Biology Reference
In-Depth Information
FIGURE 11.4
Projecting the
three-dimensional trajectory onto
a pair of planes, shape versus
size, measured as log centroid
size and shape versus age.
(developmental) age. Whether age or size provides the more relevant information is some-
times addressed empirically, such as by analyzing the dependence of the variable of inter-
est on both size and age, as in the study of woody plant stem structure and function
(
Rosell and Olson, 2007
). When size is a better predictor of the feature of interest, and
when species are at different developmental stages at the same chronological age, size
might be viewed as a better predictor of both structure and function.
Despite the arguments regarding the merits of analyses based on developmental age, or
size, some questions cannot be answered without information about chronological age
because they are not about either intrinsic biological age or the predictability of structure
and/or function from size (or developmental age). Instead, they are specifically about the
