Dr. Knight's early passion for the out-of-doors, wildlife, and the study of natural history led him into the natural sciences. He has formal training in zoology, geology, molecular biology, phylogenetic systematics, and anthropology. Dr. Knight's primary research interest is the study of evolution. Early on, he focused on evolution of lizards and snakes. His contributions to this field include studies of comparative biochemistry of snake venoms, description of a new species of alligator lizard, and molecular systematic studies of moccasins, rattlesnakes, and cobras. One study helped resolve a century-old debate on the origin of front-fanged venom systems in snakes.

Dr. Knight has worked with organismal and molecular evolution at the population level and at higher taxonomic levels. He has also published contributions to molecular phylogenetic theory and methodology. In 1982, Dr. Knight's interests began to shift toward evolutionary anthropology, after reading the popular book, "Lucy". It was not until 1996 that Dr. Knight published his first study in the field of human evolution, an extensive survey of DNA nucleotide sequence variation in autosomal pseudogenes for representatives of global human diversity. That study provided evidence for a recent common ancestor for modern humans.

Dr. Knight held a faculty position at Sul Ross State University, where he taught various biology courses at the undergraduate and graduate levels for four years prior to coming to Stanford. While continuing to publish on reptile evolution, one study at Sul Ross reported on DNA affinities of the peoples of northern Mexico, revealing the relative contributions of Europeans, American Indians, and Africans in Mexico. He joined the Mountain lab as it provided the opportunity to focus on research in evolutionary anthropological genetics.