The chapter reflects on the impact of two waves of human colonization on North American biodiversity, focusing on three species’ literary archives. The first wave, the Bering land bridge migration during the late Pleistocene epoch, resulted in the extinction of megafauna such as mammoths. European settler-colonization beginning in 1492 resulted in the ongoing decimation of biodiversity, often termed the Sixth Extinction. Indigenous accounts of the mammoth, which may have persisted in oral tradition from the Pleistocene forward, came to the attention of Euro-American naturalists beginning in the eighteenth century. Exemplary authors include Thomas Jefferson and Joseph Nicolar. Ongoing interest in extinct megafauna has inspired proposals for “rewilding” ecosystems. The passenger pigeon was a wonder, a pest, and a source of food to early European colonists. After its extinction, it was mourned a symbol of settler-colonists’ decimation of the natural environment. Authors include John James Audubon, James Fenimore Cooper, and Simon Pokagon. The monarch butterfly, a candidate for Endangered Species designation, is threatened by local habitat destruction and global climate change but has inspired hopeful literary accounts. Authors include Barbara Kingsolver and Donna Haraway. A brief conclusion puts North American extinctions in global perspective.