The secret to climbing…With no legs!

Ontario is home to 17 species of snakes, some swim, some burrow, and some climb. Ever wondered how animals with no legs can be great climbers? According to a study by Bruce Jayne in the Journal of Experimental Biology, turns out it’s all in the roundness of their bodies!

Using Boa constrictors, Corn snakes, and Brown Tree snakes, Jayne and his students compared their climbing abilities and body shapes to determine how different snakes climb artificial branches with varying degrees of roughness.


Bruce Jayne watches a Brown Tree snake climb an artificial branch in his lab (photo:

Jayne noted that the Brown Tree snake has very distinct “keels” on the sides of its stomach, its cross section is shaped like a loaf of bread. The snakes use these keels to push against even the smallest irregularities in the climbing surface, allowing them to climb up almost smooth surfaces. The Corn snakes have smaller keels, and are still pretty good climbers but have trouble with the more smooth climbing surfaces. Their climbing ability on textured surfaces is still better than the Boa constrictor though, which has the roundest body.


Snake body shapes (photo:

The original article from can be found HERE

In Ontario, The Gray Ratsnake and Eastern Foxsnake are shaped like a loaf of bread, which facilitates their amazing ability to climb trees and other structures. On the other hand, some of our more round species, like Gartersnakes or Hog-nosed Snakes, are much more suited to life on the ground. Next time you see a snake, take a look at its body shape and see if you can figure out what type of climber it is!


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