Why do snakes have traces of leg like structures that are not used for movement?

Snakes have vestigial leg structures, such as pelvic spurs, as remnants of their evolutionary ancestors that had fully developed limbs. These structures are remnants of the genes responsible for limb development, reflecting the evolutionary transition of snakes from lizard-like ancestors. While they no longer serve a significant purpose for movement, these spurs can play a role in mating and defense. Such features illustrate how species can undergo significant anatomical changes while retaining traces of their evolutionary history.