How Pythons Get It On

African rock python. Taken from http://largestfastestsmartest.co.uk/wp-content/uploads/2012/04/juvenile_african_rock_python__koedoesdraai.jpg

I recently learned that pythons have specialized structures called "pelvic spurs," a name that sounds crudely kinky . . . and, admittedly, kind of is. The pelvic spurs are located on the ventral side of the python's body near the tail end, and they look almost like claws that project from between scales. The male python will use his pelvic spurs to tickle the female's scales during mating. Apparently she likes it, according to a study performed by Gillingham and Chambers in 1982; soon after tapping and poking about, the female will allow him to mate with her. I would suggest you read the article yourself if you would like to learn more about the Burmese python mating ritual (http://www.jstor.org/stable/1444292). It is both to-the-point and blush-worthy of any proper snake.

A quick look on Wikipedia will tell you that "Pelvic spurs are the externally visible portion of the vestigial remnants of legs found on each side of the vent in primitive snakes . . ." This is where it would not be wise to consult the Wiki world. Although this was cited from Pough et. al's 1992 book of Herpetology, a quick search of other sources will say that pelvic spurs have absolutely nothing to do with long-gone legs. Although limb remnants can be seen in snake skeletons, the pelvic spurs have no connection to the skeletal structure. Possibly, pelvic spurs are simply modified scales.

Unfortunately,  I cannot find a single reference to pelvic spurs in my own herpetology textbook (Herpetology, 3rd by Vitt and Caldwell). I have not even found a reference to whether female snakes have pelvic spurs, whether or not they use them. A firsthand look at the UMM ball python would be unhelpful to answer this question because he is male.

In sum, pelvic spurs are NOT vestigial legs but ARE a plus with the lady snakes.

Pelvic spurs. (http://upload.wikimedia.org/wikipedia/en/thumb/4/42/Anal_spurs.jpg/250px-Anal_spurs.jpg)