The weirdly cute axolotl amphibian can regrow entire lost limbs. So you might be thinking, why can't humans do the same?
Surprisingly, we have a lot more in common with axolotls than previously thought. Long ago, humans shared a common ancestor with the axolotl, which means we share several important genes with the amphibian. The difference is, humans use these exact same genes differently than the axolotl, causing humans to scar instead of re-growing a limb.
Scientists are now trying to understand how the axolotl uses those communal genes to generate limbs instead of scar tissue. If they succeed in underpinning the process behind axolotl limb regeneration, it could lead to unprecedented progress in the new field of human limb regeneration.
*Edit: In the original version of the article, the salamander was spelled "axototl." We appologise for any confusion this may have caused.