In an interesting new study, researchers have revealed that several ancient volcanic eruptions actually helped the dinosaurs to dominate the planet and thrive for so many millions of years. The volcanic eruptions started happening about 230 million years ago which caused significant changes to the environment and ecology such as Earth’s carbon cycle as well as the climate.
Researchers came to this conclusion by studying sediment and fossil plant records that came from a lake in the Jiyuan Basin in the northern part of China. They noticed that there was more humidity and higher temperatures that were caused by extreme volcanism and climatic shifts. These environmental changes included the CPE’s (Late Triassic Carnian Pluvial Episode) “mega monsoon” climate around 234 to 232 million years ago. When these changes occurred, massive amounts of marine creatures were wiped out, conifer trees increased in numbers, and dinosaurs became dominant.
Jason Hilton, who is a professor of paleobotany and paleoenvironments at the University of Birmingham in Britain and a co-author of the study, went into further details, “Within the space of two million years the world's animal and plant life underwent major changes including selective extinctions in the marine realm and diversification of plant and animal groups on land,” adding, “These events coincide with a remarkable interval of intense rainfall known as the Carnian Pluvial Episode.”
As a matter of fact, the researchers separated the shift that lasted two million years into four episodes that were each caused by a volcanic pulse. These events allowed more carbon to be released into our atmosphere which ended up making our planet warmer and caused large amounts of rain to fall.
Dr. Sarah Greene, who is a Senior Lecturer at the School of Geography, Earth and Environmental Sciences at the University of Birmingham as well as being another co-author of the study, weighed in by noting, “Our results show that large volcanic eruptions can occur in multiple, discrete pulses - demonstrating their powerful ability to alter the global carbon cycle, cause climate and hydrological disruption and drive evolutionary processes.”
While these climatic shifts gave rise to the dinosaurs, experts still aren’t clear as to the reasoning behind it as explained by Emma Dunne who is a paleobiologist at the University of Birmingham but was not involved in the study, “This relatively long period of volcanic activity and environmental change would have had considerable consequences for animals on land.” “At this time, the dinosaurs had just begun to diversify, and it's likely that without this event, they would never have reached their ecological dominance we see over the next 150 million years.”
Well, at least the dinosaurs benefited from the numerous volcanic eruptions that took place millions of years ago – until the asteroid wiped them out 66 million years ago.
The study was published in the journal PNAS where it can be read in full.