Delightful Dolphins
Credit: U.S. Fish and Wildlife Service

Dolphins are warm-blooded marine mammals that breathe air through a blowhole, or nostril, that is located at the top of their heads. The nearly 40 species of dolphins vary in size and appearance, with some characterized by their blunt, rounded heads, while others, such as bottlenose dolphins, having elongated jaws that form a beak. The above bottlenose dolphin was caught on film as it swam after a research boat in Florida's Banana River, near the Kennedy Space Center.