June 9, 2017
Shark Fact Friday #6: TEETH
BY: Mariah Pfleger
Welcome to Shark Fact Friday, a (mostly) weekly blog post all about unique sharks and what makes them so awesome.
This week is all about the most feared portion of the shark – the teeth.
Sharks as a group exhibit a wide array of tooth morphology, which is just a fancy way of saying that their teeth come in many shapes and sizes. But did you know that different tooth shapes serve different functions?
For comparison, think of your knife set at home. Some of your knives have smooth blades and some are more serrated for getting through really tough things, but both are good for cutting. The same goes for shark teeth!
Some have extremely smooth and pointy teeth like the porbeagle shark:
Some have lots of serrations like the great white:
And some have a combo of both, with the bottom jaw full of teeth specialized for puncturing and the upper jaw with serrated teeth for sawing.
A cool example of teeth made for a specific function is the teeth of the tiger shark, pictured here:
You’ll notice that they are highly serrated and with a bend in them. This is in part because tiger sharks love to snack on sea turtles and these teeth are perfectly designed to saw through their shells. (Sorry sea turtle lovers!) Tiger sharks are known for grabbing their prey, and rather than biting straight down, they shake their heads back and forth so the teeth act more like a saw.
If a shark loses one of its teeth in the process of eating, it’s no bother to them! Sharks shed thousands of teeth and their jaws have new ones arranged in layers that can move into place when one is lost. The picture below is what the back of a shark jaw looks like with the new teeth lined up and ready to go.
BONUS FUN SCIENTIFIC STUDY: In 2016, researchers set out to test how well certain types of shark teeth cut through prey. How did they do that? Well, they glued shark teeth to saw blades and cut through salmon. Don’t believe me? Watch the video! http://rsos.royalsocietypublishing.org/content/3/8/160141.figures-only
OPINION TIME: The coolest teeth belong to the deep sea sixgill shark.