Stingrays are cartilaginous fish related to sharks, found in oceans and some freshwater environments worldwide. They have flat bodies with wing-like pectoral fins that propel them gracefully through water. Most species are bottom-dwellers, feeding on mollusks, crustaceans, and small fish. The distinctive venomous spine on their tail is used purely for defense when threatened. Stingrays are generally docile and avoid confrontation with humans. Many species give birth to live young rather than laying eggs. They play an important role in marine ecosystems by controlling populations of bottom-dwelling prey species.