Vertebra
Irregular bone; part of the axial skeleton (the central core)
Also known as: Backbone, spinal segment, or vertebrae (plural)
Classification
Irregular bone; part of the axial skeleton (the central core)
Dimensions
Typically broad and sturdy with various protruding wings; size varies significantly depending on its position in the column, generally getting larger toward the bottom.
Key Features
Look for a solid, drum-shaped cylinder at the front and a large central hole for the spinal cord. It typically has several prominent wings or spikes sticking out to the sides and back, which resemble a butterfly or a stylized airplane when viewed from certain angles.
Similar Bones
To the untrained eye, fragments might be confused with parts of the pelvis or the base of the skull. You can tell it is a vertebra by the distinctive central circular opening and the smooth, flat surfaces on the drum-shaped part where it would stack with its neighbors.
Across Species
Most mammals, from tiny mice to giant giraffes, share a similar basic vertebral structure. Whale vertebrae are massive and lack the locking mechanisms found in land animals, allowing for more flexible swimming. In birds, many vertebrae are fused together to provide a rigid platform for flight muscles. Snakes have hundreds of nearly identical vertebrae to support their undulating movement.
Evolutionary History
The backbone is the hallmark of the vertebrates, evolving from a simple flexible rod called a notochord. Over millions of years, these bony segments developed to protect the central nerve cord and provide a sturdy anchor for ribs and powerful muscles, allowing early ancestors to leave the water and support their weight on land.
Photography Tips
Take photos from multiple angles: one looking straight down through the central hole to show the 'wing' span, and another from the side to show the thickness of the drum-shaped body. Placing a coin or ruler next to it helps show the scale.