New research is using high-resolution 3D scanning to reveal patterns in the design of snake fangs, showing that these needle-like teeth are shaped to match the snake's preferred prey.
Venomous snakes are notorious for their deadly needle-like fangs. These unusual teeth have a tunnel on the inside that runs down the entire length, just like a medical syringe. The venom is thus truly injected when snakes bite into their victims.
But before this venom can be delivered, these fangs first have to puncture their prey. This requires them to be sharp, but not so pointed that they become fragile and break when the tip hits the surface of their food. This is important because not all foods are the same: while rats and mice have soft skin, lizards have scales, and crabs have hard shells.
To show how the sharpness of fangs has become adapted to suit different diets, researchers from Monash University's School of Biological Sciences used high-tech micro CT scanning to create 3D computer models of fangs across the snake family tree. These novel findings were published this week in the prestigious academic journal Evolution.
"We show that the fangs of venomous snakes are adapted to the outer layer of their preferred prey, where slender fangs with sharp tips are found when snakes target soft-skinned prey, while the fangs are more robust and blunt in snakes that feed on scaly and hard-shelled prey," said PhD candidate Silke Cleuren, who led the study.
When comparing fang shape across the venomous snake families, a novel pattern was found: fangs from distantly related snake species with the same prey type have very similar-looking fangs, more similar than closely related species that have different diets.
"Evolution has found ideal solutions for snake fangs - no matter what type of snake, anywhere across the world, the fangs match their favourite food," said Associate Professor Alistair Evans. "This is convergent evolution at its best, solving the problem of how to break into your prey without breaking your fangs," continued Dr Evans.
As well as disclosing the secrets of snakes evolution, practical implications can flow from this work. "Knowing the fang shape that matches a certain diet can help conserve endangered snakes. The fangs tell us the likely preferred diet, so we should find suitable habitat that contains that snake's favourite meal," said Silke Cleuren.
"From knowing how sharp and blunt snake fangs really are, we can design and test protective clothing against snake bites," continued Cleuren. "Now you will know whether you are safe from snake bites when wearing your favourite pair of jeans."
Image: Silke Cleuren with 3D Printed Snake Fang. Image Credit: Silke Cleuren.
