A leading cause of a rising pH value in the world’s oceans is human CO2 emission. As more CO2 is released into the atmosphere and absorbed by the oceans, the water becomes more acidic. This poses problems for many organisms – including sharks, a new study showed. Scientists incubated shark teeth in water with pH levels that reflect the current ocean pH, and in water with a pH value that oceans are predicted to reach by 2300. In the more acidic water of the simulated scenario, shark teeth, including roots and crowns, were significantly more damaged. This shows how global changes reach all the way to the microstructure of sharks’ teeth, the researchers said.