Widely recognized species (Tursiops truncatus) of mammal belonging to the dolphin family, found worldwide in warm and temperate seas. Bottlenose dolphins reach an average length of 8–10 ft (2.5–3 m) and weight of 300–650 lb (135–300 kg). Males are generally larger than females. A familiar performer at marine shows, the species is characterized by a built-in smile formed by the curvature of its mouth. It has also become the subject of scientific studies because of its intelligence and its ability to communicate with its kind through sounds and ultrasonic pulses.