Correction

EVOLUTION. For the article “Independent adaptation to riverine habitats allowed survival of ancient cetacean lineages” by Insa Cassens, Saverio Vicario, Victor G. Waddell, Heather Balchowsky, Daniel Van Belle, Wang Ding, Chen Fan, R. S. Lal Mohan, Paulo C. Simões-Lopes, Ricardo Bastida, Axel Meyer, Michael J. Stanhope, and Michel C. Milinkovitch, which appeared in number 21, October 10, 2000, of Proc. Natl. Acad. Sci. USA (97, 11343–11347), the authors note the following. “We apologize that acknowledgment to Manuel Garcia Hartmann for tissue samples was inadvertently omitted from the published article.”