Biology Reference
In-Depth Information
FIGURE 12.8
Map of
the sites used in the case
study example with
temporal information. EC is
the Extended Coalescent
and PCC is the Postcontact
Coalescent. All site dates are
approximate. North is to the
top of the figure.
particularly suited for the analysis of crania. Post GPA, MorphoJ provides for further analysis
of the fitted coordinates. One method projects the configurations into the tangent plane that
has Euclidean properties allowing for standard statistical analysis of the coordinates. The
other conducts principal components analysis (PCA) of the fitted coordinates and the PC
scores can then be used in traditional statistical procedures. In this case, the projected coor-
dinates are selected and a canonical variates analysis (CVA) is conducted to maximally sepa-
rate the sites and generate plots that can be interpreted as biodistance maps.
Additionally, configurations depicting the morphological pattern associated with group
averages are generated, facilitating interpretations of shape variation. The ability to graphi-
cally depict morphological patterns is one of the great benefits of geometric morphometrics,
which is not possible using traditional morphometrics.
Figure 12.9
is a plot of the mean
canonical scores for each component along the first two canonical variates axes (CV1 and
CV2) along with configurations illustrating the average morphological pattern associated
with each group. The configurations have been scaled by a factor of 5 to facilitate visualiza-
tion of shape difference.
Table 12.2
provides the pairwise Mahalanobis distances among site
components with those that are significant based on 10,000 permutations indicated; both the
Mahalanobis distances and the significance testing were conducted in MorphoJ.
The canonical variate plot (
Figure 12.9
) depicts a clear separation along CV1 between the
cluster of early northern site components (Rygh and Mobridge Feature 1) and all the other
sites. The similar shape of the average face from Rygh and Mobridge Feature 1 is evident
