3Nature, Nurture, and Human Diversity Behavior Genetics: Predicting Individual DifferencesGenes: Our Codes for LifeTwin StudiesTemperament StudiesHeritabilityGene-Environment InteractionThe New Frontier: Molecular Genetics
4Nature, Nurture, and Human Diversity Evolutionary Psychology: Understanding Human NatureNatural SelectionAn Evolutionary Explanation of Human SexualityCritiquing the Evolutionary Perspective
5Nature, Nurture, and Human Diversity Parents and PeersParents and Early ExperiencesPeer InfluenceCultural InfluencesVariations Across CulturesCulture and the Self
6Nature, Nurture, and Human Diversity Cultural InfluencesCulture and Child-RearingDevelopmental Similarities Across GroupsGender DevelopmentGender Similarities and Differences
7Nature, Nurture, and Human Diversity Gender DevelopmentThe Nature of GenderThe Nurture of GenderReflections on Nature and Nurture
8Nature, Nurture, and Human Diversity SimilaritiesDifferencesGenes: Same set of chromosomesGenes: Genetic anomalies may make us differentBiology: Organs and body functions sameBiology: May change during developmentBrain: Same brain architectureBrain: Asymmetry of brain across gendersBehaviors: Speak languageBehavior: Speak different languagesOBJECTIVE 1| Give examples of differences and similarities within the human family.
9Behavior Genetics: Predicting Individual Differences Behavior Geneticists study our differences and weigh the relative effects of heredity and environment.OBJECTIVE 2| Describe the type of questions that interest behavior geneticists.
10The Nature Argument (is sometimes compelling) This guy will never be….This guy!!!Why does Brad Pitt look the way he does?
12Genes: Our Codes for Life Chromosomes containing DNA (deoxyribonucleic acid) are situated in the nucleus of a cell.OBJECTIVE 3| Define chromosome, DNA, gene, and genome, and describe their relationships.
13Genes: Our Codes for Life Segments within DNA consist of genes that make proteins to determine our development.
14GenomeGenome is the set of complete instructions for making an organism, containing all the genes in that organism. Thus, the human genome makes us human, and the genome for drosophila makes it a common house fly.
15Twin BiologyStudying the effects of heredity and environment on two sets of twins, identical and fraternal, has come in handy.OBJECTIVE 4| Explain how identical and fraternal twins differ, and ways that behavior geneticists use twin studies to understand the effects of environment.
16Twins and ProceduresBehavior geneticists’ effects of shared and unique environments on total or partial genetic makeup.
19Personality, Intelligence Separated TwinsA number of studies compared identical twins raised separately from birth, or close thereafter, and found numerous similarities.Separated TwinsPersonality, IntelligenceAbilities, AttitudesInterests, FearsBrain Waves, Heart Rate
20Separated TwinsCritics of separated twin studies note that such similarities can be found between strangers. Researchers point out that differences between fraternal twins are greater than identical twins.Bob Sacha
22Adoption StudiesAdoption studies, as opposed to twin studies, suggest that adoptees (who may be biologically unrelated) tend to be different from their adoptive parents and siblings.OBJECTIVE 5| Cite ways that behavior geneticists use adoption studies to understand the effects of environment and heredity.
23Adoptive StudiesAdoptive 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 of their genes?Ultimate question: Does parenting have an effect?
24Parenting Influences children’s Parenting does have an effect on biologically related and unrelated children.Parenting Influences children’sAttitudes, ValuesManners, BeliefsFaith, Politics
25Twin Studies: The results To summarize the countless amount of studies: twins (especially identical), whether or not they are raised in the same environment are very much alike in many ways.
26Temperament StudiesTemperament refers to a person’s stable emotional reactivity and intensity. Identical twins express similar temperaments, suggesting heredity predisposes temperament.OBJECTIVE 6| Discuss how the relative stability of our temperament illustrates the influence of heredity on development.
27Temperament StudiesA person’s characteristic emotional reactivity and intensity.They remain relatively stable over time.
28HeritabilityHeritability refers to the extent to which the differences among people are attributable to genes.OBJECTIVE 7| Explain heritablity’s application on individuals and groups, and explain what we mean when we say genes are self-regulating.
29HeritabilityThe proportion of variation among individuals that we can attribute to genes.It is a mathematical formula.Mark Twain explains it best using the barrel example.
30Group DifferencesIf 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 were a century ago.
31Nature and NurtureSome human traits are fixed, such as having two eyes. However, most psychological traits are liable to change with environmental experience.Genes provide choices for the organism to change its form or traits when environmental variables change. Therefore, genes are pliable or self-regulating.
32Gene-Environment Interaction Genes can influence traits which affect responses, and environment can affect gene activity.A genetic predisposition that makes a child restless and hyperactive evokes an angry response from his parents. A stressful environment can trigger genes to manufacture neurotransmitters leading to depression.OBJECTIVE 8| Give and example of a genetically influenced trait that can evoke responses in others, and give another example of an environment that can trigger gene activity.
33Gene-Environment Interaction Genes and environment affect our traits individually, but more important are their interactive effects.Alessia Pierdomenico/Reuters/CorbisRex FeaturesPeople respond differently toRowan Atkinson (Mr. Bean) than Orlando bloom.
34The study of the power and limitations of genes on who we are. Behavior GeneticsThe study of the power and limitations of genes on who we are.
35The New Frontier: Molecular Genetics Molecular genetics is a branch extension of behavior genetics that asks the question, “Do genes influence behavior?”OBJECTIVE 9| Identify the potential promise and perils of molecular genetics.
36Molecular 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 in which the fetus is suspected of having such disorders.However, this opens up a real concern regarding ethical issues involving such choices.
37Genetic Influences on Behavior Naturev.NurtureGenetic Influences on Behavior
38The Nature Argument (is sometimes compelling) This guy will never be….This guy!!!Why does Brad Pitt look the way he does?
44Evolutionary Psychology: Explaining Universal Behaviors Evolutionary psychology is the science that seeks to explain why humans act the way they do.Evolutionary psychology seeks to reconstruct problems that our ancestors faced in their primitive environments, and the problem-solving mechanisms they created to meet those particular challenges.From these reconstructed problem-solving adaptations, the science then attempts to establish the common roots of our ancestral behavior, and how those common behavioral roots are manifested today in the widely scattered cultures of the planet.The goal is to understand human behavior that is universally aimed at the passing of one's genes into the next generation.
45Evolutionary Psychology: Understanding Human Nature 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.OBJECTIVE 10| Describe the areas of psychology that interests evolutionary psychologists
46Natural SelectionNatural selection is an evolutionary process through which adaptive traits are passed on to ongoing generations because these traits help animals survive and reproduce.OBJECTIVE 11| State the principle of natural selection, and point out some possible effects of natural selection in the development of human characteristics.
47Natural Selection at Work 1959 Russian Fox story40 Males, 100 Females- mated- then kept only tamest of bunch.Mated the tames.40 years laterNew Breed of Fox
48Evolutionary Psychology at Work If we wanted to create a whole population of brainy teachers, we could take some teachers like…Have them mate.Then have the brainiest offspring mate amongst each other, and for countless generations keep doing the same thing.After 200 years, what would the population be like or what are the chances that the 40th generation of offspring be brainy.
49Look at our Behaviors…Can you answer these questions using evolutionary psychology?Why do infants fear strangers when they become mobile?Why are most parents devoted to their children?Why do we divide people into categories?Why do we have more phobias about spiders and snakes than electricity and nuclear weapons?Now, the big one?
50Human TraitsA 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?
52Question (summarized) Human SexualityGender Differences in SexualityMales and females, to a large extent, behave and think similarly. Differences in sexes arise in regards to reproductive behaviors.Question (summarized)MaleFemaleCasual sex60%35%Sex for affection25%48%Think about sex everyday54%19%OBJECTIVE 12| Identify gender differences in sexuality.
58Mating PreferencesNatural selection has caused males to send their genes into the future by mating with multiple females since males have lower costs involved.However, females select one mature and caring male because of the higher costs involved with pregnancy and nursing.OBJECTIVE 13| Describe evolutionary explanations for gender differences in sexuality.
59Mating PreferencesMales look for youthful appearing females in order to pass their genes into the future. Females, on the other, hand look for maturity, dominance, affluence and boldness in males.Data based on 37 cultures.
60Critiquing the Evolutionary Perspective Evolutionary psychologists take a behavior and work backward to explain it in terms of natural selection.Evolutionary psychology proposes genetic determinism and undercuts morality in establishing society.OBJECTIVE 14| Summarize the criticisms of evolutionary explanations of human behavior, and describe the evolutionary psychologists’ responses to those criticisms.Where genders are unequal, gender preferences are wide, but when they are closely equal, preferences narrow down.
61Evolutionary Psychologists Reply Evolutionary psychologists argue that we need to test behaviors that expound evolutionary principles.Evolutionary psychologists remind us how we have adapted, but do not dictate how we ought to be.Males and females are more alike than different, and if we study these differences we can establish their causes.
62Nature v. Nurture What do you think so far? Does Nature and Nurture interact and grow off of each other?Lets find out soon by examining Nurture in detail….
65Types of Environmental Influences ParentsPrenatalExperiencePeer InfluenceCultureGender
66How Much Credit ( or Blame ) Do Parents Deserve? You and your siblings grow up in the same environment, are you all the same?Parents effect your belief systems and values much more than your personality.Parents take too much credit for success and too much blame for failures.Extreme environmentalism can be VERY dangerous, why?Are children clay to be molded by their parents?
67Lets look at perhaps our first environmental influence…. Prenatal Environment
72Experience and Brain Development Early postnatal experiences affect brain development. Rosenzweig et al. (1984) showed that rats raised in enriched environments developed thicker cortices than those in impoverished environment.OBJECTIVE 16| Describe how experience can modify the brain.
73What does this mean for humans? If children from impoverished environments given stimulating infant care, they score better on intelligence tests by age 12 than counterparts.Use it or lose it
74A Trained BrainA well-learned finger-tapping task activates more motor cortex neurons (right) than were active in the same brain before training (left)
75Perhaps the biggest environmental influence, at least by your age may be…. Peer InfluenceI can’t get Sammy to clean up his toys, but when he sees his friends clean up in school, he jumps to it.“Selection effect” we seek out people with similar interests- that may explain why we seem to conform to our peers.
76CultureBehaviors, attitudes, traditions etc… of a large group that have been passed down from one generation to the next.
77Variation Over TimeCultures change over time. The rate of this change may be extremely fast. In many Western countries, culture has rapidly changed over the past 40 years or so.OBJECTIVE 21| Explain why changes in the human gene pool cannot account for culture over time.This change cannot be attributed to changes in the human gene pool because genes evolve very slowly.
78Greetings exerciseCultural VariationsTo understand how cultures effect who we are it is important to recognize our cultural norms: an understood rule for acceptable behavior.Individual v. Collectivistic CulturesWhy is it so hard to identify our own cultural norms?
79Variations over TimeDifferent generations of the same culture may also have differing norms.
80Memesself-replicating ideas, fashions or innovations passed from person to person.Budweiser FrogsWhere’s theBeef Lady.Toys R Us Theme Song
81Culture and the SelfIf a culture nurtures an individual’s personal identity, it is said to be individualist, but if a group identity is favored then the culture is described as collectivist.OBJECTIVE 22| Identify some ways a primarily individualist culture differs from a primarily collectivist culture, and compare their effects on personal identity.Kyodo News
83Culture and Child-Rearing Individualist cultures (European) raise their children as independent individuals whereas collectivist cultures (Asian) raise their children as interdependent.OBJECTIVE 23| Describe some ways that child-rearing differs in individualist and collectivist cultures.Jose Luis Palaez, Inc./ Corbis
84Culture and Child-Rearing Westernized CulturesAsian-African CulturesResponsible for your selfResponsible to groupFollow your consciencePriority to obedienceDiscover your giftsBe true to family-selfBe true to yourselfBe loyal to your groupBe independentBe interdependent
85Developmental Similarities Across Groups Despite diverse cultural backgrounds, humans are more similar than different in many ways. We share the same genetic profile, life cycle, capacity for language, and biological needs.OBJECTIVE 24| Describe some ways that humans are similar, despite their cultural differences.Copyright Steve Reehl
86Gender DevelopmentBased on genetic makeup, males and females are alike, since the majority of our inherited genes (45 chromosomes are unisex) are similar.OBJECTIVE 25| List one way males and females are similar, and other ways they differ.Males and females differ biologically in body fat, muscle, height, onset of puberty, and life expectancy.
87Biology of SexBiological sex is determined by the twenty-third pair of chromosomes. If the pair is XX, a female is produced. If the pair is XY, a male child is produced.OBJECTIVE 29| Explain how biological sex is determined, and describe the role of sex hormones in biological development and gender differences.
88Sexual Differentiation In the mother’s womb, the male fetus is exposed to testosterone (because of the Y chromosome), which leads to the development of male genitalia.If low levels of testosterone are released in the uterus, the result is a female.
90Gender We already know the nature differences. XX v XY But that focuses on SEX:We are going to discuss GENDER: What is the difference?
91Gender Differences in Aggression Men express themselves and behave in more aggressive ways than do women. This aggression gender gap appears in many cultures and at various ages.OBJECTIVE 26| Summarize gender gap in aggression.In males, the nature of this aggression is physical.
92Gender and Social Power In most societies, men are socially dominant and are perceived as such.In 2005, men accounted for 84% of the governing parliaments.OBJECTIVE 27| Describe some gender differences in social power.
93Gender Differences and Connectedness Young and old, women form more connections (friendships) with people than do men. Men emphasize freedom and self-reliance.OBJECTIVE 28| Discuss gender differences in connectedness, or the ability to “tend and befriend.”Oliver Eltinger/ Zefa/ CorbisDex Image/ Getty Images
94Gender Roles A set of expected behaviors for males and females List some of your gender roles.What gender role is she breaking?
98Gender Roles: Theories Gender Schema Theory suggests that we learn a cultural “recipe” of how to be a male or a female, which influences our gender- based perceptions and behaviors.Social Learning Theory proposes that we learn gender behavior like any other behavior—reinforcement, punishment, and observation.
99Social Learning Theory Lets use Sammy as an example.
100Social Learning Theory I play Baseball.Sammy imitates my behavior.I reward Sammy.Sammy’s Momputs on makeup.I punish Sammy.Sammy copies her.
101Gender Schema TheorySchema: a concept or framework of how we organize information.Develop schemas for gender.See the world through the lens of your gender schemas.Boy’s don’t do this,that’s for girls.Yeah, that’s cool!!!!I want to do that.