For most people, getting close to a snake’s teeth would be a terrifying prospect. But for herpetologist Bill Ryerson, it’s an integral part of his job. Ryerson has been studying the teeth of 13 snake species. He discovered that their teeth dictate whether the snakes are ‘strikers’ or ‘lungers.’
More than fangs
Teeth give a fascinating insight into how snakes attack their prey. Previous research has focused solely on snake fangs and not their other teeth.
“I think the other teeth have been overlooked for a few reasons. First was that because venom is such an interesting development for vertebrates, the fangs naturally drew a lot of attention. The second is that the differences in the non-fang teeth are not as obvious at first glance,” Ryerson told IFLScience.
First, Ryerson took CT scans of 70 snakes belonging to 13 species to look at the morphology of their teeth. Then he captured slow-motion footage of them attacking dead rats. He would wiggle the dead rats in front of them and wait for them to speed towards it. There were two distinct ways that the snakes attacked their prey. One group attacked from above at a speed of 2.7 meters per second. Ryerson named these ‘strikers.’ The second group is ‘lungers’, who attack straight on at a slower pace of 1.5 meters per second.
The snakes in each group shared similarities in their tooth morphology. The strikers have longer, narrower teeth in the front of their lower jaw but short, broad teeth at the back. Lungers have shorter and broader teeth that are slightly curved along their bottom jaw.
Ryerson explained how these differences relate to each style of attack.
Pivot point versus curved grip
“The main difference between the two groups is that strikers have very narrow, upright teeth in their lower jaws, related to how that part makes first contact and acts as a pivot point for the rest of the head to rotate over. The lungers have shorter, more curved teeth that work to grip the prey so it can’t escape. They typically aren’t venomous and don’t use constriction,” Ryerson said.
Strikers tended to be venomous snakes, boa constrictors, and pythons. Lungers, such as kingsnakes and pine snakes, are non-venomous species.
Ryerson was not surprised that different species had different teeth morphologies, but he was surprised that they corresponded so clearly with strike behavior. He will investigate more species of snake to see if this trend continues, or if there are other attack styles.
He also thinks his research could be beneficial to the field of engineering. “If you need an object to pierce or grip something, it needs to be more than just sharp. The shape of the tool could be informed by how the person might use it,” he told Science.org.
