David Haig received his bachelor and doctoral degrees from Macquarie University in Sydney Australia. His doctoral thesis addressed the evolution of plant life cycles, with a particular focus on parent–offspring conflict during seed development.
Consideration of this question lead to a theory to explain the evolution of genomic imprinting in terms of an internal conflict between genes of maternal and paternal origin. He was a Royal Society Endeavour Fellow in the Department of Plant Sciences at Oxford University (1990–1991) and then a Junior Fellow in the Harvard Society of Fellows (1992–1994). Since then he has been a member of the Department of Organismic and Evolutionary Biology at Harvard University. His many obsessions are united by a fascination with the natural history of the genome with interests in intragenomic conflicts, maternal-fetal relations, and the life history of mosses.