"The average age of a species before the coming of humanity was very roughly 1 million years. We've speeded up extinction and thus shortened that span by roughly 1,000 times. The amount of information that is lost is approximately equal in pure bits to all of the editions of the Encyclopedia Britannica published since the eighteenth century."
Source: Wilson, Dr. Edward O. "The Future of Life." Presented at the National Conference on Science, Policy, and the Environment, Washington, D.C., December 6-7, 2001. (Verified 04/18/14).