Axolotls are famous for their extraordinary ability to regrow entire limbs along with tails, spinal cord tissue, and parts of organs including the heart, brain, lungs, liver, and jaw.

Woah, that's a lot of regeneration.

Mice can regenerate the tips of their digits, and humans can sometimes regrow fingertips if the nailbed remains intact after injury, allowing skin, flesh, and bone to regenerate.

TIL.

Unwritten here is how exactly they go about snipping mouse fingers and axolotl tails off. I hope there's at least anesthetic involved.

In mice, the treatment encouraged bone regrowth in damaged digits and partially restored some regenerative abilities lost when the SP genes were absent.

So, sounds like small steps towards identifying part of the puzzle. Cool discovery, but plenty still to do before we're regrowing mouse arms much less human arms.