Inside the mouth of a hydra

EarthzineEarth Observation

Hydra is a genus of tiny freshwater animals that catch and sting prey using a ring of tentacles. But before a hydra can eat, it has to rip its own skin apart just to open its mouth. Scientists reporting March 8 in Biophysical Journal now illustrate the biomechanics of this process for the first time and find that a hydra’s cells stretch to split apart in a dramatic deformation.