Which ancient fossil snake species provided evidence of retained, albeit small, hind limbs in early snake forms?
Answer
Najash rionegrina
The fossil record offers tangible proof of the stages involved in serpentine evolution. Specifically, ancient fossil snakes like Najash rionegrina are significant because they confirm that limb reduction was a gradual process within the reptilian lineage leading to modern snakes. This particular species retained evidence of small hind limbs. While modern snakes lack external limbs entirely, the existence of Najash rionegrina demonstrates that the ancestors of snakes had undergone only partial limb reduction before the lineage solidified into the wholly limbless forms seen today, preceding the specialization seen in the modern worm snake.
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