Snakes! Where are their arms and legs? It’s not ok! Over 100 million years ago, snakes did have four appendages, and then evolution stepped in to turn the reptiles into the creepy, slithering freak show that they are today. Now, researchers believe they’ve isolated what caused this change.
Two separate groups of scientists have come to similar conclusions about a mutation in what’s known as “the Sonic hedgehog gene.” Previously, scientists found that the gene played a role in determining leg size in lizards. This led them to believe that it is also important to snakes’ biology.