Overkill Hypothesis

The overkill hypothesis concerns the extinction of megafauna, particularly in the Americas and Australia. Archaeological excavations reveal that a number of species, perhaps more than 100, disappeared within a comparatively short period of time, less than 1,000 years.

Excavations also demonstrate that at least some of those animals were hunted and eaten by newly arriving humans. The hypothesis follows that the migrating humans were responsible for the extinctions because the animals were not frightened of them and so were easily hunted. A contrast is drawn with the megafauna of Africa and Eurasia, where a long period of cohabitation with humans taught the animals to be wary of humans. This hypothesis is controversial because the evidence does not convince all observers, and alternative explanations have been suggested, ...