The family Phocidae, commonly known as true seals, includes a variety of marine mammals found in oceans around the world. These seals are characterized by their streamlined bodies and lack of external ear flaps, which helps them swim efficiently. They primarily inhabit cold waters, where they hunt for fish, squid, and other marine creatures. True seals are known for their unique adaptations, such as their ability to dive deep and hold their breath for long periods. Some well-known members of this family include the harbor seal and the elephant seal. They play a vital role in marine ecosystems and are often studied for their behaviors and interactions with other species.