Watch: Tiny Hydra Rips Its Mouth Open to Eat

March 8, 2016 - Before a hydra can eat its prey, it has to rip itself apart to form a mouth. Scientists had noticed that its mouth disappears after it eats, but until now they had not seen exactly how the mouth actually forms. See it happen in this eye-opening footage.

Read more about this discovery.

VIDEO: Carter and Hyland et al., Biophysical Journal, 2016; Science Photo Library; Sinclair Stammers; London Scientific Films
STILL PHOTOS: Callen Hyland; Paul Zahl, National Geographic Creative