Temporal Bone
Irregular Bone, part of the core skull (axial skeleton)
Also known as: Temple Bone or Ear Bone Area
Classification
Irregular Bone, part of the core skull (axial skeleton)
Dimensions
Compact and irregular, typically measuring around two to three inches across in mid-sized mammals, featuring a complex three-dimensional shape with several distinct fused parts.
Key Features
Characterized by a smooth, arched upper dome, a prominent finger-like projection pointing downward, and a deep hollow socket meant for the jaw joint, alongside a distinct opening leading to the inner ear canal.
Similar Bones
Can be confused with other flat or irregular skull bones like the parietal or occipital bones. It is easily distinguished by its unique hollow socket for the jaw and the tiny, hard ear capsule embedded within its lower portion.
Across Species
In mammals, this bone houses the most delicate and intricate structures of hearing, evolving from bones that once formed part of the lower jaw in ancient reptile-like ancestors. Birds have a simplified structure without an external ear opening, while marine mammals like whales have massively dense versions of this bone to help them hear underwater.
Evolutionary History
Tracing its roots back through the transition from early land-dwelling tetrapods to mammals, the pieces of this complex skull region migrated and transformed over hundreds of millions of years, eventually incorporating the tiny bones of the inner and middle ear.
Photography Tips
Take pictures against a neutral, matte background with bright, even side-lighting to highlight the deep hollows and projecting bumps. Include a ruler or coin for scale, and capture multiple views showing the outer side, the inner side, and the bottom jaw joint.