 In larvae and aquatic salamanders , the tail is laterally flattened , has dorsal and ventral fins , and undulates from side to side to propel the animal through the water . In the families Ambystomatidae and Salamandridae , the male 's tail , which is larger than that of the female , is used during the amplexus embrace to propel the mating couple to a secluded location . In terrestrial species , the tail moves to counterbalance the animal as it runs , while in the arboreal salamander and other tree @-@ climbing species , it is prehensile . The tail is also used by certain plethodontid salamanders that can jump , to help launch themselves into the air . The tail is used in courtship and as a storage organ for proteins and lipids . It also functions as a defense against predation , when it may be lashed at the attacker or <unk> when grabbed . Unlike frogs , an adult salamander is able to regenerate limbs and its tail when these are lost . 
