A team of researchers at the University of Florida conducted a new study on pythons and boa constrictors. The research accounts for the snakes’ ability to develop limbs in the past, as well as an embryo mutation in the present. However, there are also snake species which don’t display signs of their ancestors’ genes.
The new study from specialists started from a familiar premise, namely that snakes used to have legs in the early stages of their evolution. This happened approximately one hundred and fifty years ago. There are snake fossils which show that the reptiles didn’t crawl from the beginning. The researchers at the University of Florida wanted to know how the change interfered.
First of all, the scientists observed that some snake species, pythons and boa constrictors among them, show signs of their ancestors’ features. More precisely, these snake species have two little bumps placed around their pelvis. Researchers explain that these are undeveloped limbs and are signs of the legs that the snakes’ ancestors used to have.
The research accounts for a genetic change which occurred in the snakes’ DNA throughout time. There is a special gene, named the sonic hedgehog, which is responsible for limb development. According to the study, all vertebrates possess it. However, things are slightly different with snakes, as some sections of the gene were deleted in the course of their species’ history.
Specialists explain that modern day pythons and boa constrictors still have on their bodies the remains of an ancient femur, as well as a formation resembling a claw. The new study showed that the sonic hedgehog gene appears in the snakes’ embryo. However, since some of its sections are deleted, it doesn’t work properly. Hence the reptiles don’t display fully-grown limbs.
Only some snake species have this feature in their embryo stage. There are other species which do not show any signs of primitive limbs. Researchers can also explain the difference between these two categories of snakes. The genes of the ones that do not display the feature have been even more altered than the DNA of the ones that have the small side bumps.
Previous theories claimed that there was a reason why snakes didn’t have legs. It was because they were meant to be aquatic creatures and swim easily. However, the new findings show that snakes could grow limbs today too if it weren’t for the genetic mutation.
Are you impressed by the ability of pythons and boa constrictors to develop limbs in their embryo stage?
Image courtesy of: Wikipedia