Mass-Extinction Sleuth (image) Brown University Caption Brown University paleobiologist Jessica Whiteside led a scientific team that has explained what led to the dinosaurs' rise as the Triassic Period ended. Fossil and carbon evidence show that volcanic eruptions and a spike in atmospheric carbon dioxide wiped out half of plant species and early dinosaurs' primary competitors. Credit Paul Olsen/Columbia University Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.