ANTH 330 FINAL
Blurton Jones & Konner "!Kung Knowledge of Animal Behavior" Goal of Study?
Goal of Study: determine how much the !Kung know about animal behavior, how they acquire that knowledge, & how accurate their knowledge is
Blurton Jones et al
Hadza children forage a lot, !Kung do not -costs & risks of allowing !Kung children to forage greatly outweigh benefits
Argument in support of the Embodied Capital Hypothesis
Individuals who shared accurate, useful info w/ close kin would've increased their kin's chances of surviving & reproducing, thereby increasing the representation of their genes in subsequent generations -language
Argument in support of By-Product Hypothesis
Martu children's hunting strategies: if children are capable of contributing to their subsistence, then it doesn't take long to learn how to forage. -challenges the claim that prolonged childhood evolved for learning
Transmission of ecological knowledge of Tareumiut & Nunamuit?
They used social norms/rules to cope with subsistence stress and this info was transmitted via oral tradition
What was the aim of Gwich'in Words About the Land?
To document traditional knowledge about wildlife species used by the Gwich'in before it is lost.
Gurven et al.
a test of the embodied capital hypothesis -several components of hunting success analyzed to determine relative impact of strength & skill on hunting ability RESULTS: as predicted by EC, indirect encounters peak earliest, followed by direct encounters rates, kill rates, & return rates
Mer children begin spearfishing...
as toddlers, but don't reach the same efficiency as the most practiced adult until age 10-14
some groups reduce the chances of subsistence stress is?
by controlling the availability of resources -timing, distribution, quantity -ex: regular setting of fires (prescribed burning)
Waorani boys can...
consistently hit leaf & fruit targets w/ a blowgun at age 5, but don't become proficient until their late teens
Social Intelligence Hypothesis for Encephalization & Prolonged Childhood
encephalization & prolonged childhood were driven by demand of predicting & manipulating behavior of conspecifics
Embodied Capital Hypothesis for Encephalization & Prolonged Childhood
extended juvenile period & large brain co-evolved w/ exploitation of nutrient-dense resources using complex extraction techniques
readily gathered resources
foods that can be obtained & eaten by simply gathering them from the environment -ex: fruit
Effects of burning on animal populations (doves)
greater in burned areas
Why does height matter?
height is a significant predictor of walking speed -this may account for the fact that given the choice, children choose to hunt in the rocky outcrops rather than the sandhills
Cultural transmission among Aka foragers: what is the question being addressed?
how much knowledge foragers acquire through social learning, & age by which different skill/knowledge sets are acquired?
The "Bailey Effect"
individuals are more likely to provide food & support to temporarily disabled individuals who have strong reputations for being generous & who are high producers
risk of extending childhood
it postpones sexual maturity & delays reproduction, thereby increasing the odds that an individual will die before reproducing
hunted resources
mobile resources that must be caught & processed before consumption
Sugiyama's Hypothesis
mortality in humans was reduced, in part, by food provisioning during periods of health crisis
extracted resources
non-mobile resources that must be removed from a protective context -ex: honey
The Karok burned...
oak groves to kill pests & disease, remove underbrush to make acorn collecting easier, & to roast acorns
Effects of burning on animal populations (jack rabbit)
population 2-4.5 times greater in burned areas
Effects of burning on animal populations (valley quail)
population 2.5 times greater in burned areas
By-Product Hypothesis for Encephalization & Prolonged Childhood
prolonged juvenility is a by-product of selection for larger body size: benefits of larger body size outweigh costs of longer growth period
Cultural transmission among Aka foragers: goal of study?
provide quantitative data on transmission of daily life skills in forager societies: specifically, to identify who transmits what skills to whom
What does Bird & Bliege-Bird's study tell us about forager children?
they argue that their data support the claim that prolonged juvenility evolved for reasons other than learning complex hunting strategies
Yanomamo children are...
"accomplished naturalists" at an early age -ex: most 12yo boys can name 20 species of bees
Result of Sugiyama's tests
-70% of health insults reported wouldn't be detectable from osteological evidence -supports claim that osteological evidence under-represents incidence of disabling illness/injury -16% of the village suffered a disability lasting longer than 7 days
Animal Knowledge Used by Foragers: BEHAVIOR
-On winter & spring mornings caribou are stiff from inactivity & easier to hunt -caribou are always on guard at night, some keep watch while others sleep & if something approaches, guard caribou take off & herd follows
Info Cues Used by Foragers: ANIMAL/PLANT CUES
-Ptarmigan eat berries in mtns but move into river valleys to avoid migrating caribou so the presence of ptarmigan in river valleys indicates caribou are arriving -grass sprouting by lakes indicates arrival of caribou
useful info to have for wayfinding
-alternative routes, short cuts -hiding places -defensive positions -vantage points -routes that are hard to track -terrain thats difficult to traverse unless you know the route -terrain obstacles -seasonal variation in terrain
Characteristics of the Transformer character
-ancestral being that was anthropomorphic -has supernatural powers -transformed the world into its present day form
The ability to manipulate one's environment offers a huge fitness advantage
-animals have to move to where the food is -an organism that can manipulate its environment can hang on and wait out the period of scarcity
other uses of burning
-at least 35 tribes used fire to increase yield of seeds -22 tribes used fire to promote tobacco growth -burned hazelnut flats to promote growth of new shoots for baskets -protection from snakes
benefits of burning prairies & meadows
-attracted game -preheated the ground which promoted early growth -easier travel -increased berry production -available sources of firewood -reduced black fly & mosquito concentrations -reduced fire hazard
Animal Knowledge Used by Foragers: POP FLUCTUATIONS & DISTRIBUTIONS
-before 1940s, there were no caribou in region, but now there are many -people note good places to hunt caribou -caribou don't return to same area the following year but wait until their food grows back
Koyukon Hunters
-believe that if they treat an animal they have killed w/ respect & gratitude it will be reborn for them to kill another day -tell stories set in "Myth Time"
Info Cues Used by Foragers: VEGETATION
-bits of moss dug up & scattered around indicate caribou feeding area - if sign is old, moss will be dry, if sign is fresh moss will be moist -in summer, grass that caribou walk on turns yellow & dries up after 2 days, so grass will be green if track is fresh -from Aug-Oct white rub marks can be found on trees/bushes where caribou rub velvet off their antlers
Animal Knowledge Used by Foragers: TRAITS
-can hear snowshoes creaking or parka brushing a branch from far away -mature bulls have largest & cows have smallest antlers
Info Cues Used by Foragers: TERRAIN
-caribou "often feed together in one area, leaving behind many pits where they dug for lichens & beds in snow where they slept" -caribou "leave wide summer & winter trails cut deeply into the ground, esp at river or creek crossing"
Animal Knowledge Used by Foragers: HAZARDS
-caribou charge straight ahead with head down & antlers to the ground -if hunter stands still & then steps aside when caribou is close it will run past him
Info Cues Used by Foragers: WEATHER CUES
-caribou easily spooked in fog -caribou monitor wind direction & smell for approaching danger -when they smell danger they look in direction of scent & move away from it -in fall, strong coastal winds compact the snow, making it difficult for caribou to dig for food -when snow becomes too hard to dig for food, caribou move to mtn slopes
Animal Knowledge Used by Foragers: INTER-SPECIES RELATIONSHIPS
-caribou eat muskrat houses in winter -ravens follow caribou herds & feed on scraps left by predators -moose don't like to be around caribou
Animal Knowledge Used by Foragers: HABITAT/DIET
-caribou like to live where there is enough food, safety, & a view into distance -tend to stay where their food grows -in summer they eat grass along lake shores & in winter dig it up from under snow
Benefits of prescribed burning in CA & OR grasslands
-caused 2nd green-up of grasses after onset of autumn rains -provided fall & winter feed for game
The Gwich'in, !Kung, & Aka studies provide support for the hypothesis that...
-childhood evolved for learning & skill development -occupation of the foraging niche was made possible by social learning
How do foragers acquire animal knowledge -- esp children?
-children that were forearmed with info about dangerous animals would stand a better chance of avoiding such animals &/or escaping unharmed from encounters -thus, social learning would have increased offspring fitness by enabling children to acquire useful info: in the absences of an actual animal encounter & before the info is actually needed
!Kung's risk of social learning
-distinguish between data, hearsay, & speculation
Prescribed burning in CA (Sierra Nevada)
-every 8-12 yrs in the fall -burned accumulations of forest litter & young trees, which produced more varied & productive environment
piloting
-following a set of landmarks -dependent on knowing the positions of landmarks relative to one another, and how they appear from different angles & distances
Gurven et al.'s hypothesis
-food sharing may be a means of acquiring a reputation for generosity & high productivity -which may signal high productive ability & willingness to cooperate -beneficiaries will be motivated to provision a generous individual when they are sick or injured -thus it is for motivation of others
Effect of walking speed & prey density on foraging returns
-foraging in sandhills requires 2.3 times the time investment & 2.2 times more walking as rocky outcrop foraging for only 1.3 times as many calories per hour -adults walk faster than children, so their encounter & return rates in the sandhills are much higher
what can the fossil record tell us about the problem of health risk in human evolution?
-frequency, duration, & fitness effects of temporary disability are hard to estimate from osteological evidence alone -bones can provide some info about selection pressure from health risk, & whether or not individuals survived health insults that temporarily interfered with foraging
Prescribed burning in California & Oregon
-grasslands -Chaparral
Animal Knowledge Used by Foragers: PREY SELECTION
-hides best in Aug & Sept -during rut bulls lose their fat, their meat smells strong & tastes bad -caribou in Bluenose herd are larger than those in Porcupine herd & meat is more tender
Animal Knowledge Used by Forager: CAPTURE TECHNIQUES
-hunters lure caribou by rubbing 2 sticks together -ppl scare caribou toward entrance of surround by making wolf cries or setting trees on fire
benefits of burning reeds & grasses along lakeside margins
-improved nesting/feeding areas of ducks & geese -increased growth of roots, the favored food of muskrats (fur)
Gwich'in ecological knowledge
-includes attitudes regarding proper meat distribution & resource use -transmitted via oral tradition
possible explanations for reduced mortality
-increasingly effective use of weapons (predation) -slow growth & adult protection that insulates juveniles from foraging competition -slow growth & adult protection that insulates juveniles from potentially lethal mating competition w/ adults -increased investment in immune function & in pathogen & parasite resistance -care & provisioning of sick/injured individuals
most frequent health insults
-lacerations -infections -bites & stings -puncture wounds -abrasions -pain -broken bones -burns -males suffered more illnesses than females
Human Life History is characterized by:
-long lifespan -extended period of juvenile dependency -resource transfers from adults to juveniles & between adults (food sharing) -encephalization & highly developed capacities for learning, planning & insight/innovation
Benefits of prescribed burning in CA & OR Chaparral
-maintained openings in brush on slopes, encouraging new growth, & created a more mixed combination of grasses -attracted deer -prevented expansion of brush into wooded grasslands
Prescribed burning in CA (Coast Range)
-meadows maintained by annual fall burning -undergrowth was burned regularly to make travel easier & prevent the forest from choking out useful plants
problems with studies of children's foraging
-measuring children's contributions to their subsistence in calories doesn't indicate whether children's foraging returns meet their nutritional needs
Info Cues Used by Foragers: TRACKS
-moose tracks are pointed at front end, caribou tracks are rounded at front end -caribou take smaller steps than moose -in winter, fresh caribou tracks won't be frozen
info acquisition for wayfinding
-personal experience: high energy and time costs limit amount of info one person can acquire -info exchange: exponentially increase amount of info a person can accumulate & rate of accumulation; enables individuals to learn about places they would otherwise never know about
burning in northern Alberta
-prairies & meadows -reeds and grasses along lakeside margins -streamside habitats & sloughs -windfall forests
dead reckoning
-present position is calculated using the angle of change from one's starting point -angle of change from starting point & distance traveled are calculated using velocity & acceleration info
benefits of burning streamside habitats & sloughs
-provided more grassland & forest edge, preferred habitat for moose
cognitive mapping
-referencing a visual mental representation of the relative positions of a set of points in space
benefits of burning windfall forests
-renewed and re-established plant & animal resources -reduced of summer wildfire -converted area to grassland (attract game)
cultural transmission among Aka foragers: methods
-researchers generated a list of 50 daily life skills -asked participants whether they possessed each skill & who taught them
Conclusion of Sugiyama's tests
-results show that provisioning of sick/injured individuals effectively lowers mortality in the population -healthcare provisioning has large fitness benefits for recipients -findings support the hypothesis that health risk is an adaptive problem
Info Cues Used by Foragers: SOUNDS
-rutting bulls make snorting sounds -caribou feet make unique clicking sound
Knowledge demands of prescribed burning
-seasonality -frequency -techniques of fire control
cultural transmission among Aka foragers: results
-self taught (0.9 %) -learned from parents (80.7 % for all skills combined) -shows that degree to which foragers acquire knowledge from others is high -many daily life skills are acquired in childhood, w/ majority acquired by adolescence -findings support EC hypothesis; contradicts GH claim
Songlines
-series of songs that follow the route & direction of travel of a dreamtime ancestor, as well as the course of their activities -has geographical referent -has proper sequence
The Dreamtime
-set of beliefs common to many Australian aboriginal peoples -refers to an indeterminate period of time when the world was shaped by ancestral beings -dreamtime beings are anthropomorphic -dreamtime beings are part human, part god -they created present day land formations -is both the past & present
What's the solution to the health risk problem?
-show-off hypothesis: Hawkes argues that men share meat to attract sexual partners ^doesn't work
Use of prescribed burning in Australia
-some areas were burned several times a year -grasses were burned to trigger 2nd green-up to attract game -also set to create different plant succession stages along travel routes between campsites
constraints on children's skill & knowledge acquisition
-some skills can't be taught until child has sufficient stamina to travel long distances, sufficient patience to endure discomfort, sufficient strength to manage heavy loads or animals, &/or cognitive & emotional maturity to exercise good judgment
!Kung's evolved interest in animal behavior
-sometimes observe animals more than is necessary for the purpose of the hunt -Gwich'in exhibit same tendency -BJ&K think that curiosity about animal behavior might be an adaptation
BJ & K Conclusion?
-the !Kung acquire knowledge in large part through oral tradition -information transmission via storytelling is common in forager cultures
!Kung descriptions of animal behavior
-they enjoy lengthy, detailed, gripping descriptions of events they've seen -kudu fights & kudu infant sleeping away from mother -accurate imitations: kudu fighting, snorting sounds
examples of resource management
-upper Tanana Indians hunted moose and would set fire to grasses to grow more for the moose -Mardudjara carried fire sticks to light vegetation on fire to promote the growth of other vegetation
Prescribed burning on the northern great plains
-used to control distribution of bison populations -short grass prairies burned in fall -parkland grasses burned in spring
Winnebago stories are divided into what?
-waikan (what is sacred): referred to a past in which events occurred that are no longer possible -worak (what is recounted): dealt w/ ordinary, present-day events & conditions
Effects of burning on animal populations (deer)
-weight was higher in burned areas -ovulation rate higher in burned areas -summer population higher in burned areas
techniques of fire control
-wind speed & direction -temp -dewpoint -relative humidities of adjacent foliage -time of day -size of area to be burned -slope -natural & man-made fire breaks -backfires -placement of people
ways in which humans cooperate as complex resource extraction techniques (4)
1. cooperative game drives used to acquire resources more efficiently 2. trade used to acquire resources from other ecological zones 3. marriage used to establish kin ties to people in other territories/ecological zones 4. food sharing & gift giving used to motivate others to reciprocate when needed
humans use what 3 methods for navigating
1. dead reckoning 2. cognitive mapping 3. piloting
Why do Martu adults & children make different foraging choices?
1. difference caused by difficulty of learning how to hunt sandhill patches compared to rocky outcrops 2. difference is caused by size constraints RESULTS: Height, not age, matters!
To make a living as a forager in the Arctic, a person needs to know: (5)
1. how to make & use clothes, snow houses, lamps, harpoons, bows, kayaks, etc 2. how to predict storms 3. the habits of animals, esp game species & predators 4. how to manage dogs 5. how to travel safely on ice
When looking at children's foraging, its important to consider
1. nutritional value of resources acquired 2. easy-to-extract resources vs. difficult-to-extract resources 3. safe, easily navigable habitats vs. dangerous, difficult-to-navigate habitats 4. foraging in the company of adults vs. unattended by adults
How was Gwich'in Words About the Land conducted?
198 interviews were conducted with 46 elders, fishermen, & trappers. Participants were asked 60 questions regarding the animal's behavior, distinguished characteristics, habitat, life history, & utilization. (about 22 diff species)
proportion of extracted resources in forager diet
32%
proportion of hunted resources in forager diet
60%
proportion of readily gathered resources in forager diet
8%
How was occupation of the foraging niche made possible?
By the ability to learn from others
