Shannon came to genealogy through her family and the laboratory. She holds a BS in biology from Indiana University, and that training still shapes how she works on a research problem: build a hypothesis, test it against the evidence, and follow the evidence wherever it leads. She earned both an MSc and a PhD from the University of Strathclyde in Glasgow, where she now tutors students on the postgraduate program. Her doctoral research examined the transformation of American hereditary lineage societies between 1970 and 2020, combining survey data from more than 1,100 participants with three dozen interviews and comparative case studies.
Her research specialties include genetic genealogy and DNA case work, colonial and early American records, Virginia and the mid-Atlantic, African American research, Scottish and British Isles sources, and paleography, with particular comfort in early modern and colonial hands. She also prepares and evaluates applications for lineage societies.
Shannon is the author of Genealogy Basics in 30 Minutes, which appears on the Library of Congress recommended reading list, and is co-author of The DNA Guide for Adoptees. She has also lectured in the US and internationally at both genealogical and academic conferences