Knut Schmidt-Nielsen dies

International Prize for Biology winner was a pioneer in the field of comparative physiology

Kirsten Weir
Mar 7, 2007
Knut Schmidt-Nielsen, who helped create the modern field of comparative animal physiology, died of natural causes January 25 at his home in Durham, North Carolina. He was 91. "He was driven by an intense curiosity about how animals work," said his former graduate student Barbara Block, now a professor of marine sciences at Stanford University. "He was the father of the field of animal physiology."
Schmidt-Nielsen was born in Norway and studied biology under Nobel laureate August Krogh in Copenhagen. He moved to the United States in 1946, and joined Duke University eight years later. In the first part of the 20th century, most physiology research revolved around dogs -- but Schmidt-Nielsen changed all that, Duke University biologist Steven Vogel told The Scientist. Schmidt-Nielsen championed a comparative approach to physiology, Vogel said, which helped to integrate the field with evolutionary biology and ecology. For instance, Schmidt-Nielsen and his students applied their questions to a broad range of species -- camels and sand rats, ostriches and alligators, fish and snails. He'd study any creature that he thought might help him answer the big questions about how animals were constructed, Vogel said. "He wanted to know how kidneys worked, so he looked at the animal that places the most severe demands on the kidneys." Schmidt-Nielsen "was one of the very first people to look at how different animals solve the same problems," agreed Sonke Johnsen, a Duke University biologist who considered Schmidt-Nielsen an "intellectual grandfather." Schmidt-Nielsen was particularly interested in desert animals, and in understanding how various creatures dealt with issues such as heat transfer and water loss. He compared species as different as kangaroo rats and camels to understand "the different ways of making a desert animal," Johnsen told The Scientist. When Duke built a new biology building in the 1960s, Vogel recalled, Schmidt-Nielsen convinced the department to construct a "camel room," a climate-controlled room with an enormous camel-sized door. Yet the only camel ever to grace Duke's campus was one cast in bronze: In 1996, a life-size statue of Schmidt-Nielsen considering an eight-foot camel was erected beside the Biological Sciences Building. Last year the "camel room" was renovated to house a teaching lab.Despite his dromedary legacy, Schmidt-Nielsen was also involved in studies of bird respiration and gas exchange in the swim bladders of deep-sea fish, said Vogel. Later in his career, he became interested in questions of scaling and the biology of size.One of Schmidt-Nielsen's strengths was his ability to connect the underlying mechanisms of an animal's physiology to its behavior and life history, said Michael Fedak, Schmidt-Nielsen's former graduate student and a physiologist at the University of St. Andrews, UK. "He was keen to show the elegance of mechanisms, how they clearly and simply led to the functions they had in the animal," Fedak said.Schmidt-Nielsen was also an accomplished writer, penning five books in addition to some 270 papers. He published a memoir in 1998, and his Animal Physiology textbook, now in its fifth edition, is still widely used, Johnsen and Fedak said.Schmidt-Nielsen, who became a U.S. citizen in 1952, was a member of the U.S., French and Norwegian Academies of Science and the Royal Society of the UK. In 1992 he was awarded the International Prize for Biology. He retired from Duke in 1995 but continued to maintain a presence there as professor emeritus. Besides his scientific reputation, he was known in the department as the brewer of the late-morning tea and the host of excellent New Year's Eve parties, according to Vogel. "He had a great deal of fun doing science," he said, "but it was fun in the sense of working hard at it."Schmidt-Nielsen is survived by his wife Margareta, a son and a daughter.Kirsten Weir mail@the-scientist.comImage: Knut Schmidt-Nielsen, 1998. From Duke University Photography.Links within this article:B. Grant: "The powers that might be," The Scientist, March 1, 2007. Block Krogh Vogel Johnsen Phillips: "Study challenges metabolic scaling law," The Scientist, January 26, 2006. by Knut Schmidt-Nielsen"The Camel's Nose: Memoirs Of A Curious Scientist," Knut Schmidt-Nielsen, Island Press, 1998."Animal Physiology: Adaptation and Environment (Fifth edition)," Knut Schmidt-Nielsen, Cambridge University Press, 1997.