 The study suggests that at least 1300 to 1500 bird species, 12% of the total, have gone extinct since the late Pleistocene, with 55% of these extinctions undiscovered. The Pacific accounts for 61% of total bird extinctions. Bird extinction rate varied through time with an intense episode in 1300 CE, which likely represents the largest human-driven vertebrate extinction wave ever, and a rate 80, 60 to 95, times the background extinction rate. Thus, humans have already driven more than one in nine bird species to extinction, with likely severe and potentially irreversible ecological and evolutionary consequences. This article was authored by Rob Cook, Ferran Sayall, Tobias Anderman, and others.