The real kicker is that the snake has hip vertebrae, which likely allowed the critter to use its legs to dig and crawl. ... Later on, snakes lost their hips, and their hind legs, as they became more specialized to various aquatic and terrestrial lifestyles.

What are snake hips?

: a swing dance with sideward foot twisting and resultant hip wriggling.

Do reptiles have hip bones?

The hip bone is characterized by the great length and forward extension of the ilium. The girdle is connected with the costal element of one vertebra, thus establishing a sacral region of the vertebral column. ... In most reptiles the ilium is joined to two sacral vertebrae.