lecture 27 Flashcards
4 Approaches (Sociobiology?)
Memetics, Dual Inheritance Theory, Evolutionary Psychology, Human Behavioral Ecology
Meme
basic unit of cultural transmission, an element of culture that can be passed on by non-genetic means; examples: fashion, science/research, literature, music
Mimetics
Science that studies the replication, spread, and evolution of memes
Religion studies
Positive correlation between degree of religiosity and number of offspring produced; also positive correlation between belief in religious ideas and number of offspring; seems to portray a mutualistic relationship of religion because increases fitness of individuals and increases spread of religious beliefs (benefits meme)
Dual Inheritance Theory
aim is to reveal mechanisms by which cultural info is transmitted and examine how genetics and culture influence behavior; Assumptions: Cultural inheritance, multiple forces, modeling, co-determination
Evolutionary Psychology
Study of the adaptive significance of behavior; views the mind as a structure shaped by natural selection to solve problems faced by our ancestors; We have a modular mind- different neural circuits designed for dealing with various adaptive problems were shaped by natural selection; consciousness is only the tip of the iceberg-most of mind is hidden; our brains were evolved to adapt to the environment of our ancestors, not adapted to our modern environment
Environment of Evolutionary Adaptedness (EEA)
a time period at which evolution occurred for the adaption of a particular trait; this is the environment in which the human brain or body evolved in response to specific environmental pressures of that time
Human Behavioral Ecology
Aim to trace the link between ecological factors and adaptive behavior; take a piecemeal approach where complex behavior is studied piece by piece; use models to generate testable hypotheses
4 Caveats to studying human behavior
- Humans don’t consciously do things to increase inclusive fitness 2. Adaptive behaviors are not necessarily morally right 3. saying a behavior is adaptive doesn’t mean it is genetically determined 4. not all human behavior is adaptive in modern society, but may have been adaptive for ancestors
Why is studying human behavior useful?
- Selection maximizes fitness, not happiness 2. Understanding more about our behavior may allow us to make happier choices
Penis and testicle size in primates
Male gorillas who dominant a harem of females have smaller testes; polygamous male chimps compete for females and have larger testes (more sperm); human testes more similar in size to polygamous species, suggesting that ancestors were polygamous (while some were serial monogamous)
Studies showing that females and males have different goals and expectations for mating
Males expected a greater number of partners throughout a lifetime compared to females; males rated a higher likelihood of having sexual intercourse with their partners, particularly noticeable difference a short time after previous sex- females rate low probability soon after sex
Partner intelligence study
particularly for casual sex, males rated lower minimum acceptable intelligence that they desired in someone they were to have sex with; similar intelligence desires when looking for steady date or marriage partner
Preferred age of partner
Females tended to want older males (more resources), while males wanted partners younger than themselves- other study shows that males with younger partner had more offspring; also, for older age group- correlation between income and ability to have non-protected sex (may be why females seek older men)
Sexual selection/parental investment theory
females should seek males who demonstrate ability and willingness to contribute to a relationship; males should place high emphasis on female fertility- and seek info concerning youth, attractiveness, fertility; Study shows that females do seek resources and offer attractiveness while males offer resources and seek attractiveness
Correlation between “attractive traits” and fertility
females with narrow waist and large breasts secreted more estrogen, which is a measure of increased fertility
Masculinity of face shape study
females with high conception risk (able to become pregnant) preferred males with more masculine face compared to females of low conception risk who showed less preference for masculinity
Fertility and unfaithfulness
when females are most fertile, seek more extra pair copulations (with males other than partner), while females that are least fertile seek more intra pair copulations
Attraction to partner or extra-pair men as function of partner asymmetry
the higher degree of partner asymmetry, the lower attraction of female to the male partner and the increased attraction to extra-pair males
Ejaculate amount and partner separation
more sperm is released after longer separation period (maybe an evolved mechanism of sperm competition)
assumptions of dual inheritance theory
- cultural inheritance- culture is acquired socially; 2. Multiple forces affect spread of culture; 3. Modeling can be used to show culture and its spread; 4. Co-determination-human behavior is shaped by genetic and cultural influences
assumptions of human behavioral ecology
- behavior can be explained through question: what are ecological forces that select for behavior?
- Piecemeal approach-complex behavior can be studied piece by piece; 3. Models can produce testable hypotheses; 4. Conditional strategies- decisions made based on current conditions; 5. Phenotypic gambit- it’s ok to forget gene complexities and focus on the behavior
