posted by Etrigan at 10:43 AM on May 30, 2023 [48 favorites]

Now can we move the discussion forward?

no, only sideways... dangit
posted by taquito sunrise at 10:43 AM on May 30, 2023 [16 favorites]

Convergent evolution! [pincer-bump]
posted by Etrigan at 10:44 AM on May 30, 2023 [19 favorites]

My dog kept evolving into a crab. We'd swat her with a rolled up newspaper until she stopped, but finally she figured out she could just grab it with her claws and wrench it out of our hands. We finally had to take her to a special obedience school. But that worked.
posted by Naberius at 11:03 AM on May 30, 2023 [11 favorites]

Okay, so one thing I noted from the article is that it isn’t really that animals have evolved into crabs five times. Rather, decapod crustaceans have evolved into the crab shape five separate times. So what is it about the crab form that it is the apotheosis of the decapod crustacean body type?
posted by Big Al 8000 at 11:04 AM on May 30, 2023 [3 favorites]

Crabs are delicious. Further proof that god exists and wants us to be happy.
posted by Dysk at 11:09 AM on May 30, 2023

a pincher-clawed ferret would be a terrifying thing (and more so an arboreal one that could drop down on you all unawares!)
posted by supermedusa at 11:12 AM on May 30, 2023 [4 favorites]

But for better or worse, humans won't be turning into crabs anytime soon. "Our body isn't modular like that," Wolfe said.

I'll show you, Wolfe!
posted by heteronym at 11:31 AM on May 30, 2023 [5 favorites]

a pincher-clawed ferret would be a terrifying thing (and more so an arboreal one that could drop down on you all unawares!)

You can protect yourself from drop-crabs by wearing a hat with a built-in bowl containing melted butter.
posted by Greg_Ace at 11:37 AM on May 30, 2023 [12 favorites]

I once had crabs. Does that count?
posted by dances_with_sneetches at 11:38 AM on May 30, 2023 [2 favorites]

I for one welcome our hyper intelligent venomous arboreal crab-ferret overlords.

Sounds like something a hyperintelligent venomous arboreal crab otterlord or otterlady would say.
posted by straight at 12:46 PM on May 30, 2023 [2 favorites]

rory: Looking forward to your next book, Charlie, Moulting State.
Not Rule Ferrety Paw?
posted by k3ninho at 1:01 PM on May 30, 2023 [1 favorite]

So cool.

Crabs previously.
posted by grobstein at 1:23 PM on May 30, 2023

A: Because of their little crabby-bodies!
posted by Mister Moofoo at 1:39 PM on May 30, 2023

I for one welcome our hyper intelligent venomous arboreal crab-ferret overlords.


Rocket Racoon comes pretty damn close.
posted by ocschwar at 1:53 PM on May 30, 2023

> a pincher-clawed ferret would be a terrifying thing (and more so an arboreal one that could drop down on you all unawares!)

Correct, which is why I just added it to the list of critters I need to stat up for a Pathfinder RPG game.
posted by Fiberoptic Zebroid and The Hypnagogic Jerks at 4:55 PM on May 30, 2023 [2 favorites]

Decapodia is the key insight.
posted by aught at 7:05 PM on May 30, 2023 [4 favorites]

Is it true that humans have ten legs? Cuz if so a whole lot of stuff would start making sense.
posted by grobstein at 9:20 PM on May 30, 2023

This is the best thread, thank you all, A+, 100%, no notes
posted by potrzebie at 9:55 PM on May 30, 2023 [2 favorites]

I’m imagining a planet where the dominant animals are crabbish, and they’re all like, isn’t it amazing how quadruped mammals keep evolving into ‘rodents’?
posted by Phanx at 11:16 PM on May 30, 2023 [2 favorites]

Mustelification is the preservation and rediscovery of an ancient platonic form. Not stepping forward blindly into an alien future, but embracing a time-honored tradition.

Reject crab. Retvrn to weasel.
posted by vibratory manner of working at 1:33 AM on May 31, 2023 [6 favorites]

Retvrn to weasel

Incidentally, "Return to weasel" is my new sockpuppet name.
posted by Greg_Ace at 9:59 AM on May 31, 2023 [2 favorites]

don't gnaw on my beak
posted by Greg_Ace at 10:00 AM on May 31, 2023

It was called the Apple Weasel, Greg_Ace, before they renamed the project iCrab.
posted by k3ninho at 11:47 PM on May 31, 2023 [2 favorites]

Don't rubber-band my claws and tell me I have arthritis!
posted by grobstein at 1:51 PM on June 1, 2023