Carcinisation (American English: carcinization) is a form of convergent evolution in which non-crab crustaceans evolve a crab-like body plan. The term was introduced into evolutionary biology by L. A. Borradaile, who described it as “the many attempts of Nature to evolve a crab”.
Everything to crab
https://en.m.wikipedia.org/wiki/Carcinisation
Pretty neat
This one’s my favorite!
reject modernity, return to monkey. Reject monkey, advance to crab.