The Aztecs worshiped the meat of the axolotl, these were found in the Mexican canals and lakes. Today, only a fraction of this aquatic system remains, and it is being contaminated by fertilizers, pesticides, feces, and garbage from Mexico City. Axolotls, like their European cousins, the olms, are neotenic, which means that they reach sexual maturity looking like larvae; retaining its gills and tail. This causes that they do not develop physically, but they regenerate. The axolotl, as it is also known, grow limbs, bones and organs that have been damaged or cut. They are a thousand times more resistant to cancer than mammals. If they survive modern threats long enough for us to understand their immune cells, we could make tremendous advances in numerous medical therapies.