Head

Click on a specific bone from the list below to view the actual scanned rendering of that bone.

Skull

The orca skull, like ours, holds the brain and main organs for seeing, hearing, smelling, and tasting. Orca eyes are on each side of the head, just above the corner of the mouth. The eyes aren't especially large since orcas use sound more than vision while hunting and navigating underwater. Orca ears are just small openings directly behind the eyes. Unlike our ears, they have no exterior flap of skin. Notice the bump on the "forehead" of this photograph of an orca.

That bump is a fatty organ called the melon. The orca can change the shape of its melon to focus and direct the echolocation clicks it uses to hunt food and identify objects underwater. Since the melon has no bones, it doesn't appear in the scanned image of the boney skull.

Lower Jaw

The orca's lower jaw is made up of two large bones called mandibles. Each is filled with special sound-transmitting fat that allows underwater sound to be carried to the ear bones in the skull. HOPE's upper and lower jaws together hold a total of 46 teeth – 22 upper and 24 lower. These cone-shaped teeth interlock like a zipper when the orca closes its mouth. The teeth can pierce the skin of a marine mammal being attacked and also enable the orca to tear off pieces of meat. The tongue then pushes the food into the back of the mouth, where it's simply swallowed. Orcas don't chew their food at all.

Hyoid Bones

The hyoid bones are attachment points for the orca's large muscular tongue. They also support the muscles that move food into the back of the mouth and control swallowing.