This document outlines the major scientific movements and developments that led to the field of evolutionary psychology. It discusses early evolutionary thinkers before Darwin like Lamarck and Cuvier. It then covers Darwin's theory of natural selection and sexual selection. Later developments discussed include Mendel's work on genetics, the modern evolutionary synthesis, ethology, inclusive fitness theory, sociobiology, and milestones in human evolution and psychology.

1. The Scientific
Movements
Leading to
Evolutionary
Psychology
Evolutionary Psychology

2. Landmarks in the History of
Evolutionary Thinking
Evolution before Darwin
Lamarck – species progress
toward higher forms/inheritance
of acquired characteristics
Cuvier – catastrophism, species
removed by events like
meteorites, then new species
emergeAlso, evidence from homologies,
strata of fossil record,
ontological similarities
What was the mechanism for
biological structures? How did
changes come about?

3. Landmarks in the History of
Evolutionary Thinking
Darwin’s theory of natural selection
Variation, selection, inheritance
Influence on Darwin
Malthus – organisms exist in numbers far greater
than can survive and reproduce (an essay on the
principle of population)
Differential reproductive success

4. Landmarks in the History of
Evolutionary Thinking
Darwin’s theory of sexual selection
Intrasexual competition
Sexual dimorphism, particularly size
Intersexual selection
Are natural and sexual selection different
processes?

5. Landmarks in the History of
Evolutionary Thinking
The role of natural and sexual selection
in evolutionary theory
Genetic drift: random changes in the
genetic makeup of a population
Mutations, founder effect, and genetic
bottlenecks are all part of genetic drift
Founder effect: a small group breaks
off from larger population: their
characteristic are not representative of
populationGenetic bottleneck: event causes
demise of large portion of population;
those that survive have genes that
don’t represent population

6. Landmarks in the History of
Evolutionary Thinking
The role of natural and sexual selection in
evolutionary theory (cont.)
Evolution is gradual (Lyell)
Darwin believed in blending of characteristics in
sexual reproduction (Mendel)
Objection of religious individuals (immutable life
forms)

7. Landmarks in the History of
Evolutionary Thinking
The modern synthesis: Genes
and particulate inheritance
Darwin didn’t understand
mechanism of inheritance
Mendel’s work clears that up
(genes; particulate, not
blended)Mendel sent papers to
Darwin, but for reasons
unknown he did not absorb
their significanceThe modern synthesis is a
combination of Darwin’s
theory of natural selection
and Mendel’s work on
genetics

8. Landmarks in the History of
Evolutionary Thinking
The ethology movement
Natural selection of behavior
Darwin conceived on natural
selection’s effect on behavior
All behavior requires underlying
physical structures – bipedal
locomotionThrough artificial selection behavioral
characteristics can be changed
Ethology is concerned with species-
specific behaviors – those that are
genetically determined, like imprinting

9. Landmarks in the History of
Evolutionary Thinking
The ethology movement (cont.)
Tinbergen’s four “why’s”?
1. Immediate influence on behavior
2. Developmental influences on behavior
3. Function of behavior
4. Evolutionary or phylogenetic origins of behavior

10. Landmarks in the History of
Evolutionary Thinking
The inclusive fitness revolution
Hamilton – broadens the scope of natural
selection by including other relatives and the
importance of helping their genes get to the next
generationInclusive fitness is the sum of an individual’s own
reproductive success (classical fitness) plus the
effects the individual’s action have on the
reproductive success of his/her genetic relatives

11. Landmarks in the History of
Evolutionary Thinking
Clarifying adaptation and
natural selection
Trivers’ seminal theories
Reciprocal altruism
Parental investment theory
Sexual selection
Theory of parent-offspring
conflict

12. Landmarks in the History of
Evolutionary Thinking
The sociobiology controversy
E.O. Wilson
Sociobiology: The New Synthesis (1975)
Cellular biology, integrative neurophysiology,
ethology, comparative psychology,
population biology, behavioral ecology
Ants to humans – theory could be applied to
all life forms
Synthesized into from:
Inclusive fitness
Parental investment theory
Parent-offspring conflict theory
Reciprocal altruism

13. Landmarks in the History of
Evolutionary Thinking
E.O. Wilson (cont.)
Gave a name to emerging field
Chapter on humans controversial
Sociobiology would ‘cannibalize’
psychology
Claimed sociobiology would explain:
Culture
Religion
Ethics
Aesthetics
Theory lacked support from studies of
humans

14. Landmarks in the History of
Evolutionary Thinking
Common misunderstandings about evolutionary theory
Misunderstanding 1: human behavior is genetically
determinedMisunderstanding 2: if it’s evolutionary, we can’t change it
Misunderstanding 3: current mechanisms are optimally
designed
Milestones in the origins of modern humans

15. Landmarks in the History of
Evolutionary Thinking
Landmarks in the field of psychology
Freud’s psychoanalytic theory
William James and the psychology of
instinctsThe rise of behaviorism
The astonishing discoveries of cultural
variabilityThe Garcia effect, prepared fears, and the
decline of radical behaviorism
Harlowe
Flavor aversion
Prepared fears – taste paired with different
stimuli yield different results
Peering into the black box: the cognitive
revolution