Male animals are well-known for their sexual ornamentation, from a peacock's flashy colors to a buck's outsized antlers. But scientists are now discovering that females also have decorations to attract a fellow's eye. Take the African cichlid fish, Pelvicachromis taeniatus. Females of this species develop huge, purple pelvic fins, which they fan during courtship. The flirtation works: In laboratory experiments, males clearly preferred females with the largest fins. It's the first case biologists have found where the size of a particular female ornament influences the male's mating decision, the team reports online today in BMC Evolutionary Biology. That may be because only the healthiest females are able to grow the big, flashy fins, the researchers say.
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