I will grow my arm? the doctor will probably start thinking that you're not right in the head ... but it is not just you're a fan of the animal and just read that salamanders regenerate their body parts ... and also time and again.
In nature there is quite often the regeneration of the members (the tail of the lizard or the legs of a starfish). When a body part is damaged or must shed to escape a predator just get rid of it and wait for regrowth.
The Queen of regeneration is the salamander. When one of these salamanders lost, for example, a foot, then on the stump as a small lump, called a blastema. The blastema only takes 3 weeks to become fully functional a new leg, a fairly short period if we consider that the animal can live 12 years or more. In a human, that would regenerate a limb by not more than 5 months.
Furthermore, since it takes so little to regenerate their legs, this animalete can regenerate again and again throughout his life. And to not be ugly, unattractive and unappealing to the opposite sex, the salamander not produce scars. Although I had to cut his arm several times over a long period, after 3 weeks you never notice it.