Metapodial
Long bone, part of the appendicular skeleton
Also known as: Cannon Bone or Foot Bone
Classification
Long bone, part of the appendicular skeleton
Dimensions
Typically ranges from several inches to over a foot in length depending on the mammal species, characterized by a straight, sturdy shaft flanked by broader, blocky ends.
Key Features
Features a strong, roughly rectangular midsection with broad, squared-off ends containing visible spongy interior texture where the ends have been naturally worn or separated.
Similar Bones
Can be confused with the main shaft portions of large limb bones like the upper arm or thigh bone, but is generally straighter and more symmetrical with squared, blocky ends designed for joint surfaces rather than ball-and-socket connections.
Across Species
In running mammals like horses and deer, metapodials are greatly elongated and fused to add extra length and spring to the stride. In bears and humans, they remain separate bones forming the framework of the palm or sole.
Evolutionary History
Over millions of years, hoofed mammals evolved longer and fewer metapodials, transitioning from multi-toed forest dwellers into single-toed or two-toed runners built for speed across open grasslands.
Photography Tips
Photograph with bright, natural side-lighting to highlight the surface texture and contours. Include a coin or ruler for scale, and capture both the wide face and the narrow profile view.