Sharks are more impressive and mysterious than we imagined.
Scientists have found evidence that warming the ocean might actually make their notoriously deadly teeth more durable.
The study, published on January 13th investigated whether increasing “ocean acidification and warming” could have a corrosive effect on shark teeth. (The Australian Port Jackson Shark was singled out.)
What the researchers discovered is that the teeth are surprisingly resilient — a detail that may also explain why people keep finding teeth from stray sharks millions of years old.
Shark choppers are seemingly indestructible.
“We found that warming led to the production of more brittle teeth…which were more susceptible to physical damage,” says a summary of the study in Global Change Biology.
“However, in combination with ocean acidification, the durability of the teeth (i.e. less susceptible to physical damage due to the production of more resilient teeth) increased, so they were no different from those grown under ambient conditions.”
Shark teeth are composed primarily of fluorapatite, a mineral that “exhibits increased fluoride levels with ocean acidification,” the researchers learned.
This “suggests that the sharks…may produce teeth that are more resistant to corrosion,” the report concluded. “This adaptive mineralogical adaptation could allow some shark species to maintain the durability and functionality of their teeth.”
The study was conducted by a team of international researchers from universities in China and Australia.
Scientists are concerned about the impact of acidification on sharks because the predators play a key role at the top of a complex food chain, a 2019 article in Scientific American. “Ultimately, sharks could be displaced as apex predators and disrupt entire ocean food webs,” the outlet reported.
Elevated Ocean acidification is to blame to higher concentrations of carbon dioxide in the atmosphere “due to 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 take place that result in an increased concentration of hydrogen ions. This increase is causing seawater to become more acidic and carbonate ions to be relatively less common,” the service says.
“Carbon ions are an important building block of structures such as mussels and coral skeletons.”
This story was originally published Jan 24, 2022 4:32 p.m.