Octopus fossils—and their modern-day relatives—are entirely Earth-evolved, but their biology is so bizarre that some people can’t help but wonder… are they even from here?

Check out a few octopuses factslaps:

A genetic enigma – Their DNA is like no other, packed with complexity and strange patterns that puzzle researchers. Octopuses have about 33,000 protein-coding genes, more than humans, who have around 20,000. Their genome is large and intricately organized, rivaling that of mammals in complexity.

Masters of disguise – Color, texture, shape—these sea shapeshifters can become anything.

Deep-sea geniuses – They solve puzzles, use tools, and even escape aquariums like stealthy ninjas.

Some theories suggest they could’ve arrived on Earth via panspermia (life traveling through space on comets), but science hasn’t found proof. Yet.