The Hydra are a group of invertebrates (animals that do not have backbones) that look like tiny tubes with tentacles protruding off one end. They grow only about 0.4 inches (10 millimeters) long and eat even tinier aquatic animals AND they seem to be immortal, they can live forever without aging.
So why can’t we? There are several reasons. One of them is the inability of our cells to continually divide. The cells of bacteria seem to be able to divide, and form two daughter cells endlessly. Our cells only seem to be able to divide about 60 times …. so after that time the part of the body that the cells support begins to degenerate (die).
The cell dividing and subsequent regenerating is controlled by our DNA. It tells the body what to do. Over the years our DNA becomes damaged by a variety of things and the instructions for regeneration are lost.
However the hydra survives so maybe that will be a route for researchers to find some answers to the problems we face.