Scientists show how fish save energy by swimming in schools

Researchers at Harvard University and the Massachusetts Institute of Technology have provided new insights into the hydrodynamic benefits fish reap by swimming in schools. "The annual upstream voyage of fish to spawn has long been viewed as one of the classic struggles of the natural world, but our work suggests that this journey may not be nearly as exhausting and heroic as it appears," says author James C. Liao, a graduate student in Harvard's Department of Organismic and Evolutionary Biology. "Rather than swimming blindly upstream through turbulence, swimming fish use specific body motions to yield to natural eddy formations, using energy in the environment to direct their bodies upstream without much muscular investment." The results are reported in the Nov. 28, 2003 issue of the journal Science. Liao was joined in this research by George V. Lauder, professor of biology and Alexander Agassiz Professor of Zoology in the Museum of Comparative Zoology at Harvard, and by David N. Beal and Michael S. Triantafyllou at M.I.T. The work was supported by grants from Sigma Xi, the American Museum of Natural History, the Robert A. Chapman Memorial Scholarship at Harvard, and the National Science Foundation, as well as an M.I.T. Sea Grant.