Evolutionary Psychology

Introduction

Evolutionary psychology is the scientific study of human nature based on understanding the psychological adaptations humans evolved to cope with the survival and reproductive challenges faced over the long expanse of our evolutionary history.

Evolutionary psychology is not a specialized area in psychology, but a way of thinking in all areas of the field

What is Evolutionary Psychology?

1. Why is the mind designed the way it is?-what causal processes shaped the mind?

2. How is the human mind designed? -what is the structure of the mind?

3. What are the functions of the mind? -what is the mind designed to do?

4. How does the design of the mind interact with the environment to produce behavior?

Key Questions in Evolutionary Psychology

Evolution: changes over time in a living structure

Monet de Lamarck (1744-1829): ◦ Believed species progressed to a higher form◦ Believed that acquired characteristics are

inherited

The History of Evolutionary Thinking

Why do giraffe’s have long necks?

Lamarckian Notions

Similarities of features across species Fossil record reveals changes within species Similarity in embryonic development across

species Component parts often have obvious

function_______________________________________Life is dynamic and purposive, but why?

Curiosities of Nature

Darwin’s Contributions

1. Variation: the raw material for evolution

2. Inheritance: only inherited traits matter in evolution

3. Selection: some traits are selected because they confer survival benefits

Key Ideas in The Theory of Evolution by Natural Selection

The characteristics of organisms that reproduce more than others are passed to future generations at a greater frequency

Malthus (1798): organisms exist in numbers greater than can survive and reproduce, resulting in a struggle for existence.

The Importance of Differential Reproductive Success

Darwin’s Theory of Sexual Selection

Component 1: Intrasexual Competition

Component 2: Intersexual Selection:Preferential Mate Choice

Some genetic changes are not due to natural or sexual selection

Mutations Founder effects Bottlenecks

Genetic Drift

Evolution is not intentional Evolution is gradual Natural selection explains modification Natural selection explains “design” Natural selection unites species into a tree

of descent Natural selection located humans on the

tree of descent

What the Theory Tells Us…

Darwin did not explain genetic inheritance The “argument from personal incredulity” Creationist objections Resistance to being considered animals

subject to the same laws as other species

Objections to the Theory of Natural Selection

The Modern Synthesis (Mendel and Darwin) Ethology: the adaptive nature of animal behavior

(Lorenz) Inclusive Fitness Theory (Hamilton, Williams)- gene’s

eye thinking Trivers: parental investment, reciprocal altruism, parent

offspring conflict E.O. Wilson: Sociobiology

Important Milestones in the Development of the Theory

What are some challenges to each of the following claims?

1. Human behavior is genetically determined2. If it’s evolutionary, it can’t be changed3. Current mechanisms are optimally

designed

Common Misunderstandings

15 billion years ago: birth of the universe 3.7 billion years ago: first life forms 250 million years ago: first mammals 85 million years ago: first primates 35 million years ago: first apes 4.4 million years ago: bipedalism 2.5 million years ago: first stone tools 200 thousand years ago: Neanderthals 100 thousand years ago: modern humans

“Deep Time”

Freud’s Psychoanalytic Theory Williams James and the Functionalist School Behaviorism The lure of cultural variability Harlow’s attachment studies The Garcia Effect Prepared fears The cognitive revolution

Important Moments in Psychology

We have developed specialized information processing mechanisms to solve problems

The problem of combinatorial explosion

Cognitive Mechanisms