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Intensification, Tipping Points, and Social Change in a Coupled Forager-Resource System

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Abstract

This paper presents a stylized bioeconomic model of hunter-gatherer foraging effort designed to study the process of intensification on open-access resources. A critical insight derived from the model is that the very success of an adaptation at the level of an individual forager group can create system-level vulnerabilities that subsequently feed back to cause emergent social change. The model illustrates how the intensification of harvest time by individuals within a habitat creates a forager-resource system that becomes vulnerable to perturbations. When the system is vulnerable, it is characterized by two resource harvest equilibria: a sustainable, low-effort equilibrium and a degraded, high-effort equilibrium. In this situation, the forager-resource system can be shocked back and forth between these different equilibria by perturbations, generating considerable risk for foragers. We use the model to isolate the ecological conditions under which the instability of the system generates the risk that foragers will experience a shortfall of resources, and we suggest a mechanism that might lead foragers to adopt social institutions that regulate who can access a habitat as an adaptive response. As an illustration of the potential utility of the insights drawn from the model, comparisons are made with a substantial ethnographic data set.

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References

  • Anderies, J. M. (1998). Culture and human agro-ecosystem dynamics: the Tsembaga of New Guinea. Journal of Theoretical Biology, 192, 515–530.

    Article  Google Scholar 

  • Anderies, J. M. (2003). Economic development, demographics, and renewable resources: a dynamical systems approach. Environment and Development Economics, 8, 219–246.

    Google Scholar 

  • Anderies, J. M. (2006). Robustness, institutions and large-scale change in socio-ecological systems: the Hohokam of the Phoenix Basin. Journal of Institutional Economics, 2, 133–155.

    Article  Google Scholar 

  • Anderies, J. M., Jannsen, M. A., & Walker, B. H. (2002). Grazing management, resilience, and the dynamics of a fire-driven rangeland system. Ecosystems, 5, 23–44.

    Article  Google Scholar 

  • Baker, M. J. (2003). An equilibrium conflict model of land tenure in hunter-gatherer societies. Journal of Political Economy, 111, 124–173.

    Article  Google Scholar 

  • Bender, B. (1978). Gatherer to farmer: a social perspective. Journal of World Archaeology, 10, 204–222.

    Article  Google Scholar 

  • Bettinger, R. L. (1991). Hunter-gatherers: Archaeological and evolutionary theory. New York: Plenum.

    Google Scholar 

  • Bettinger, R. L. (1999). From traveler to processor: Regional trajectories of hunter-gatherer sedentism in the Inyo-Mono Region, California. In B. R. Billman & G. M. Feinman (Eds.), Settlement pattern studies in the Americas: Fifty years since Viru (pp. 39–55). Washington: Smithsonian.

    Google Scholar 

  • Bettinger, R. L., & Baumhoff, M. A. (1982). The Numic spread: Great Basin cultures in competition. American Antiquity, 47, 487–503.

    Article  Google Scholar 

  • Binford, L. R. (1983). In pursuit of the past: Decoding the archaeological record. New York: Thames and Hudson.

    Google Scholar 

  • Binford, L. R. (1999). Time as a clue to cause? Proceedings of the British Academy, 101, 1–35.

    Google Scholar 

  • Binford, L. R. (2001). Constructing frames of reference: An analytical method for archaeological theory building using hunter-gatherer and environmental data sets. Berkeley: University of California Press.

    Google Scholar 

  • Brander, J. A., & Taylor, M. S. (1998). The simple economics of Easter Island: A Ricardo-Malthus model of renewable resource use. American Economic Review, 88, 119–138.

    Google Scholar 

  • Cashdan, E. (1983). Territoriality among human foragers: Ecological models and an application to four Bushman groups. Current Anthropology, 24, 47–66.

    Article  Google Scholar 

  • Charnov, E. L. (1976). Optimal foraging, the marginal value theorem. Theoretical Population Biology, 9, 129–136.

    Article  Google Scholar 

  • Charnov, E. L., Orians, G. H., & Hyatt, K. (1976). Ecological implications of resource depression. American Naturalist, 10, 247–259.

    Google Scholar 

  • Clark, C. W. (1976). Mathematical bioeconomics: The optimal management of renewable resources. New York: Wiley.

    Google Scholar 

  • Clark, C. W., & Mangel, M. (2001). Dynamic state models in ecology. New York: Oxford University Press.

    Google Scholar 

  • Cohen, M. N. (1977). The food crisis in prehistory. New Haven: Yale University Press.

    Google Scholar 

  • Cohen, M. N. (2009). Introduction: rethinking the origins of agriculture. Current Anthropology, 50, 591–595.

    Article  Google Scholar 

  • Cowgill, G. L. (1975). On the causes and consequences of ancient and modern population changes. American Anthropologist, 77, 505–525.

    Article  Google Scholar 

  • Dielman, T. E. (2001). Applied regression analysis. Pacific Grove: Brooks and Cole.

    Google Scholar 

  • Dyson-Hudson, R., & Smith, E. A. (1978). Human territoriality: an ecological reassessment. American Anthropologist, 80, 21–41.

    Article  Google Scholar 

  • Ermentrout, B. (2006). XPPAUT 5.96 (Linux-Ubuntu distribution).

  • Gordon, H. S. (1954). The economic theory of a common property resource: the fishery. Journal of Political Economy, 62, 124–42.

    Article  Google Scholar 

  • Grove, M. (2009). Hunter-gatherer movement patterns: causes and constraints. Journal of Anthropological Archaeology, 28, 222–233.

    Article  Google Scholar 

  • Hassell, M. P., & Varley, G. C. (1969). New inductive population model for insect parasites and its bearing on biological control. Nature, 223, 1133–1137.

    Article  Google Scholar 

  • Hayden, B. (1995). A new overview of domestication. In: D. T. Price & A. B. Gebaure (Eds.), Last hunters–first farmers: New perspectives on the prehistoric transition to agriculture (pp. 273–299). Santa Fe: School of American Research Press.

  • Holt, R. D., & Kimbrell, T. (2007). Foraging and population dynamics. In D. W. Stephens, J. S. Brown, & R. C. Ydenberg (Eds.), Foraging: Behavior and ecology (pp. 365–395). Chicago: University of Chicago Press.

    Google Scholar 

  • Janssen, M. A., Kohler, T. A., & Scheffer, M. (2003). Sunk-cost effects and vulnerability to collapse in ancient societies. Current Anthropology, 44, 722–728.

    Article  Google Scholar 

  • Keeley, L. H. (1988). Hunter-gatherer economic complexity and population pressure: a cross-cultural analysis. Journal of Anthropological Archaeology, 7, 373–411.

    Article  Google Scholar 

  • Keeley, L. H. (1995). Protoagricultural practices among hunter-gatherers: a cross-cultural survey. In D. T. Price & A. B. Gebaure (Eds.), Last hunters-first farmers: New perspectives on the prehistoric transition to agriculture (pp. 243–272). Santa Fe: School of American Research Press.

    Google Scholar 

  • Kelly, R. L. (1995). The foraging spectrum: Diversity in hunter-gatherer lifeways. Washington: Smithsonian Institution Press.

    Google Scholar 

  • Lee, C. T., & Tuljapurkar, S. (2008). Population and prehistory I: food-dependent population growth in constant environments. Theoretical Population Biology, 73, 473–482.

    Article  Google Scholar 

  • MacArthur, R. H. (1972). Geographical ecology: Patterns in the distribution of species. New York: Harper and Row.

    Google Scholar 

  • MacArthur, R. H., & Pianka, E. R. (1966). On optimal use of a patchy environment. American Naturalist, 100, 603–609.

    Article  Google Scholar 

  • May, R. M. (1973). Stability and complexity in model ecosystems. Princeton: Princeton University Press.

    Google Scholar 

  • Minnis, P.E. (1992). Earliest plant cultivation in the desert borderlands of North America. In C. Wesley Cowan & Patty Jo Watson (Eds.), The origins of agriculture: An international perspective (pp. 121–141). Washington D.C.: Smithsonian Institution Press.

  • Odum, E. P., & Barrett, G. W. (2002). Fundamentals of ecology. New York: Thomson Learning.

    Google Scholar 

  • Ostrom, E. (2005). Understanding institutional diversity. Princeton: Princeton University Press.

    Google Scholar 

  • Pimm, S. L., & Lawton, J. H. (1978). On feeding on more than one trophic level. Nature, 275, 542–544.

    Article  Google Scholar 

  • Puleston, C. O., & Tuljapurkar, S. (2008). Population and prehistory II: space-limited human populations in constant environments. Theoretical Population Biology, 74, 147–160.

    Article  Google Scholar 

  • Redding, R. W. (1988). A general explanation of subsistence change: from hunting and gathering to food production. Journal of Anthropological Archaeology, 7, 56–97.

    Article  Google Scholar 

  • Rosenberg, M. (1990). The mother of invention: evolutionary theory, territoriality, and the origins of agriculture. American Anthropologist, 92, 399–415.

    Article  Google Scholar 

  • Rosenberg, M. (1998). Cheating at musical chairs: territoriality and sedentism in an evolutionary context. Current Anthropology, 39, 653–681.

    Article  Google Scholar 

  • Rosenzweig, M. L. (1968). Net primary productivity of terrestrial communities: prediction from climatological data. American Naturalist, 102, 67–74.

    Article  Google Scholar 

  • Schaefer, M. B. (1991). Some aspects of the dynamics of populations important to the management of commercial marine fisheries. Bulletin of Mathematical Biology, 53, 253–279.

    Google Scholar 

  • Scheffer, M., & Carpenter, S. R. (2003). Catastrophic regime shifts in ecosystems: linking theory to observation. TRENDS in Ecology and Evolution, 18, 648–656.

    Article  Google Scholar 

  • Smith, E. A. (1988). Risk and uncertainty in the “original affluent society”: evolutionary ecology of resource sharing and land tenure. In T. Ingold, D. Riches, & J. Woodburn (Eds.), Hunters and gatherers vol. I: History, evolution, and social change (pp. 222–251). Oxford: Berg.

    Google Scholar 

  • Smith, E. A. (1991). Inujjuamiut foraging strategies: Evolutionary ecology of an arctic hunting economy. Hawthorne: Gruyter.

    Google Scholar 

  • Stephens, D. W., & Krebs, J. R. (1986). Foraging theory. Princeton: Princeton University Press.

    Google Scholar 

  • van Coller, L. (1997). Automated techniques for the qualitative analysis of ecological models: continuous models. Conservation Ecology, 1(1), 5. Available online at http://www.consecol.org/vol1/iss1/art5/

  • Wills, W. H. (1988). Early prehistoric agriculture in the American Southwest. Santa Fe: SAR.

    Google Scholar 

  • Winterhalder, B. (1983). Opportunity-cost foraging models for stationary and mobile predators. American Naturalist, 122, 73–84.

    Article  Google Scholar 

  • Winterhalder, B. (2001). The behavioral ecology of hunter-gatherers. In C. Panter-Brick, R. H. Layton, & P. Rowley-Coney (Eds.), Hunter-gatherers: An interdisciplinary perspective (pp. 12–35). Cambridge: Cambridge University Press.

    Google Scholar 

  • Winterhalder, B. (2002). Models. In J. P. Hart & J. E. Terrell (Eds.), Darwin and archaeology: A handbook of key concepts (pp. 201–223). Westport: Bergin and Garvey.

    Google Scholar 

  • Winterhalder, B., & Goland, C. (1993). On population, foraging efficiency, and plant domestication. Current Anthropology, 34, 710–715.

    Article  Google Scholar 

  • Winterhalder, B., & Goland, C. (1997). An evolutionary ecology perspective on diet choice, risk, and plant domestication. In K. J. Gremillion (Ed.), People, plants, and landscapes: Studies in paleoethnobotany (pp. 123–160). Tuscaloosa: University of Alabama Press.

    Google Scholar 

  • Winterhalder, B., & Lu, F. (1997). A forager-resource population ecology model and implications for indigenous conservation. Conservation Biology, 11, 1354–1364.

    Article  Google Scholar 

  • Winterhalder, B., Baillargeon, W., Cappelletto, F., Daniel, R. I., & Prescott, C. (1988). The population ecology of hunter-gatherers and their prey. Journal of Anthropological Archaeology, 7, 289–328.

    Article  Google Scholar 

  • Wood, J. W. (1998). A theory of preindustrial population dynamics: demography, economy, and well-being in a Malthusian system. Current Anthropology, 39, 99–135.

    Article  Google Scholar 

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Acknowledgments

The authors wish to acknowledge financial support from the National Science Foundation (grant BCS-1113991). We would also like to thank four anonymous reviewers for their insightful comments on earlier versions of this manuscript. Their efforts have significantly improved the manuscript.

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Correspondence to Jacob Freeman.

Appendix: XPPAUT code

Appendix: XPPAUT code

The following code is designed to be run as an .ode file (e.g., HG.ode). The file can be run using the program XPPAUT, available for download at http://www.math.pitt.edu/bard/xpp/xpp.html. Lines marked by the pound sign (#) are comment lines that describe the functions that follow.

  • #simple model of hunter-gatherer land use intensification

  • #parameters

    par k = 1, r = 0.3, l = 1, p = 0.1, ga = 0.05, c = 0.02

    par q = 0.2, m = 0.7, al2 = 0.1, al1 = 4, be = 3, ead = 5, eads = 0.01

  • #hidden functions

  • #total harvest

    H(x,e)=p*q*e*x

  • #per capita harvest per unit effort and cost

    hpue=al*q*x

  • #resource flow deficit

    d=ga-hpue*e

  • #foraging interference

    al=l*(exp(-m*p))

  • #effort dynamics

  • #effort response to uptake levels

    edot(h,d,c)= (al1*d*h**be - al2*c**be)/(c**be + h**be)

  • #strength of response

    e_resp = ead*e/(eads+e)

  • x'=r*x*(1-x/k)-H(x,e)

    e'= e_resp*edot(hpue,d,c)

  • #aux cap = C

    aux den=p

    aux def=d

  • @ total=200,xlo=0,xhi=1.5,ylo=0,yhi=2,xp=x,yp=e,maxstor=30000,nmesh=200

  • @meth=qualrk,dt=0.01,but=mice:ii

    done

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Freeman, J., Anderies, J.M. Intensification, Tipping Points, and Social Change in a Coupled Forager-Resource System. Hum Nat 23, 419–446 (2012). https://doi.org/10.1007/s12110-012-9154-8

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  • DOI: https://doi.org/10.1007/s12110-012-9154-8

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