WUHAN, CHINA — Scientists say they have evidence that points to a cataclysmic mass extinction event that helped the dinosaurs to rise to dominance.<br /><br />The theory states that the Carnian Pluvial extinction event was triggered by a massive volcanic eruption that lasted 5 million years. <br /><br />This is called the Wrangellian Eruption, which happened around 234 million years ago in an area that is now western Canada. <br /><br />This 5-million-year-long eruption piled lava up to 6 kilometers high and caused the Earth's atmosphere to become 3 to 10 degrees warmer.<br /><br />Eventually, this global warming heated the oceans — and the ocean water evaporated much faster, causing 2 million years of incessant rain across the planet.<br /><br />Scientists call this 2 million years of rain the Carnian Pluvial Event. They say this over-abundance of rain turned the Earth from a dry shrubland into a wet hothouse filled with rain forests.<br /><br />The extreme humidity and different plants of these rain forests caused serious challenges for the animals that dominated the Ladinian period. <br /><br />For reasons still unknown, this wet world killed off most of the dominant Ladinian-period animals and plants, but led to a sudden abundance of early dinosaur types.<br /><br />Eventually, the eruptions stopped, the rain stopped, and the earth became much drier again. Leaving a world filled with dinosaurs and vegetation that suited them.
