14.3 Lesson 14.3: Primates and Humans
Lesson Objectives
- List and describe general traits of primates.
- Summarize mating systems of primates.
- Review the types of habitats primates can be found in.
- Describe the three main groupings of primates.
- List the traits of the hominids, their diet, reproduction and social system.
Check Your Understanding
- What are general traits of mammals?
- Describe the mating systems in mammals.
Introduction
If primates are mammals, what makes them seem so different? Primates, including hu-
mans, have several unique features only belonging to this group of mammals. Some of these
adaptations are obvious, others not so obvious. Some of these features give primates ad-
vantages such that allow them to live in certain habitats, such as arboreal habitats, such as
trees. Other features have allowed them to adapt to complex and new social and cultural
situations.
What are Primates?
The biological order Primates, mostlyomnivorous(eating both plant and animal material)
mammals, contains all the species commonly related to the lemurs (Figure14.21), monkeys
(Figure14.22) and apes ((Figure14.23), the latter including humans ((Figure14.24). All
primates have five fingers (pentadactyl), a generalized dental pattern, a primitive (nonspe-
cialized) body plan and certain eye orbit characteristics, such as a postorbital bar (a bone,
which runs around the eye socket). While an opposable thumb (the only digit on the hand
able to turn back against the other four fingers, thereby refining the grip in order to hold
objects) are a characteristic feature of this group, other orders, such as opossums, also have
this feature.
In intelligent mammals, such as primates, the cerebrum is larger relative to the rest of
the brain. Indications of intelligence in primates include the ability to learn and complex
behavioral flexibility, involving much social interaction, such as fighting and play.
Old World species (apes and some monkeys as seen inFigure14.25) tend to have signifi-