In a new study published in the Proceedings of the National Academy of Sciences, University of Miami researcher Sean Bignami, along with NOAA scientists Ian Enochs, Derek Manzello, and UM professors Su Sponaugle and Robert Cowen, report stunning new insight into the potential effects of acidification on the sensory function of larval cobia. The team was the first to utilize 3-D X-rays (micro-CT scans) similar to what a patient might receive at a hospital, to determine that fish raised in low-pH seawater, simulating future conditions, have larger and more dense otoliths (ear stones) than those from higher-pH seawater. Otoliths are distinct calcium carbonate structures within the inner ear of fishes that are used for hearing and balance. The changes resulted in up to a 58 percent increase in otolith mass, and when tested in a mathematical model of otolith function, showed a potential increase in hearing sensitivity and up to a 50 percent increase in hearing range. These findings indicate the potential for significant impact on a key sensory system in fish, with important implications for larval fish recruitment and fisheries replenishment.