Penis worms had hermit crab-like defence system 530 million years ago

More than half a billion years ago, tiny penis worms had learned to protect themselves by grabbing and living inside snail-like shells, like hermit crabs do today

Penis worms had hermit crab-like defence system 530 million years ago
More than half a billion years ago, tiny penis worms had learned to protect themselves by grabbing and living inside snail-like shells, like hermit crabs do today