Marc J. Defant is a professor of geology and geochemistry at the University of South Florida whose work spans the physical sciences and evolutionary psychology. In recent years, he has published several peer-reviewed articles in psychology journals examining the patriarchy, social constructionism, the gender pay gap, and the methodological weaknesses underlying much of contemporary feminist scholarship. Before turning his attention to the misuse and misunderstanding of science in society, Defant built a distinguished research career in volcanology – focusing especially on the origin of the continental crust.

A major contribution of his geological research is the discovery and definition of a rock type he named adakite, produced in certain modern volcanic arcs. Adakite provides a rare contemporary analog to the granitic continental crust formed more than 2.5 billion years ago, offering insights into how Earth’s early continents were generated.

Defant has received funding from the National Science Foundation, National Geographic, the American Chemical Society, and the National Academy of Sciences, and has published in leading scientific journals including Nature. His popular-science book Voyage of Discovery: From the Big Bang to the Ice Age complements numerous articles he has written for Skeptic, Free Inquiry, and Popular Science. He has also appeared on the Joe Rogan Experience, the Dinesh D’Souza Podcast, along with several other podcasts.

He has served as Editor of Geology and Associate Editor of the Journal of Geophysical Research and has been an invited speaker at institutions such as MIT, Columbia University, Université de Bretagne (Brest, France), UCLA, the University of Georgia, the University of Tennessee, and the Woods Hole Oceanographic Institution. The Chinese government invited him as a keynote speaker at a symposium on continental crust formation.

As one of the first American scientists permitted to work in the remote and militarily sensitive Kamchatka Peninsula during the late Soviet era, Defant conducted pioneering research through a joint grant between the Soviet Academy of Sciences and the National Science Foundation. His fieldwork has also taken him to Costa Rica, Greece, Indonesia, the Lesser Antilles, Panama, and the Philippines. He has delivered a TEDx talk titled Why We Are Alone in the Galaxy.

In addition to academic research, Defant has consulted internationally on gold and diamond geology for De Beers, Placer Dome, Falconbridge, Anglo American, Aurcana Gold, Diamond Fields, and other mining companies in West Africa and Russia.