Chemical traces preserved in ancient rocks indicate that marine environments were deteriorating long before the catastrophe that wiped out vast numbers...
The 246-million-year-old specimen represents the geologically oldest sea-going reptile from the southern hemisphere.
This image shows nothosaurs swimming...
A mass extinction some 201 million years ago may have been triggered by changes in the biochemical balance of Panthalassa (also known as the Panthalassic...
