Tiny freshwater animals known as hydra must rip open their mouth skin in order to eat, and now new research shows how they manage to do this.
The unusual process involves changes to the hydra's mouth skin cells that allow the creature to stretch and split apart these cells in a dramatic deformation. The findings are published in the latest issue of the Biophysical Journal.
Small World Under the Sea: Photos
"The fact that the cells are able to stretch to accommodate the mouth opening, which is sometimes wider than the body, was really astounding," senior author Eva-Marie Collins said in a press release. "When you watch the shapes of the cells, it looks like even the cell nuclei are deformed."
Collins, who is a biophysicist at the University of California, San Diego, and her team genetically engineered hydra so that the animals' two layers of tissues would light up, revealing how their mouths and bodies work on a cellular level.
Hydra measure less than one half an inch long. They look like a column with a ring of tentacles at the end. In the wild, the other end adheres to a rock or some other kind of surface, keeping the hydra in place while it waits for unsuspecting prey to swim by.