One of the most interesting contemporary tetrapods. This cute thing is an example of a biological feature known as Heterochrony, in which an animal overdevelops (peramorphosis) or underdevelops (paedomorphosis) a structure or even its whole being  by changes on the timing of their development. This feature might be an important evolutionary mechanism and may have the ability to explain evolutionary trends in the fossil record.

(Source: devoureth, via jedinosaurmasterpalaeonprime)