It is the largest surviving toothed whale, known for its huge head and unique teeth. There are significant differences in the number and size of teeth between genders and individuals, with males typically having more teeth than females. Having larger teeth that can grow up to 20 centimeters long, conical in shape, mainly located in the lower jaw. Teeth may serve a display function during mating and competition for mates, but are not used for predation. The teeth of female sperm whales are usually smaller and sometimes even underdeveloped, with almost no gum exposed. Sperm whale teeth are composed of dentin, a hard tissue that can resist the immense pressure of deep-sea predation.

It is the largest surviving toothed whale, known for its massive head and complex sonar system. The head accounts for one-third of its body length and contains special ear structures that are crucial for their navigation and communication in deep-sea environments. The ears of sperm whales do not have obvious external ear structures like terrestrial mammals, but are hidden in complex structures on the head. Characterized by high adaptability to deep-sea environments, including an inner ear structure capable of withstanding extreme water pressure. The hearing is very sensitive and can detect very low frequency sounds that travel far underwater, helping to locate prey, navigate, and communicate with companions.