Biomedical Engineering Reference
In-Depth Information
FIGURE 4.1
Old World monkey skulls illustrating
sexual dimorphism (superior-oblique view of
Macaca mulatta, rhesus macaque). (A) adult male;
(B) adult female. Note differences in overall size,
development of supraorbital ridges, breadth of zygo-
matic arches, length of face, and prognathism associ-
ated with differences
in canine
size
and root
development. (Drawings by Nancy Hong.)
FIGURE 4.2
Old World monkey skulls illustrating sexual dimorphism (lateral view of Macaca mulatta). (A) Adult male; (B) adult female. In
addition to the features noted in
Figure 4.1
, also note differences in size of the nuchal line (crest), width of the ascending ramus of the mandible, and length
of the maxilla. (Drawings by Nancy Hong.)
Kessler, 1983
). Also fairly common are neural tube defects,
involving a failure of the vertebral arch components to
fuse properly during development, with or without
accompanying herniation of meningeal and neural tissues
from the vertebral canal. Developmental defects of dental
enamel are also common in nonhuman primates (
Guatelli-
Steinberg and Skinner, 2000; Newell et al., 2006;
Guatelli-Steinberg and Luckacs, 1998
). Anomalous enamel
formation may be indicative of a genetic syndrome or may
provide useful markers of pre- as well as postnatal stress
(
Guatelli-Steinberg and Benderlioglu, 2006
).
With the sequencing of extant higher primate genomes
such as the already completed human, chimpanzee, and
rhesus macaque genomes, knowledge regarding the
molecular basis of morphology is growing exponentially.
Currently much of the work regarding the molecular basis
of phenotypic variation among higher primates comes
from the perspective of evolutionary developmental
biology.
Stages in the Postnatal Life Cycle
The life cycle of nonhuman primates can be divided into
a series of stages, each one characterized by a distinct
morphology and behavior. These stages include: infant,
juvenile, and adult, which is further subdivided into young,
middle (prime), and aged adult. The exact names and
criteria for each stage, however, may vary and reflect
differences in focus since behavioral, sexual, skeletal, and
dental development are not in complete synchrony.
