• A very brief history
• Problems humans present to the
evolutionary approach to behavior
History (very short) .
Evolutionary approach to human
behavior has gone by various names,
focusing on universals or diversity.
• Politics of the evolutionary
approach & the ‘Naturalistic
Fallacy’
Focus on
universals
• Robert Trivers – the 1st
Evolutionary Psychologist
Human
Ethology
• Genetic Determinism
• Facultative Traits
• Evolutionary Psychology – the basic
approach
Problems humans present to an
evolutionary approach to behavior:
• Individual differences
• Learning/experience is everything.
(What have genes got to do with it?)
(50’s & 60’s)
(Human)
Sociobiology
(70’s & 80’s)
Evolutionary
Psychology
Focus on
variation/diversity
(Cultural
Anthropology)
(Human)
Socioecology
(Human)
Behavioral Ecology
Politics of Sociobiology
(or Evolutionary Psychology)
& the ‘Naturalistic Fallacy’ –
Does the evolutionary viewpoint imply
a particular political point of view?
• Culture is everything.
(What have genes got to do with it?)
• Our psychology does not seem to be
organized around inclusive fitness.
• Many common human behaviors are
patently non-adaptive (contraception,
adoption, drug-taking, risk-taking,
war, Mother Theresa, etc).
• Evolutionary theory when applied to
human behavior is considered morally
repugnant (e.g., ‘Social Darwinism’).
Social Darwinism: During the Industrial
Revolution, many fat-cat capitalists
justified their rewards in terms of “survival
of the fittest”: given this ‘law of nature’,
the fact that we are successful, and you are
not implies that we deserve it and you do
not. An example of the “naturalistic fallacy”.
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The “Naturalistic Fallacy”
Arguments which claim to draw ethical
conclusions from the fact that
something is "natural" or "unnatural".
(Hume; Moore)
Natural selection is a natural process
that increases the frequency of
certain genes and eliminates others,
that yields some kinds of organisms
rather than others; but it is not a
process moral or immoral in itself or
in its outcome, in the same way as
gravity is not a morally laden force.
In order to consider some
evolutionary events as morally right
and others wrong, we must introduce
human values.
~ Francisco Ayala
"The benefit of self-deception
is the more fluid deception of
others. The cost is an impaired
ability to deal with reality.“
Robert Trivers
1971. The evolution of
reciprocal altruism.
Quarterly Review of
Biology 46: 35-57.
1972. Parental investment
and sexual selection.
In Campbell, B. (ed.), Sexual Selection
and the descent of man.
1975. Parent-offspring conflict.
American Zoologist 14: 249-264.
1976. (with Hare, H.). Haplodiploidy and
the evolution of the social insects.
Science 191: 249-263.
1982. (with Newton, H.P). The crash of
flight 90: doomed by self-deception?
Science Digest 111: 66-67.
2011. The Folly of Fools: The Logic of Deceit
and Self-Deception in Human Life.
Basic Books.
Time 1977 & Time 1995: Role of genes
inferred from behavior (and theory)
Time 2004: Key issue is a presumed
gene-behavior correlation
(Trivers/Newton 1982: 66)
Robert Trivers
the first evolutionary psychologist
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Problems humans present to an
evolutionary approach to behavior:
Many of these ‘problems’ arise
from assumption that
evolutionary approach implies
that all behavioral differences
are due to genetic differences.
developmental program.
(Any trait difference can be due to a
genetic difference or an environmental
(experiential) difference.
Obligate trait: Phenotypic difference
is correlated with genetic difference.
Term does not imply that environment
(experience) has no effect in
development or expression of the
trait, only that the trait difference
can be traced to a genetic difference.
Facultative trait: Phenotypic diff. is
The Fallacy of
‘Genetic Determinism’
correlated with environmental diff.
Genotype ‘assumes’ and requires
environmental difference to produce
the phenotypic difference.
Polyphenic development in
spadefoot toad tadpole:
A facultative trait
Summary of Experiments:
No
(Any trait has its underlying genetic-
Bluegill Sunfish Alternative
Reproductive Strategies
Potentially a Facultative Trait
Yes
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