Nature is filled with amazing flora and fauna, all with different sets of abilities and unique features. While considered impossible for humans, there are many animals that can regenerate part of their bodies. Sea creatures like starfish and octopuses can regenerate their limbs in case they get hurt or have to decapitate themselves to escape from a difficult situation. Living in the wild, these creatures evolved to adapt to the harsh nature of their surroundings. This is not the case for humans. Many people have to live without their limbs or organs, whether it is due to being born that way or being hurt/experiencing an accident. However, taking inspiration from one such animal, researchers are looking into human limb regeneration. Axolotls, with their unique smiles and frilly gills, have become very popular. But these friendly salamanders are more than just cute faces. Scientists are studying them because they might help us solve a big medical mystery: Can people someday grow back lost body parts, like an arm or a leg? Why Did Researchers Pick Axolotls? In a groundbreaking study published on June 10 in Nature Communications, Monaghan's team utilized genetically engineered axolotls that glow in the dark to better understand this astonishing process. What makes axolotls so special? They have an incredible ability to regrow any part of their body, no matter how old they are. If they lose a leg, they can grow it right back. Even if their heart, lungs, or brain gets hurt, they can fix themselves! This amazing ability makes them champions among animals for their extreme healing powers. One of the long-standing questions in limb regrowth has been how cells "know" precisely which part of the limb to rebuild. For instance, if an axolotl loses its upper arm, it regenerates the entire arm. However, if the injury occurs further down the limb, only the lower arm and hand regrow. Body's Internal GPS The key to this mystery appears to be a small molecule called retinoic acid, a compound related to vitamin A and commonly found in skincare products under the name retinol. This molecule acts like a GPS, providing cells with crucial positional information, guiding them on where they are on the body and what specific part needs to be rebuilt. How Retinoic Acid Directs Regrowth The study's findings were compelling. When axolotls were given a drug that prevented the breakdown of retinoic acid, their limbs regenerated incorrectly, with an upper arm forming where a lower arm should have been. In contrast, axolotls not given the drug regrew their limbs normally. This strongly suggests that retinoic acid precisely instructs cells about their location and what structure to grow. Hope for Human Healing While we are still a long way from growing human limbs, this study is a big step in that direction. The scientists believe this research could eventually help people. We all have the same basic genetic instructions for building limbs that we used when we were developing as babies. The challenge now is to figure out how to turn those same instructions back on later in life, which axolotls can do but humans can't yet. This is one of the oldest and most exciting questions in biology. Thanks to the growing interest in axolotls, especially among kids, these unique animals are helping to advance amazing scientific discoveries. It's quite surprising how popular axolotls have become, showing up everywhere from airports to toy stores.