Download Behavior Genetics and Evolutionary Psychology

___________________________________ ___________________________________ ___________________________________ PSYCHOLOGY
___________________________________ (8th Edition, in Modules)
David Myers
___________________________________ PowerPoint Slides
Aneeq Ahmad
Henderson State University
___________________________________ ___________________________________ Worth Publishers, © 2007
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___________________________________ ___________________________________ ___________________________________ ___________________________________ Behavior Genetics and Evolutionary Psychology
___________________________________ ___________________________________ Module 6
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___________________________________ Behavior Genetics and Evolutionary Psychology
___________________________________ Behavior genetics: Predicting Individual Differences
___________________________________ ___________________________________ ƒ Genes: our Codes for Life
ƒ Twin Studies
___________________________________ ƒ Temperament Studies
___________________________________ ƒ Heritability
___________________________________ ƒ Gene‐Environment Interaction
ƒ The New Frontier: Molecular Genetics
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Psychology 8 ed., David Myers Module 6 PowerPoint Slides, Aneeq Ahmad 1
___________________________________ Behavior Genetics and Evolutionary Psychology
___________________________________ Evolutionary Psychology: Understanding Human Nature
___________________________________ ___________________________________ ƒ Natural Selection
___________________________________ ƒ An Evolutionary Explanation of Human Sexuality
___________________________________ ƒ Critiquing the Evolutionary Perspective
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OBJECTIVE 6‐1| Give examples of differences Nature, Nurture and Human Diversity
and similarities within the human family. ___________________________________ Similarities
Differences
___________________________________ Genes: Same set of chromosomes
Genes: Genetic anomalies may make us different
___________________________________ Biology: The organs and body function the same
Biology: May change during development
___________________________________ Brain: Same brain architecture
Brain: Asymmetry of brain across genders
Behaviors: Speak language
Behavior: Speak different languages
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OBJECTIVE 6‐2| Describe the type of Behavior Genetics: Predicting Individual Differences
questions that interest behavior geneticists. ___________________________________ Behavior Geneticists study our differences and weigh the relative effects of heredity and environment.
___________________________________ ___________________________________ ___________________________________ ___________________________________ 6
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OBJECTIVE 6‐3| Define chromosome, DNA, Genes: Our Codes for Life
gene, and genome, and describe their relationships. In the nucleus of a cell chromosomes containing DNA (deoxyribonucleic acid) are situated.
___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 7
___________________________________ Genes: Our Codes for Life
___________________________________ Segments within DNA constitute genes making proteins to determine our development. ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 8
___________________________________ Genome
___________________________________ Genome is the set of complete instructions for making an organism Containing all the genes in that organism. Thus human genome makes us human and the genome for drosophila makes it a common house fly.
___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 9
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OBJECTIVE 6‐4| Explain how identical and Twin Biology
fraternal twins differ, and ways that behavior geneticists use twin studies to understand the To study the effects of heredity and environment two sets of twins, identical and fraternal, have come in handy.
effects of environment. ___________________________________ ___________________________________ ___________________________________ ___________________________________ 10
___________________________________ ___________________________________ Twin and Procedures
___________________________________ Behavior geneticists study the effects of shared and unique environments on total or partial genetic makeup.
___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 11
___________________________________ Separated Twins
___________________________________ A number of studies have looked at identical twins raised separately from birth or close there after and have found a number of similarities.
Separated Twins
___________________________________ ___________________________________ Personality, Intelligence
___________________________________ Abilities, Attitudes
___________________________________ Interests, Fears
Brain Waves, Heart Rate
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___________________________________ Separated Twins
___________________________________ Critics of separated twin studies note that such similarities can be found between strangers. However, researchers point out that differences between fraternal twins are greater than identical twins.
___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Bob Sacha
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OBJECTIVE 6‐5| Cite ways that behavior Adoption Studies
geneticists use adoption studies to understand the effects of environment and heredity. Opposed to twin studies, adoption studies suggest that adoptees (who may be biologically unrelated) tend to be different from their adoptive parents and siblings.
___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 14
___________________________________ Adoptive Studies
___________________________________ Adoptive studies strongly point to the simple fact that biologically related children turn out to be different in a family. So investigators ask:
___________________________________ Do siblings have differing experiences?
___________________________________ Do siblings, despite sharing half of their genes, have
different combinations of the other half genes?
___________________________________ ___________________________________ ___________________________________ Ultimate question: Does parenting have an effect?
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Psychology 8 ed., David Myers Module 6 PowerPoint Slides, Aneeq Ahmad 5
___________________________________ Parenting
___________________________________ Parenting does have an effect on biologically related and unrelated children.
___________________________________ ___________________________________ Parenting Influences children’s
___________________________________ Attitudes, Values
___________________________________ Manners, Beliefs
___________________________________ Faith, Politics
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OBJECTIVE 6‐6| Discuss how the relative Temperament Studies
stability of our temperament illustrates the Temperament refers to a person’s stable emotional reactivity and intensity. Identical twins express similar temperaments, suggesting heredity predisposes temperament.
influence of heredity on development. ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 17
OBJECTIVE 6‐7| Explain heritabilityʹs Heritability
application on individuals and groups, and explain what we mean when we say genes are Heritability refers to the extent to which the differences among people are attributable to genes.
self‐regulating. ___________________________________ ___________________________________ ___________________________________ ___________________________________ 18
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___________________________________ Group Differences
___________________________________ If genetic influences help explain individual diversity in traits, can the same be said about group differences?
___________________________________ ___________________________________ ___________________________________ Not necessarily. Individual differences in weight and height are heritable and yet nutritional influences have made westerners heavier and taller than their ancestors a century ago.
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___________________________________ Nature and Nurture
___________________________________ Some human traits are fixed, like having two eyes, most psychological traits are liable to change with environmental experience.
___________________________________ ___________________________________ ___________________________________ So genes provide choices to the organism to change its form or traits when environmental variables change. Therefore genes are pliable or self‐regulating. ___________________________________ ___________________________________ 20
OBJECTIVE 6‐8| Give and example of a Gene‐Environment Interaction
genetically influenced trait that can evoke responses in others, and give another example Genes can influence traits which affect responses, and environment can affect gene activity.
of an environment that can trigger gene activity. ___________________________________ A genetic predisposition that makes a child restless and hyperactive, evokes angry responses from his parents. A stressful environment can trigger genes to manufacture neurotransmitters leading to depression.
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___________________________________ Gene‐Environment Interaction
___________________________________ Genes and environment affect our traits individually, but more important is their interactive effects.
___________________________________ ___________________________________ Alessia Pierdomenico/Reuters/Corbis
Rex Features
People respond differently to
Rowan Atkinson (Mr. Bean) than Orlando Bloom.
___________________________________ ___________________________________ ___________________________________ 22
OBJECTIVE 6‐9| Identify the potential The New Frontier: Molecular Genetics
promise and perils of molecular genetics. ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Molecular genetics is a branch extension of behavior genetics that asks the question, do genes influence behavior?
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___________________________________ Molecular Genetics: Promises and Perils
___________________________________ Molecular geneticists are trying to identify genes that put people at risk for disorders. With this kind of knowledge parents can decide to abort pregnancies where fetuses are suspected of having such disorders
___________________________________ ___________________________________ ___________________________________ ___________________________________ But this opens up a real concern about ethical issues involving such choices.
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OBJECTIVE 6‐10| Describe the areas of Evolutionary Psychology: Understanding Human Nature
psychology that interests evolutionary psychologists. Molecular genetics studies why we as organisms are distinct.
___________________________________ ___________________________________ ___________________________________ Evolutionary psychology studies why we as humans are alike. In particular it studies the evolution of behavior and mind using principles of natural selection.
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OBJECTIVE 6‐11| State the principle of natural Natural Selection
selection, and point out some possible effects of natural selection in the development of Natural selection is an evolutionary process through which adaptive traits are passed on to ongoing generations because they lead animals to reproduce and survive.
human characteristics. ___________________________________ ___________________________________ ___________________________________ ___________________________________ 26
___________________________________ Artificial Selection
___________________________________ Biologists like Belyaev and Trut (1999) were able to artificially rear and domesticate wild foxes selecting them for friendly traits. ___________________________________ ___________________________________ L.N. Trur, American Scientist (1999) 87: 160‐169
Any trait that is favored naturally or artificially
spreads to future generations.
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___________________________________ Human Traits
___________________________________ A number of human traits have been identified as a result of pressures afforded by natural selection.
___________________________________ ___________________________________ Why do infants fear strangers when they become
mobile?
___________________________________ Why are most parents so passionately devoted to their
children?
___________________________________ ___________________________________ Why do people fear spiders and snakes and not
electricity and guns?
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OBJECTIVE 6‐12| Identify gender differences Human Sexuality
in sexuality. ___________________________________ Gender Differences in Sexuality
Males and females to a large extent behave and think similarly. Differences in sexes arise with regards to reproductive behaviors.
Question (summarized)
Male
Female
Casual sex
60%
35%
Sex for affection
25%
48%
Think about sex everyday
54%
19%
___________________________________ ___________________________________ ___________________________________ ___________________________________ 29
OBJECTIVE 6‐13| Describe evolutionary Mating Preferences
explanations for gender differences in Natural selection has pressurized males to send their genes into the future by mating with multiple females because of lower cost involved. sexuality. ___________________________________ ___________________________________ ___________________________________ But females because of higher costs involved with pregnancy and nursing select one mature and caring male.
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___________________________________ Mating Preferences
___________________________________ In order for males to pass their genes into future they look for youthful appearance in females. Females on the other hand look for maturity, dominance, affluence and boldness in males. ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Data based on 37 cultures. 31
OBJECTIVE 6‐14| Summarize the criticisms of Critiquing the Evolutionary Perspective
evolutionary explanations of human behavior, and describe the evolutionary psychologists’ Evolutionary psychologists take a behavior and work
backward to explain it in terms of natural selection.
responses to those criticisms. Evolutionary psychology proposes genetic determinism
and undercuts morality in establishing society.
___________________________________ Where genders are unequal, gender preferences are
wide, but closely equal, preferences narrow down.
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___________________________________ Evolutionary Psychologists Reply
___________________________________ Evolutionary psychologists argue that we need to test
behaviors that expound evolutionary principles.
___________________________________ ___________________________________ Evolutionary psychologists remind us how we have
adapted, but does not dictate how we ought to be.
___________________________________ Males and females are more alike than different, if we
study these differences we can establish their causes.
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