Our planet's convoluted history of evolving life has spawned countless weird and wonderful creatures, but none excite evolutionary biologists – or divide taxonomists – quite like crabs.
When researchers attempted to reconcile the evolutionary history of crabs in all their raucous glory just earlier this year, they arrived at the conclusion that the defining features of crabbiness have evolved at least five times in the past 250 million years.
What's more, crabbiness has been lost possibly seven times or more.
This repeated evolution of a crab-like body plan has happened so often it has its own name: carcinization. (And yes, if you lose crabbiness to evolution, it's called decarcinization.)
Frog crabs (Raninidae) are one unusual example. Features of the crab body plan were also lost en route to almost-legless Puerto Rican sand crabs (Emerita portoricensis) and various lop-sided hermit crabs – but then red king crabs regained crabby features at the last evolutionary minute.
Evolution Keeps Making And Unmaking Crabs, And Nobody Knows Why
When researchers attempted to reconcile the evolutionary history of crabs in all their raucous glory just earlier this year, they arrived at the conclusion that the defining features of crabbiness have evolved at least five times in the past 250 million years.
What's more, crabbiness has been lost possibly seven times or more.
This repeated evolution of a crab-like body plan has happened so often it has its own name: carcinization. (And yes, if you lose crabbiness to evolution, it's called decarcinization.)
Frog crabs (Raninidae) are one unusual example. Features of the crab body plan were also lost en route to almost-legless Puerto Rican sand crabs (Emerita portoricensis) and various lop-sided hermit crabs – but then red king crabs regained crabby features at the last evolutionary minute.
Evolution Keeps Making And Unmaking Crabs, And Nobody Knows Why