Exam 2 Flashcards
What is optimal foraging theory? How successful is it in explaining foraging patterns?
- natural selection designed humans to maximize their rate of energy return relative to the amount of time they spend foraging
- research shows ppl make rational decisions much of the time - stop collecting a resource when it reduces the average rate of return for all resources combined
According to optimal foraging theory, what is search time, handling/processing time, opportunity costs?
- search time: time it takes to search for plants and animals to eat
- handling/processing time: time it takes to dig up,cut down plants, get them ready to eat; also includes time spent tracking, killing and butchering animals
- opportunity costs: time spent searching for one type of food leaves less time to find other types of food
What are the exceptions to optimal foraging theory? Do they make sense in light of evolution?
- strong preference for meat
- sometimes men pass on plants to hunt for game, even when rate of return is lower
- evolution explan: nutritional advantage to meat, way achieve status (hunters tend to have higher status leading to better mating opportunities)
What are the strategies ppl use to “make a living”?
- hunting/gathering: exclusive until about 10,000 yrsa ago, bands of no more than 100 individuals, frequent move camps, food storage rare
- cultivating crops
- herding animals
- making goods and selling them
How often do hunter gatherers move camp? Why is there variability in this?
- varies, depending on the region they inhabit (ex. 50x a year vs. 2x a year)
- also changing of the seasons and what resources are available to them
What percent of food comes from hunting? Gathering? How does it relate to latitude?
- latitude relates to the availability of diff types of food
- closer to equator about half from gathering (50-60ish)
- further from equator much more than half from hunting/fishing
- as latitude increases, reliance on hunting and fishing increases
In hunter-gatherer societies, who hunts and who gathers? Why?
- men do hunting, women gather
- why women don’t hunt: women much more important to survival of offspring (carry child, feed child, pregnancy) takes them away from child for period of time
What are the benefits of being a good hunter?
- aside from the nutritional advantage
- good hunters (men) have higher social status and are preferred as mates
What is the Provisioning Hypothesis?
- transition from foraging to large game hunting provided major impetus for human evolution including toolmaking & use, development of large brains, complex language used to communicate w/ other hunters
- meat is full of energy, benefits brought to men who provide meat for their families
What is the support for the provisioning hypothesis/ what does it explain?
- strong male coalitions
- reciprocal altruism & social exchange: help someone at cost to yourself and they may return the favor at another time
- division of labor: better for women to be with young children
- emergence of stone tools
What is the Showoff Hypothesis? What support is there for this idea?
- hypothesis: women prefer to have neighbors who are showoffs (go after rare large game, women benefit by getting some of the meat)
- women reward men who do this by favoring them, siding with them during disputes, having sex with them
- not all men good at hunting; takes years to perfect
- good hunters are preferred by women (higher social status preferred as mates; women may withhold sex if male doesnt bring home meat)
What is the Gathering Hypothesis? What is the benefit of this view? Can it explain as much as the provisioning hypothesis?
- hypothesis: securing plant food through use of stone tools provided the primary evolutionary impetus for the emergence of modern humans (hunting became important later)
- corrects view that centers solely on men
- accounts for primate relatives having diets coming mostly from foraging
- does not account for division of labor
Is the claim that hunter-gatherers are “affluent” (meaning they don’t have many needs) true?
- not true
- spend about 28 hrs foraging
- about 46 hrs a week of work (making/repairing tools/weapons, processing foods, fathering wood)
- ppl undernourished
- food anxiety
- high infant mortality rate
- infectious disease
When and where did agriculture develop? What plants and animals were domesticated?
- about 10,000-11,500 yrs ago in fertile crescent
- wheat, barley, rye, peas, lentils
- sheep, goats, cattle, pigs
What’s the possible adaptation for being sick during pregnancy?
- nausea & vomiting give protection from harmful effects of toxins and pathogens (vomiting expels pathogens; nausea learn to avoid)
- also encourage to avoid pathogenic food
What foods have the highest aversions for pregnant women?
- meat, eggs, coffee, alcohol, broccoli, brussel sprouts, cabbage
When are women sickest? What is the significance of this?
- sickest during 1st trimester
- significant bc fetus very vulnerable in this stage and mother’s immune system is vulnerable in this period (suppressed)
- progesterone stimulates decrease in NK cells
Do women feel only heightened disgust or are some good smells heightened as well?
- increased olfactory acuity overall
- find some odors less pleasant
- find some odors like fruit and flowers more pleasant
Why do moms lower their immune system during early pregnancy? What impact does this have on pregnancy sickness?
- early on immune system is suppressed bc body interprets fetus as foreign body therefore suppresses immune system to keep from attacking
- immune response at lowest level when women experience sickness
What does cross-cultural evidence show about pregnancy sickness?
- sickness appears to be widespread; in some cultures is the first outward sign of pregnancy recognized
- lower levels of sickness in places that eat less meat (meat often contains toxins)
