Born and raised in Ireland, Donal Manahan became interested in marine biology and the study of larvae as an undergraduate working on oyster culture in Ireland. As a graduate student at the Univeristy of Wales in the UK, he studied larvae metabolism, specifically questions such as how much energy larvae need to grow and how they get that energy from the ocean. He came to America in 1980 as a postdoctoral researcher at the University of California, Irvine. He has expanded his interests to study how animal life develops in extreme environments, such as Antarctica. That naturally drew him to investigate the early stages of animals that survive being cold and hungry at another similarly extreme environment, hydrothermal vents. Although the vents themselves are ver hote, the seawater just a few feet away is cold, and like polar regions, has no obvious source of food.