As with humans, snakes have evolved over time. Snakes do not use legs for transportation. Snakes evolved from reptiles, specifically lizards. Over time, lizards’ movement evolved to depend less on legs.
Snakes and lizards belong to the order Squamata. Lizards have fully developed legs that they use to move, while snakes prefer to slither. Scientists debate how and why these species evolved differently. Some snakes still retain the genetic code for leg and foot development.
Ancient snakes had hind limbs up to 70 million years ago, according to recent research. Pythons and boas still have tiny hind leg remnants, which aid in mating.
Why don’t these snakes have legs? Genetic mutations over 100 million years ago turned off the genes responsible for leg development. Let’s explore more about snakes with feet.
The Genetics behind this Mutation
The sonic hedgehog gene (SHH) is responsible for limb development, but it has been damaged over time The SHH gene also plays a role in other essential functions beyond limb development. For example, it also serves as a guide for organs and their positioning in growing animals. The SHH is active in lizards, resulting in legs and feet, whereas it is inactive in snakes.
What is the Exact Difference between Lizards and Snakes?
In Lizards, some genes can be “flipped on and off” throughout their growth period thanks to DNA sequencers called enhancers. A lizard’s four legs develop because the SHH requires the enhancers for proper limb development. In snakes, this enhancer is mostly absent from their DNA That is why a snake with feet is not a common sight.
Snake Feet or Legs? What do snakes have?
A snake with feet is evidence that it descended from lizards, and lizards are known to have feet. So, despite the snake’s lack of a limb, it has toes.
What about Baby Snakes?
According to a study in Current Biology, snake embryos develop limb buds within days. A femur, tibia, and fibula were observed to begin development in embryos of pythons even in such a short period.
Can we call Lizards Snakes without Legs?
Ancestry is the key, but lizards without legs are not snakes. In addition, most lizards have eyelids and external ears, whereas serpents have not. The legs of many “legless” lizards, for example, are tiny vestigial limbs, while snakes have no external appendages at all.
What are Legless Lizards Called?
When most people think about a lizard with no legs, they think about a glass lizard. They’re named because their tails are so easily broken that they fall off. They break into smaller pieces like glass when they are smashed. All the glass lizards had either no legs or only a sliver of what they once had.
Also Read: Which Pastel Ball Python is Right for You to Pet?
How many Legs do Pythons and Boas have?
For identifying and tracking purposes, snakes generally lack legs, although pythons and boas have two spurs on either side of the vent that serves as a remnant pelvic girdle and two legs.
What about Claws?
It is well known that pythons, boas, and kindred snakes have claw-like spurs on either side of their vents, according to Boulenger in “Catalogue of Snakes in the British Museum.”
What does it all mean? Some primitive snakes may be able to produce limbs with just a few genetic changes. Their DNA already contains the necessary components for this to happen; they’d need the appropriate circumstances to set them in motion.
