My dissertation focuses on the peculiar relationship the field of New Testament textual criticism has formed with the biological sciences, starting from the eighteenth century and continuing to the present. Strictly defined, modern textual criticism is the study of manuscripts and their readings in order to establish the "original text." How textual criticism came to be defined as such is tied to developments in natural classification and evolutionary biology, from which textual critics borrowed metaphors and structures to describe and relate different manuscripts. It has yet to be asked how the use of biological discourse has shaped textual criticism, its assumptions and possibilities for expansion. These are the issues I will address with a critical history of New Testament textual criticism and proposals for new theoretical approaches.