Stanford Earth Young Investigators: Biodiversity (a.k.a, The History of Life Internship) is an intensive, 8-week research and learning experience for Bay Area high school students. The program combines classroom learning, field trips, and authentic scientific research. The centerpiece of the program is cutting-edge research in the field of paleobiology. Students will conduct original analyses to better understand the evolutionary history of ancient life. An important part of the program is learning how to formulate and test scientific hypotheses. In 2020, major theme for the summer will focus on factors that influenced body size evolution of early major fossil groups (Cambrian and Ordovician)(molluscs, echinoderms, hyoliths, and brachiopods).