The cuckoo catfish, found only in Lake Tanganyika, tricks cichlids into scooping up its eggs in their mouths and raising the catfish hatchlings, which then eat the cichlid's brood while still inside its mouth

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The cuckoo catfish, found only in Lake Tanganyika, tricks cichlids into scooping up its eggs in their mouths and raising the catfish hatchlings, which then eat the cichlid's brood while still inside its mouth