Lizards for example can often replace their tails, but the replacement tails are missing vertebrae. Another feature of the axolotl is that it can regenerate missing structures for its entire life. Humans for example have been documented to replace the very distal tips of their fingers. This ability is documented to work best in children, but persists in a less perfect form throughout life. Finger tip amputations that are sutured shut with mature skin will never regenerate.
Most animals show some regenerative ability early in life, but lose that ability as they age.
Part of the challenge for human regeneration research then is to learn how to take advantage of tendencies which we already have. To go back to the Regeneration page click here. To go back to the Leg Lab Home page click here. To go to the Axolotl FAQ's page click here.