Against the Tide: Currents Keep Dolphins Apart; Study Finds Invisible Oceanographic Factors That Keep Populations Separate

ScienceDaily (Mar. 24, 2011) — Conservationists from the Wildlife Conservation Society, the American Museum of Natural History, and other conservation and research groups have discovered that groups of dolphins in the western Indian Ocean do not mix freely with one another. In fact, dolphin populations are kept separate by currents and other unseen factors.

http://www.sciencedaily.com/releases/2011/03/110324153708.htm

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