Biology Reference
In-Depth Information
our discussion of shape variables in previous chapters. Because it is uniform, meaning
that the same change occurs everywhere, we need only one descriptor for the change of
the whole organism. In contrast, the non-uniform or non-affine deformations (which involve
the metaphorical bending) have regionally differentiated effects.
A deformation can be broken down into uniform and non-uniform components, as in
Figure 5.3
. Most real biological transformations will have both uniform and non-uniform
components. These components are computed separately, so we describe them separately
(first the uniform, then the non-uniform), but it is important to bear in mind that a com-
plete description, and an accurate illustration, requires specifying all the components.
4
3
5
2
1
6
7
14
15
16
8
13
12
11
10
9
(A)
(B)
(C)
FIGURE 5.3
Ontogenetic change in body shape of S. gouldingi, depicting: (A) total deformation and its two
components; (B) uniform component; (C) non-uniform component.
