Ancient Worms That Built The Ocean Floor

Pterobranchs are tiny, tube-dwelling creatures that were once dominant ocean life forms. While only a handful of species survive today, their ancestors shaped prehistoric seas for over 500 million years.

These curious animals live inside complex, self-made structures on the seafloor, trapping passing plankton with delicate, feathery tentacles. Though they look like simple worms, they are actually distant evolutionary relatives of vertebrates. While they remain rare today, the fossil record shows they were incredibly diverse during the Cambrian period. They offer a rare glimpse into the complex marine ecosystems that thrived long before the age of dinosaurs.