"The discovery of America was followed by possibly the greatest demographic disaster in the history of the world." Research by some scholars provides population estimates of the pre-contact Americas to be as high as 112 million in 1492, while others estimate the population to have been as low as eight million. In any case, the native population declined to less than six million by 1650. Revised second edition, 1992, with a new hemispheric estimate of 54 million.