Severity of ocean acidification following the end-Cretaceous asteroid impact

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Tyrrell, Toby, Merico, Agostino, Armstrong McKay, David Ian
• Format: Text
• Language: English
• Published: National Academy of Sciences 2015
• Subjects: Physical Sciences; Ocean acidification
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4450376/; http://www.ncbi.nlm.nih.gov/pubmed/25964350; https://doi.org/10.1073/pnas.1418604112

Ammonites went extinct at the time of the end-Cretaceous asteroid impact, as did more than 90% of species of calcium carbonate-shelled plankton (coccolithophores and foraminifera). Comparable groups not possessing calcium carbonate shells were less severely affected, raising the possibility that ocean acidification, as a side effect of the collision, might have been responsible for the apparent selectivity of the extinctions. We investigated whether ocean acidification could have caused the disappearance of the calcifying organisms. In a first detailed modelling study we simulated several possible mechanisms from impact to seawater acidification. Our results suggest that acidification was most probably not the cause of the extinctions.