Ullica Christina Olofsdotter Segerstråle (born October 10, 1945) is a Finnish sociologist and historian of science who is professor of sociology at the Illinois Institute of Technology. Segerstråle’s published nonfiction books include Defenders of the Truth: The Battle for Science in the Sociobiology Debate and Beyond (2000) and Nature’s Oracle: The Life and Work of W. D. Hamilton (2013), the latter of which is the first biography of evolutionary biologist W.D. Hamilton.