Robert Hall Haynes, OC, FRSC (August 27, 1931 – December 22, 1998) was a Canadian geneticist and biophysicist. He was the Distinguished Research Professor in the Department of Biology at York University. Haynes was best known for his contributions to the study of DNA repair and mutagenesis, and for helping promote the concept of terraforming through his invention of the term, ecopoiesis.