The Study of Growth - An Invariant Approach to Statistical Analysis of Shapes - page 231

Facial growth in Macaca fascicularis is characterized by large mag-
nitudes for those distances from ZMS to IDS and to PMM. These linear
distances measure the degree of prognathism in the Macaca fascicu-
laris face, or the degree to which the lower face projects from the orbits.
The distance between NSL and IDS changes substantially during
growth. The linear distances indicate a principal extension of the ante-
rior portion of the maxillary alveolus in relation to the midface asa
result of growth from early postnatal life to adulthood. The distance
between the midface and posterior palate (measured from ZMS to PNS)
experiences the smallest magnitude of change during this time interval.
Facial growth in Macaca fascicularis is of a greater magnitude than
the facial growth occuring in Cebus apella . This is not surprising given
that Macaca fascicularis adults are considerably larger than Cebus
apella adults. Estimates of adult body weight for wild caught Cebus
apella males range from 2646 to 3300 g (Napier and Napier, 1967;
Leutenegger and Cheverud, 1982; Harvey and Martin, et al., 1987)
while Macaca fascicularis adult males achieve an adult body weight of
approximately 4930 g (Fleagle, 1988).
Simply looking at similar entries in the two growth matrices pro-
vides a comparison of growth patterns for these two species. However,
comparison of these two relatively small matrices is tedious and this
task becomes increasingly difficult as the number of landmarks
increases. Moreover, we would like to be able to compare patterns with-
in these matrices, rather than just single elements. A growth difference
matrix that compares growth for these two species, GDM CA-MF , is given
below.

NSL IDS PMM ZMS MXT PNS

NSL 0.00000

IDS 0.72646 0.00000

PMM 0.85382 0.95952 0.00000

ZMS 0.84672 0.69399 0.67075 0.00000

MXT 0.84000 0.77311 0.72624 0.85439 0.00000

PNS 0.89557 0.78804 0.77696 0.99109 0.81469 0.00000

When the elements of this growth difference matrix are arranged in
ascending order, we obtain the following vector: