Greg grew up in London, Ontario, and was encouraged to play with bugs and other critters by his parents. After summers-long family camping trips to see North America he became a naturalist and a nature photographer. He was also inspired by outings with the McIlwraith Field Naturalists (Nature London) and six summers working as a naturalist in Algonquin Provincial Park. He received a BLA in Landscape Architecture and a master of science in mycology (the study of fungi) from the University of Guelph, followed by a doctorate in mycology from the University of Toronto. He is a Professor in the Department of Biology, Western University. He lives in London, ON with his wife Nina and their two growing boys.