David L. Kirchman was the Maxwell P. and Mildred H. Harrington Professor of Marine Studies at the University of Delaware until he retired in 2020 and was elected as a fellow of the American Academy of Microbiology, the American Association for the Advancement of Science, and the Association for the Sciences of Limnology and Oceanography. Author of over 175 papers and two books, and editor of the "bible" of microbial oceanography (Microbial Ecology of the Oceans), Kirchman worked on the marine carbon cycle in regions around the world, from the Arctic to Antarctica. His findings were instrumental in showing the importance of bacteria and the rest of the microbial loop in the marine carbon cycle. He received a B.A. from Lawrence University and the Ph.D. from Harvard University.