Growth of the Original Tail in Anolis grahami: Isometry of the Whole Is a Product of Regional Differences

The original tail of lizards is a segmental structure, each segment containing a vertebra. We examine how the growth of the original tail of Anolis grahami is characterized as a single structure and as a structure composed of discrete segments. It is hypothesized that the tail grows isometrically both in its entirety and regionally. The results reveal that the entire tail grows isometrically with reference to SVL but that this isometric growth pattern results from differential growth in successive regions of the tail. Segmentally the tail grows faster proximally than distally and incorporates a middle transitional region. These findings may have implications for the various patterns of tail growth in squamates with different functional roles of the tail.