And Then Evolution Said, "Hold My Beer"

[Paleophyte]

This is a thread for those WTF organisms that just shouldn't exist in any sane universe, but evolution produced while drunk, bored, or tripping balls.

Self-Decapitation as a Survival Strategy

Yup, you read that right. A few species of sea slug practice "extreme autotomy", where their heads can shed their entire body. More modest examples of autotomy occur in lizards, starfish, and lobsters that can shed less significant body parts to avoid predators. But Elysia manages to shed its entire body, not to escape predation, the process is too slow for that, but possibly to ditch parasites. The severed head simply crawls off and regenerates the detached body. Normally, that would be a challenge for an organism, not having any way to eat while it tries to rebuild, but Elysia practices kleptoplasty, the fine art of stealing cellular components from the algae that it consumes. It eats algae and steals their chloroplasts, keeping them alive to help nourish it via photosynthesis. So, when the head detaches, it can literally take the off-grid solar option for the few weeks that it takes for its guts to regenerate. One of the creepier aspects is that the headless body continues to wander around for days and will even respond to stimuli until it finally succumbs to starvation. I wish that I'd seen this one in time for Halloween.

Here's a general article on it in Smithsonian Magazine.

And the original research in Current Biology.

[Gawdzilla Sama]

I shed 160 pounds of ugly fat. Haven't heard from her since.