Newt

Like all members of the order Caudata, newts are characterised by a frog-like body with four equal sized limbs and a distinct tail. Aquatic larvae have true teeth on both upper and lower jaws, and external gills. They have the ability to regenerate limbs, eyes, spinal cords, hearts, intestines, and upper and lower jaws. Recently it was discovered that the Japanese fire belly newt can regenerate its eye lens 18 times over a period of 16 years and retain its structural and functional properties.] The cells at the site of the injury have the ability to de-differentiate, reproduce rapidly, and differentiate again to create a new limb or organ. One theory is that the de-differentiated cells are related to tumour cells since chemicals which produce tumours in other animals will produce additional limbs in newts.