Fake eels could show that we are underestimating the brain power of our gilled relatives. Redouan Bshary of the University of Neuchatel explains how his observations of grouper fish hunting together with moray eels plus inventive experiments with fake eels led him to discover fish abilities known previously only in primates. Footage from Bshary, Hans Fricke and Alex Vail shows off the groupers' sea-smarts in the lab and in the wild.
Learn more about Bshary's work in the Nature feature 'Animal behaviour: Clever fish': http://www.nature.com/doifinder/10.1038/521412a
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