How did Great Dying that ended the Premian era occur?
long environmental problems, not a sudden catastrophe, might have led to the Great Dying that ended the Permian era 250 million years ago, says a new study. The event wiped out 90 per cent of marine creatures and 70 per cent of the land dwellers. Whether these extinctions were caused by meteor impacts, massive volcanic eruptions or long-term pressures is still a contentious issue and the new findings revive the argument that mass extinctions were mostly slow protracted crises.
Two us scientists claim the Permian, and the following Triassic era extinction episodes might have been caused by a steady deterioration of the global environment, fuelled by volcanic eruptions and global warming. Their research, published in the November issue of the journal Geology, could help scientists predict the effects of climate change on today's marine life.
Researchers from the University of Southern California, Los Angeles, reached the conclusion after studying fossils of bryozoans