Page 68 - (DK) Danger! Open with Extreme Caution!

Aftermath The Ordovician-Silurian extinction was caused by two scenarios occuring one after the other: first there was a drop in sea levels as glaciers formed, followed by rising sea levels as the glaciers melted. Creatures living near the coasts, such as mollusks and eel-like conodonts, were hit hardest. No one knows exactly what caused the Late Devonian extinction. What we do know is that the temperature dropped massively, twice, perhaps bec

Impact

Percentage of life lost 25% 19% 90% 50% 50%

http://www.THE_END_OF_THE_WORLD.com

The Big Five Date Event 444 million years ago 364 million years ago 250 million years ago Between 214–199 million years ago 65 million years ago

YPSE NOW! Since life began here on Earth, life has ended for one species after another through extinction. Typically, a species will become extinct within 10 million years of its first appearance. More than 98 percent of the species that have ever lived are now extinct! When extinction is sudden and catastrophic, it is called a mass-extinction event. What caused these mass extinctions, and what is There have been mass extinctions throughou

APOCAL the forecast for us? HOME The Big Five

68
(c) 2011 Dorling Kindersley. All Rights Reserved.