Freshwater fish at the top of the food chain evolve more slowly


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For fishermen and anglers, the largemouth bass is a favorite freshwater fish with an appetite for minnows. A new study finds that once they evolved to eat other fish, largemouth bass and fellow fish-feeders remained relatively unchanged compared with their insect- and snail-eating cousins. NESCent postdoc Brian O'Meara and colleagues report that as these fishes became top predators in aquatic ecosystems, natural selection put the brakes on evolution.
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