By Susan Milius
Coral reef fish do consumer research in a way that keeps a service-providing species honest, says a new study.
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When parasites build up on the skin of a reef fish, it can get relief by swimming over to a small, so-called cleaner fish that nibbles off the encrustations. Now, lab tests show that potential clients choose cleaners that they’ve seen working attentively, says Redouan Bshary of the University of Neuchâtel in Switzerland.