Chapter 7 & 8

Primate Behavior & Models for Human Evolution

The Evolution of Behavior Behavior

An action in response to internal or external stimuli. Response to environment.

Deliberate or unconscious. Behavioral Ecology

Natural environment

Behaviors Biological traits

Genes

The Evolution of Behavior Behavioral phenotypes transmitted

genetically at faster rate than others. Genetic + Environmental Factors =

Behavior There are different limits & potentials for

learning in various species. (i.e. Rabbit vs. Chimpanzee)

Primate Social Structure Social structures result

from natural selection. Primates are among the

most social of animals.

Factors Influencing Social Structure: Body Size BMR & diet Distribution of Resources Predation Relation to other species Dispersal Life histories Sleeping sites Activity patterns Human activities

Primate Social Behavior: Dominance

dominance hierarchies. Access to resources. Factors influencing dominance status:

Sex • Intelligence Age • Motivation Aggression • Mother’s social position Time in the group

Primate Social Behavior:

Communication Autonomic vs. Deliberate communication.

Reassurance is communicated through hugging or holding hands.

The fear grin, seen in all primates, indicates fear and submission.

Displays communicate emotional states.

Primate Social Behavior: Aggression & Affiliative Behaviors

Competition for resources Signals & displays Tense situations Core area & territorialism Affiliative behaviors

Physical contact Altruism

Patterns of Reproduction Estrus Cycle No permanent bonding Reproductive strategies

K-selected & R-selected Male competition for mates

= sexual selection

Sexual Selection A type of natural selection that operates

on one sex, usually males. Increase frequency of traits (successful

mates). Sexual selection dimorphism Infanticide as a reproductive strategy?

Reasons

Primate Cultural Behavior Basic social unit Polygamous relations, males

are not active. Experiments with orphan

Monkeys. Do apes have culture?

Learned through observation

Examples of culture

Language

Communicating abstract thoughts. Closed system of communication Challenges to these views:

Vervet monkeys Distinct calls for specific references Film examples

The Primate Continuum Humans have bigger brains but same

neurological processes. Ethical dilemmas in the study of our closest

relatives. Should we study/exploit them for our benefit? We cage nonhuman primates without regard

for their needs. Nonhuman primates should be maintained in

social groups and introduced to habitat enrichment programs.

Quick Quiz

1. Dominance hierarchies

a) guarantee that dominant males are more reproductively successful.

b) result in dominant individuals having priority access to food.

c) don't guarantee a reproductive advantage in dominant males.

d) are permanent.

Answer: b Dominance hierarchies result in

dominant individuals having priority access to food.

2. Affiliative behaviors

a) arise when there is competition for resources.

b) enhance group cohesiveness.

c) are rare among primates.

d) may include displays.

Answer: b• Affiliative behaviors enhance group

cohesiveness.

3. Vervet monkey communicationa) is used to support the theory that

primate vocalizations do not include external events or objects.

b) is limited to scent marking and an occasional bark.

c) includes specific sounds for different categories of predators (air, tree or ground).

d) is sophisticated with regard to food.

Answer: c Vervet monkey communication includes

specific sounds for different categories of predators (air, tree or ground).

4. In a group's territory there is usually a _________________ area where the highest concentration of resources can be found.

Answer: core In a group's territory there is usually a

core area where the highest concentration of resources can be found.

In Class Primate ActivityUsing information from chapters 6 & 7 in thetext and the films, form small groups todiscuss the following questions:1. What are some similarities humans share with primates?

(anatomical & behavioral) List 5+2. Define and give an example (3)of the following primate

behaviors:1. Altruism, aggression, communication, dominance &

reproductive strategies.3. List the following:

1. Three examples of Prosimians and Anthropoids as well as their characteristics

2. Discuss why infanticide is seen as reproductive strategy. Do you agree? Why or why not?

3. Describe and give examples of language & cognitive abilities of apes. Do apes have language or only humans do?