Extinction is the cessation of existence of a species or group of taxa, reducing biodiversity. Prior to the dispersion of humans across the earth, extinction generally occurred at a continuous low rate, mass extinctions being relatively rare events. Starting approximately 100,000 years ago, and coinciding with an increase in the numbers and range of humans, species extinctions have increased to a rate unprecedented since the Cretaceous-Tertiary extinction event.
Going the Way of the Polar Bear
by Devin Lavelle
01.04.07 | There is only one bear that will actively track and hunt humans. The polar bear tends to prefer fattier animals, though and the Americans who live in or travel to the Arctic tend to be the heartier sort, so they generally only go after humans when they are suffering from extreme hunger.