The Family Physeteridae consists of large toothed whales, most notably the sperm whale (Physeter macrocephalus). Members of this family are characterized by massive heads containing the spermaceti organ, used for echolocation and buoyancy control. They have conical teeth in the lower jaw, deep-diving abilities, and are primarily carnivorous, feeding on squid and deep-sea fish. Physeterids are highly social, often forming pods, and are found in oceans worldwide. They play a key role as apex predators in marine ecosystems and are notable for their complex behaviors, vocalizations, and long lifespans.