Todd was born and raised in a small town in northern Ohio. He became interested in Lepidoptera at an early age, thanks to his father, who was a high school chemistry teacher. Summers would involve rearing saturniid moths and traveling the state collecting butterflies, moths, and other insects. Todd joined the Ohio Lepidopterists at around age 10, and was very active in that organization for the next 20 years. He began collecting micro moths in the early 1990's during the height of the Ohio Survey of Lepidoptera, and eventually became interested in moths in the family Tortricidae, which remain his specialty. His undergraduate education began at Ohio Northern University and continued at Ohio State University (OSU) where he earned a bachelor's degree in entomology. His original plans to attend graduate school were postponed when his wife moved from Sydney, Australia to Ohio, and he spent the next eight years in the field of computer systems administration. Deciding that studying moths was better than being employed, he left the computer world and returned to OSU to obtain a M.Sc. in entomology. In 2007 he moved with his wife and two dogs to Colorado to pursue a Ph.D. His dissertation at Colorado State University (CSU) focused primarily on the systematics and identification of economically important tortricids.
Todd currently works as a Taxonomist for the USDA-APHIS-PPQ-S&T Identification Technology Program (ITP) located in Fort Collins, Colorado. He is primarily involved in developing new cutting-edge molecular-based diagnostic assays for the identification of invasive Lepidoptera. Todd has authored or coauthored approximately 30 peer-reviewed publications, including two books, mostly on the systematics of Tortricidae. He maintains a website dedicated to tortricids and has performed extensive field work across North America, Europe, Australia, and Africa. He has received numerous awards for his entomological work, the most notable including CSU's inaugural University Distinguished Professors Scholarship (2012), the Entomological Society of America's John Henry Comstock Award (2011), and the USDA-APHIS-PPQ Deputy Administrator's Safeguarding Award (2011). Todd served as President of the Lepidopterists' Society from 2013-2015 and also holds an affiliate faculty position in the Department of Bioagricultural Sciences and Pest Management at CSU.