Sharks just got scarier: Their teeth could be more durable as ocean warms, study says

Sharks are more formidable and mysterious than we imagined.

Scientists have found evidence the warming ocean might actually make their notoriously deadly teeth more durable.

The study, published Jan. 13, set out to see if increased “ocean acidification and warming” might have a corrosive effect on sharks’ teeth. (The Australian Port Jackson Shark was singled out.)

What researchers discovered is the teeth are surprisingly resistant — a detail that might also explain why humans are continuously finding stray shark’s teeth that are millions of years old.

Shark choppers are apparently indestructible.

“We found that warming resulted in the production of more brittle teeth ... that were more vulnerable to physical damage,” according to a study abstract in Global Change Biology.

“Yet, when combined with ocean acidification, the durability of teeth increased (i.e. less prone to physical damage due to the production of more elastic teeth) so that they did not differ from those raised under ambient conditions.”

Shark teeth are mostly fluorapatite, a mineral that shows “increased fluoride content under ocean acidification,” the researchers learned.

This “suggests that the sharks could ... produce teeth which are more resistant to corrosion,” the report concluded. “This adaptive mineralogical adjustment could allow some shark species to maintain durability and functionality of their teeth.”

The study was conducted by a team of international researchers from universities in China and Australia.

Scientists are worried about the impact of acidification on sharks because the predators play a key role atop a complex food chain, according to a 2019 article in Scientific American. “Ultimately, sharks could be displaced as apex predators, disrupting entire ocean food webs,” the outlet reported.

Increased ocean acidification is blamed on higher concentrations of carbon dioxide in the atmosphere “due to the burning of fossil fuels and land use change,” according to the National Ocean Service.

“When CO2 is absorbed by seawater, a series of chemical reactions occur resulting in the increased concentration of hydrogen ions. This increase causes the seawater to become more acidic and causes carbonate ions to be relatively less abundant,” the service says.

“Carbonate ions are an important building block of structures such as sea shells and coral skeletons.”

This story was originally published January 24, 2022 at 1:32 PM with the headline "Sharks just got scarier: Their teeth could be more durable as ocean warms, study says."