EEB 3002 Exam 2 Material

• The Blank Slate


  John Locke

  
  

  Tabula rasa

  
  

  Individuals are born without pre-programming and are instead shaped by learning and experience

  
  

  "Nurture" instead of "nature"
• Alfred Kroeber


  Argued "superorganic" aspect of humans separates them from animals. Biology determines the body but the brain is determined by culture.
• brain size and learning


  Humans have big brains

  
  

  The areas that are especially big in humans are those that are good at learning... ex: cerebral cortex

  
  

  Much of what we know we learn from others
• human universals that also have variations (examples from class)


  language

  
  

  gestures

  
  

  food preferences

  
  

  standards of beauty
• human lifestyle compared to other primates


  Compared to other primates, humans live in a limited range of societies

  
  

  In no human society do people regularly live like our ape relatives
• Niko Tinbergen's Four Questions

  Proximate or mechanism

  - HOW does it work?

  
  

  Ultimate or function

  - WHY does it work that way?

  
  

  Ontogeny

  - HOW does it develop in the individual?

  
  

  Phylogeny

  - WHAT is its evolutionary history?
• Ethology


  Ethologists focused on the particular set of behaviors displayed by each species

  (The "ethogram")

  
  

  These behaviors were seen as the product of natural selection

  
  

  Each species had its own nature shaped by natural selection

  
  

  Desmond morris described humans as just another primate - the naked ape
• What does it mean for a trait to be a human universal?


  Features may be both universal but also variable

  
  

  Ex: all societies have language, but many different languages are spoken

  
  

  A feature may be "found among a people" without being present in every person

  
  

  Ex: Some form of marriage appears worldwide, but not every person marries
• example of a society "without marriage"


  "Walking marriage" among the Mosuo ethnic minority in china

  
  

  1. Partners do not live together

  
  

  2. Children raised by mother

  
  

  3. Male partner visits female partner at night

  
  

  Mosuo usually have only one partner at a time, based on mutual affection

  
  

  Most partnerships are long-term and may even last a lifetime

  
  

  Fathers of children are commonly known

  
  

  Whole systems seem to be relic of feudal past, where patriarchal, patrilineal upper class sought to weaken male inheritance among peasants.
• Mechanisms of Universals


  Diffusion of ancient, generally very useful cultural traits

  
  

  Ex: fire, cooking, tool-making, dogs

  
  

  Cultural reflection of physical facts

  
  

  Ex: in many languages, word for "pupil" of the eye means "little person" from seeing oneself reflected in others eye

  
  

  Operation, structure, and evolution of the human mind
• Group selection


  Vero copner wynee-edwards

  
  

  Animal dispersion in relation to social behavior

  
  

  Argued that much of animal social behavior evolved "for the good of the group"

  
  

  Group selection underlay much of ethology
• Sociobiology

  Based on theory developed by leading scholars

  
  

  Popularized by richard dawkins and E.O Wilson

  
  

  Focus on gene as the unit of selection

  
  

  Much "altruistic" behavior is done for the benefit of kin and is genetically self-interested

  
  

  Social behavior involves conflicts of interest between organisms with different levels of relatedness

  
  

  Game theory

  - Evolutionarily stable strategies (ESS) (Strategy that can't be invaded by mutants)
• Behavioral ecology


  Understanding animal behavior as adaptive strategies in response to ecological pressures

  
  

  Emerged from ethology and tinbergen's four questions

  
  

  Recognizes that organisms adjust their response according to their environment
• Evolutionary anthropology


  based on: Paleoanthropology

  Human behavioral ecology

  Life history theory

  Human biology

  Genetics

  Primatology
• Evolutionary psychology


  Built on "cognitive revolution" in psychology

  
  

  The adapted mind: evolutionary psychology and the generation of culture

  
  

  The brain contains cognitive mechanisms ("modules")

  
  

  These mechanisms can be shaped by natural selection, just like any other organ
• EEA

  Environment of evolutionary adaptedness: The environment to which a particular evolved mechanism is adapted

  
  

  specific to trait in question

  
  

  For human psychological mechanisms, often refers to the savannas of africa in the Pleistocene
• Hunter-Gatherers

  Genus Homo originate around 2.5 mya

  
  

  Modern homo sapiens originated 300,000 years ago

  
  

  Agriculture originated 10,000 years ago

  
  

  For 96% of the existence of modern homo sapiens, everyone was a hunter-gatherer
• World subsistence 2000 BC

  Most societies were hunter gatherers
• Hunter-gatherer societies

  Long-standing, ongoing debates about what typical hunter-gatherers were like

  
  

  Modern humans originated 300,000 years ago

  
  

  Dispersed from africa 50-100,000 years ago

  
  

  Settled throughout the world

  
  

  Everyone lived as hunter-gatherers until food plans were domesticated 10,000 years ago

  
  

  Hunter-gatherers lived in a wide range of climates, habitats, and societies
• Arctic hunter-gatherers


  The inuit expanded from alaska east to greenland around 1200-1300 AD, replacing older dorset culture

  
  

  Living in the arctic requires sophisticated technology:

  
  

  1. Warm, waterproof clothing

  
  

  2. Toggle harpoons for hunting whales, seals

  
  

  3. Seaworthy boats

  
  

  4. Dogsleds

  
  

  5. Warm shelters in treeless land
• Northwest coast of north america

  Hunted salmon which have a weird lifestyle so it shaped their living situation
• Sedentary hunter-gatherers


  Salmon runs provided reliable resource

  
  

  Salmon was smoked and stored for steady food supply

  
  

  Permanent houses

  
  

  Frequent warfare

  
  

  Stratified society:

  
  

  1. Chief, aristocracy, commoners, slaves

  
  

  2. Luxury goods

  
  

  3. Potlatch
• Great plains of north america

  Hunting on foot

  
  

  Equestrian hunters

  
  

  1. Introduction of horse by spanish enabled native americans on the great plains to hunt buffalo more effectively

  
  

  2. Horse dramatically transformed societies

  
  

  - Faster travel

  - Larger camps

  - Highly mobile warriors
• The Hadza: "median hunter-gatherers"


  Many features of Hadza life are similar to what we

  expect life was like in EEA

  
  

  1. No permanent structures, horses, fishing, whaling

  
  

  Hadza are very conservative

  
  

  1. In many ways, much like they were when first described 80 years ago

  
  

  2. Compared to large sample of hunter-gatherers, Hadza are in middle range for many features
• Hadza compared to median foragers


  Compared to sample of 237 warm-weather, non-equestrian foragers

  Camp population

  
  

  Move similar times of year

  
  

  Hadza ethnic population is much higher

  
  

  hadza live in smaller area

  
  

  lower number of polygynous men in Hadza
• Hadza do not equal EEA because....

  Hadza have some tech that may be more recent

  
  

  1. Effective poisons for hunting big game

  
  

  Hadza today are surrounded by pastoralists and farmers and protected by national government

  
  

  On past and in world of hunter-gatherers warfare may have been more common
• hunter gatherer world diagram

  
• African hunter gatherers such as hadza provide key insights into

  more typical conditions of human evolution
• Developed sophisticated technology in response to

  local challenges and opportunities
• subsistence


  consumption to stay alive
• Sex differences in food production in chimpanzees

  In most other primates, males and females forage for the same foods

  
  

  chimpanzees will smash nuts with rocks which is a sign of tool use

  
  

  female champanzees termite fish with tools

  
  

  Chimpanzees snatch juvenile monkeys and they hunt them. Largest monkey so per hunt they get more - relates to optimal foraging theory. Do not have an adaptive response to chimpanzees.

  
  

  Hunts: usually done by multiple males. More likely to be successful with more individuals. They seem to take on more roles and help each other.

  
  

  There is meat sharing among chimpanzees - shared among individuals who are allies
• Sex differences in food production in bonobos


  hunting but more often done by females.
• key differences between chimpanzees and bonobos and how they hunt (sex differences)

  Chimpanzees:1. Males do most hunting bouts

  2. Females can and do hunt (F: 9-21% of hunts; even when carrying babies)

  3. But if they do, males often steal their prey

  4. Females do more extractive foraging (termite fishing and nut-cracking) and are more efficient than males

  Bonobos:1. Females hunt more frequently

  2. Females often rank higher than males and are less likely to experience thief
• Why do women usually gather?


  Anisogamy biases evolution toward sex differences in parental effort

  
  

  Female mammals are extreme specialists in parental care (internal gestation, lactation)

  
  

  primates are slow growing young that need to be carried

  
  

  They need reliable sources of sufficient food to feed selves and offspring

  
  

  Reproductive age women usually carrying a baby (increased cost of travel, increased risk of pursuing prey)
• Why is hunting usually done by men?


  With food subsidies from women, they are able to pursue a high risk, high reward strategy

  
  

  Weapons for fighting also used for hunting
• Human Behavioral Ecology

  Human behavior varies among different societies

  
  

  
  

  Variation is often a response to differences in ecology

  
  

  Are resources defendable?

  
  

  Can wealth be accumulated?

  
  

  Nomadic or sedentary?
• Adaptation


  Product of natural selection

  
  

  Takes multiple generations
• Adaptability


  Ability to cope with changes in environment

  
  

  Occurs within a single individual
• modes of subsistence


  foraging

  
  

  sedentary foragers

  
  

  horticulture

  
  

  pastoralism

  
  

  agriculture

  
  

  hunter-gatherers
• Foraging

  Hunting and gathering

  
  

  Only wild foods

  
  

  Great majority of human evolutionary history

  
  

  Mobile foragers:

  
  

  1. !Kung, Ache, Hadza, Unuit

  
  

  2. No permanent settlement

  
  

  3. Range nomadically within large home range

  
  

  4. Few possessions

  
  

  5. Little wealth

  
  

  6. Egalitarian

  
  

  7. Most marriages monogamous