Temporal bone
Irregular bone, part of the core skull (axial skeleton)
Also known as: Temple bone, side-head bone
Classification
Irregular bone, part of the core skull (axial skeleton)
Dimensions
A complex, multi-part curved plate roughly the size of an adult fist, forming a major section of the side and lower base of the skull.
Key Features
Look for a smooth, curved plate on the side of the head featuring a prominent arch pointing forward toward the cheekbone, plus a smooth downward-pointing bump behind the ear opening.
Similar Bones
Can be confused with other flat or curved skull bones like the parietal bone or frontal bone. The temporal bone is easily told apart by its complex shape, the bridge-like arch extending forward, and the hollow ear canal opening.
Across Species
In mammals, the temporal bone famously houses the three tiny inner ear bones—the hammer, anvil, and stirrup—which evolved from reptilian jaw bones. Birds and reptiles have a simpler arrangement with fewer fused pieces and lack this exact combination of ear architecture enclosed within a single skull element.
Evolutionary History
The temporal bone is a masterpiece of evolutionary fusion. Over hundreds of millions of years, several distinct ancestral bones that once formed part of the lower jaw and the side of the head in ancient fish-like ancestors merged together to create this single, multi-functional structure in mammals.
Photography Tips
Photograph from the side with the camera level with the middle of the skull. Use soft, angled lighting to highlight the curved surfaces and the bridge-like arch, and include a coin or ruler nearby for scale.