Orcas, also called killer whales, are actually the largest members of the dolphin family and are among the most intelligent and powerful predators on Earth. They live in every ocean, from the Arctic to Antarctica, and can grow up to about 9.8 meters (32 feet) long and weigh as much as 10,000 kilograms (22,000 pounds). Orcas are easily recognized by their black-and-white coloration and tall dorsal fins, especially in males. They live in highly social family groups called pods, often staying with their mothers and relatives for life, and communicate using unique clicks, whistles, and dialects that vary between populations. Using echolocation, they can navigate and hunt with remarkable precision. Different groups specialize in different prey, including fish, seals, sea lions, penguins, sharks, and even large whales, and they use sophisticated cooperative hunting techniques such as creating waves to wash seals off ice floes. They have no natural predators and are considered apex predators, though they face threats from pollution, habitat degradation, ship strikes, and declining food supplies. Wild orcas are generally not dangerous to humans and are widely admired for their intelligence, complex social lives, and important role in marine ecosystems.