What is green and able to regrow lost appendages? Maybe Goku's enemy-friend Namek? Or maybe a crocodile? According to a recent study, in fact, our crocodile friends would be able to regrow lost limbs, as if large snouts and numerous fangs were not already enough to make them decidedly fearsome. This apparently shouldn't surprise us too much. In short, the lizards lose their tails, yet they are not doing so badly.
But it is one thing to see a severed tail grow back in a ten centimeter lizard, another is to observe the same mechanism in a four meter alligator. Still, researchers at the University of Arizona have found that young crocodiles are able to regrow a beautiful massive tail. According to the research team, this scientific discovery would make our alligator friends leap onto the podium of the largest animals capable of regrowing severed parts. Really fascinating.
"Reptiles are the only amniotes that maintain the ability to regenerate their appendages"
The research, according to National Geographic, began in 2017. One day, the biologist Kenro Kusumi, of the university in question, had a rather unusual alligator tail delivered by post. The tip was forked, the anomalous color and some deformities present on the surface made Dr. Kusumi reflect on the possibility that it was a regenerated reptile tail. But the crocodiles weren't able to regrow their limbs… or were they?
In search of answers, a short time later the biologist decided to set up a research team. "What makes this process interesting in an alligator - aside from its size - is that the regrown tail shows signs of both regeneration and wound healing within the same structure," explained Cindy Xu, a university researcher. "The regrowth of cartilage, blood vessels, nerves and scales seems consistent with previous studies on lizard tail regeneration," she added.
Crocodiles like lizards (more or less)
What is missing from the appeal, however, seem to be the skeletal muscles, essential for the movement of a limb. According to the results of the studies conducted by the team, crocodiles are actually able to regrow a limb, but the incredible energy consumption that would serve to regrow all the muscles seems to push crocodiles to "focus on the essential". And it's a big shame, considering how important it is for an alligator to have a tail in motion, between swimming and balance.
"Tissue regrowth is very costly from an energy point of view," continued Dr. Xu. "By employing all your energy to perfectly regrow a structure, you irretrievably divert the same energy from other more essential processes". Discovering that crocodiles are able to regrow a lost limb could open up interesting developments for us humans as well. After all, we too are capable of carrying out tissue regeneration, albeit partial.
The discovery could help us non-reptilians too
Sure, we won't be able to regrow an arm - or tail - but our bodies know how to heal a wound. But what if we too were capable of spectacular feats? "We know that humans - who are unable to regenerate - have the same cells and use the same regeneration pathways that these other animals do," said Dr Jeanne Wilson-Rawls, co-author of the study. “If this very large, long-limbed animal has this ability, how can we take advantage of it? Could we possibly help people who have lost limbs or burn victims who need skin regeneration? ”. These are the questions of science. Could a superhero regeneration be in store for us too?