Shark teeth are being eroded

Sharks' teeth – their sharp hunting weapons – are being eroded by rising acidity in seawater.

Shark teeth are designed to cut flesh, not resist acid, and they are becoming more brittle than ever, according to researcher Maximilian Baum from Heinrich Heine University. “They are sophisticated weapons designed to cut flesh, not resist ocean acid,” he said .

Teeth - sharp hunting weapons of sharks. (Source: Getty Images)

As the oceans absorb more and more carbon dioxide due to climate change, they are becoming increasingly acidic.

As the ocean absorbs more and more CO₂, the pH of seawater drops. Currently, seawater has a pH of around 8.1, but could drop to 7.3 by 2300 if this trend continues. This causes shark teeth to crack, puncture, and corrode at the base.

The team collected hundreds of blacktip shark teeth from aquariums and soaked them in water of varying pH levels for eight weeks. The results showed that teeth in acidic environments were significantly damaged: their surfaces were roughened, their structures weakened, and they were more likely to break.

Microscopic image of a tooth kept at pH 7.3 for eight weeks. (Source: Steffen Köhler)

When they were examined at the end of the experiment, the teeth in the acidic water were significantly more damaged than those in the water with a pH of 8.1.

“We observed obvious surface damage such as cracks and holes, increased root corrosion and structural degradation,” said Professor Sebastian Fraune from Harvard University, who oversaw the project.

Acidic water also causes the tooth surface to become rough and uneven. While this may enhance the shark's cutting ability, it also damages the tooth structure, making it weaker and more prone to fracture.

“Maintaining ocean pH near the current average of 8.1 may be critical for the physical integrity of predatory tools ,” Baum said. “This is a reminder that the impacts of climate change ripple throughout the entire food web and ecosystem.”

Although sharks are capable of continuously replacing their teeth, the current rate of erosion may be outpacing their natural ability to repair them. This not only affects the sharks, but also has a ripple effect throughout the marine food chain.

Minh Hoan

Source: https://vtcnews.vn/rang-ca-map-dang-bi-an-mon-ar962394.html