Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-07T15:25:51.085Z Has data issue: false hasContentIssue false

A Quantitative Model for Distinguishing Between Climate Change, Human Impact, and Their Synergistic Interaction as Drivers of the Late Quaternary Megafaunal Extinctions

Published online by Cambridge University Press:  21 July 2017

Charles R. Marshall
Affiliation:
Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, Berkeley, CA 94720 USA
Emily L. Lindsey
Affiliation:
Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, Berkeley, CA 94720 USA
Natalia A. Villavicencio
Affiliation:
Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, Berkeley, CA 94720 USA
Anthony D. Barnosky
Affiliation:
Department of Integrative Biology, Museum of Paleontology, and Museum of Vertebrate Zoology, University of California, Berkeley, Berkeley, CA 94720 USA
Get access

Abstract

A simple quantitative approach is presented for determining the relative importance of climate change and human impact in driving late Quaternary megafaunal extinctions. This method is designed to determine whether climate change or human impact alone can account for these extinctions, or whether both were important, acting independently (additively) and/or synergistically (multiplicatively). This approach is applied to the megafaunal extinction in the Última Esperanza region of southern Chile. In this region, there is a complex pattern of extinction. Records of environmental change include temperature proxies and pollen records that capture the transition from cold grasslands to warmer, moister forests, as well as evidence of initial human arrival. Uncertainty in extinction times and time of human arrival complicates the analysis, as does uncertainty about the size of local human populations, and the nature, strength, and persistence of their impacts through the late Pleistocene and early Holocene. Results of the Ultima Esperanza analysis were equivocal, with evidence for climate- and human-driven extinction, with each operating alone or additively. The results depend on the exact timing of extinctions and human arrival, and assumptions about the kinds of pressures humans put on the megafauna. There was little evidence for positive synergistic effects, while the unexpected possibility of negative synergistic interactions arose in some scenarios. Application of this quantitative approach highlights the need for higher precision dating of the extinctions and human arrival, and provides a platform for sharpening our understanding of these megafaunal extinctions.

Type
Research Article
Copyright
Copyright © 2015 by The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alroy, J. 1999. Putting North America's end-Pleistocene megafaunal extinction in context: Large-scale analyses of spatial patterns, extinction rates, and size distributions, p. 105143 In MacPhee, R. D. E. (ed.), Extinctions in Near Time. Kluwer Academic/Plenum Publishers, New York.Google Scholar
Alroy, J. 2001. A multispecies overkill simulation of the end-Pleistocene megafaunal mass extinction. Science, 292:18931896.Google Scholar
Barnosky, A. D. 1985. Taphonomy and herd structure of the extinct Irish elk, Megaloceros giganteus . Science, 228:340344.CrossRefGoogle ScholarPubMed
Barnosky, A. D. 1986. “Big game” extinction caused by late Pleistocene climatic change: Irish elk (Megaloceros giganteus) in Ireland. Quaternary Research, 25:128135.Google Scholar
Barnosky, A. D. 2008. Megafauna biomass tradeoff as a driver of Quaternary and future extinctions. Proceedings of the National Academy of Sciences USA, 105(suppl. 1):1154311548.CrossRefGoogle ScholarPubMed
Barnosky, A. D., Koch, P. L., Feranec, R. S., Wing, S. L., and Shabel, A. B. 2004. Assessing the causes of late Pleistocene extinctions on the continents. Science, 306:7075.Google Scholar
Barnosky, A. D., and Lindsey, E. L. 2010. Timing of Quaternary megafaunal extinction in South America in relation to human arrival and climate change. Quaternary International, 217:1029.Google Scholar
Barnosky, A. D., Lindsey, E. L., Villavicencio, N. A., Bostelmann, E., Hadly, E. A., Wanket, J., and Marshall, C. R. 2015. The variable impact of Late Quaternary megafaunal extinction in causing ecological state shifts in North and South America. Proceedings of the USA National Academy of Sciences, in press.CrossRefGoogle Scholar
Bond, W. J. 2005. Large parts of the world are brown or black: A different view on the ‘Green World’ hypothesis. Journal of Vegetation Science, 16:261266.Google Scholar
Bond, W. J., and Keeley, J. E. 2005. Fire as a global ‘herbivore’: the ecology and evolution of flammable ecosystems. Trends in Ecology and Evolution, 20(7):337394.CrossRefGoogle ScholarPubMed
Bradshaw, C. J. A., Cooper, A., Turney, C. S. M., and Brook, B. W. 2012. Robust estimates of extinction time in the geological record. Quaternary Science Reviews, 33:1419.CrossRefGoogle Scholar
Brook, B. W., and Barnosky, A. D. 2012. Quaternary extinctions and their link to climate change, p. 179198 In Hannah, L. (ed.), Saving a Million Species. Island Press, Washington, D. C.Google Scholar
Brook, B. W., and Bowman, D. M. J. S. 2004. The uncertain blitzkrieg of Pleistocene megafauna. Journal of Biogeography, 31:517523.CrossRefGoogle Scholar
Dirzo, R., Young, H. S., Galetti, M., Ceballos, G., Isaac, N. J. B., and Collen, B. 2014. Defaunation in the Anthropocene. Science, 345:401406.CrossRefGoogle ScholarPubMed
Flannery, T. F., and Roberts, R. G. 1999. Late Quaternary extinctions in Australasia: an overview, p. 239255 In MacPhee, R. D. E. (ed.), Extinctions in Near Time: Causes, Contexts, and Consequences. Kluwer Academic/Plenum Publishers, New York.Google Scholar
Galetti, M., and Dirzo, R. 2013. Ecological and evolutionary consequences of living in a defaunated world. Biological Conservation, 163:16.CrossRefGoogle Scholar
Gill, J. L. 2014. Ecological impacts of the late Quaternary megaherbivore extinctions. New Phytologist, 201:11631169.CrossRefGoogle ScholarPubMed
Gill, J. L., Williams, J. W., Jackson, S. T., Donnelly, J. P., and Schellinger, G. C. 2012. Climatic and megaherbivory controls on late-glacial vegetation dynamics: a new, high-resolution, multi-proxy record from Silver Lake, Ohio. Quaternary Science Reviews, 34:6880.Google Scholar
Gill, J. L., Williams, J. W., Jackson, S. T., Lininger, K. B., and Robinson, G. S. 2009. Pleistocene megafaunal collapse, novel plant communities, and enhanced fire regimes in North America. Science, 326:11001103.Google Scholar
Goldberg, A., Mychajliw, A. M., Sztraicher, D., and Hadly, E. A. 2015. Evidence for the peopling of South America: archeological and genetic perspectives, 84th Annual Meeting of the American Association of Physical Anthropology. American Association of Physical Anthropology, St. Louis, Missouri.Google Scholar
Graham, R. W., and Lundelius, E. L. Jr. 1984. Coevolutionary disequilibrium and Pleistocene extinction, p. 223249 In Martin, P. S. and Klein, R. G. (eds.), Quaternary Extinctions: A Prehistoric Revolution. University of Arizona Press, Tucson.Google Scholar
Grayson, D. K. 1984. Archaeological associations with extinct Pleistocene mammals in North America. Journal of Archaeological Science, 11:213221.CrossRefGoogle Scholar
Grayson, D. K. 2001. Did human hunting cause mass extinction? Science, 294:1459.Google Scholar
Grayson, D. K., and Meltzer, D. J. 2003. A requiem for North American overkill. Journal of Archaeological Science, 30:585593.Google Scholar
Guilday, J. E. 1967. Differential extinction during late-Pleistocene and Recent times, p. 121140 In Martin, P. S. and Wright, H. E. Jr (eds.), Pleistocene Extinctions: The Search for a Cause. Yale University Press, New Haven.Google Scholar
Guilday, J. E. 1984. Pleistocene extinction and environmental change: case study of the Appalachians, p. 250258 In Martin, P. S. and Klein, R. G. (eds.), Quaternary Extinctions: A Prehistoric Revolution. University of Arizona Press, Tucson.Google Scholar
Guthrie, R. D. 2003. Rapid body size decline in Alaskan Pleistocene horses before extinction. Nature, 426:169171.CrossRefGoogle ScholarPubMed
Guthrie, R. D. 2006. New carbon dates link climatic change with human colonization and Pleistocene extinctions. Nature, 441:207209.Google Scholar
Koch, P. L., and Barnosky, A. D. 2006. Late Quaternary extinctions: State of the debate. Annual Review of Ecology Evolution and Systematics, 37:215250.CrossRefGoogle Scholar
MacPhee, R. D. E. 1999. Extinctions in Near Time: Causes, Contexts, and Consequences. Kluwer Academic/Plenum, New York.CrossRefGoogle Scholar
Marshall, C. R. 1990. Confidence intervals on stratigraphic ranges. Paleobiology, 16:110.Google Scholar
Marshall, C. R. 2010. Using confidence intervals to quantify the uncertainty in the end-points of stratigraphic ranges, p. 291316 In Alroy, J. and Hunt, G. (eds.), Quantitative Methods in Paleobiology, The Paleontological Society Papers 16, Yale Press, New Haven.Google Scholar
Martin, P. S. 1966. African and Pleistocene overkill. Nature, 212:339342.Google Scholar
Martin, P. S. 1967. Prehistoric overkill, p. 75120 In Martin, P. S. and Wright, H. E. Jr (eds.), Pleistocene Extinctions: The Search for a Cause. Yale University Press, New Haven.Google Scholar
Martin, P. S. 1973. The discovery of America. Science, 179:969974.Google Scholar
Martin, P. S. 1984. Prehistoric overkill: the global model, p. 354403 In Martin, P. S. and Klein, R. G. (eds.), Quaternary Extinctions: A Prehistoric Revolution. University of Arizona Press, Tucson.Google Scholar
Martin, P. S. 1990. 40,000 years of extinction on the “planet of doom”. Palaeogeography, Palaeoclimatology, Palaeoecology, 82:187201.Google Scholar
Martin, P. S., and Steadman, D. W. 1999. Prehistoric extinctions on islands and continents, p. 1755 In MacPhee, R. D. E. (ed.), Extinctions in Near Time: Causes, Contexts, and Consequences. Kluwer Academic/Plenum Publishers, New York.CrossRefGoogle Scholar
McInerny, G. J., Roberts, D. L., Davy, A. J., and Cribb, P. J. 2006. Significance of sighting rate in inferring extinction and threat. Conservation Biology, 20:562e567.Google Scholar
Mosimann, J. E., and Martin, P. S. 1975. Simulating overkill by Paleoindians. American Scientist, 63:304313.Google Scholar
Roberts, R. G., Flannery, T. F., Ayliffe, L. K., Yoshida, H., Olley, J. M., Prideaux, G. J., Laslett, G. M., Baynes, A., Smith, M. A., Jones, R., and Smith, B. L. 2001. New ages for the last Australian megafauna: Continent-wide extinction about 46,000 years ago. Science, 292:18881892.Google Scholar
Saltré, F. E., Brook, B. W., Rodríguez-Rey, M., Cooper, A., Johnson, C. N., Turney, C. S. M., and Bradshaw, C. J. A. 2015. Uncertainties in specimen dates constrain the choice of statistical method to infer extinction time. Quaternary Science Reviews, 112:128137.Google Scholar
Strauss, D., and Sadler, P. M. 1989. Classical confidence intervals and Bayesian probability estimates for ends of local taxon ranges. Mathematical Geology, 21:411427.Google Scholar
Stuart, A. J. 1999. Late Pleistocene megafaunal extinctions: a European perspective, p. 257270 In MacPhee, R. D. E. (ed.), Extinctions in Near Time: Causes, Contexts, and Consequences. Kluwer Academic/Plenum Publishers, New York.CrossRefGoogle Scholar
Stuart, A. J., Kosintsev, P. A., Higham, T. F. G., and Lister, A. M. 2004. Pleistocene to Holocene extinction dynamics in giant deer and woolly mammoth. Nature, 431:684690.Google Scholar
Stuart, A. J., Sulerzhitsky, L. D., Orlova, L. A., Kuzmin, Y. V., and Lister, A. M. 2002. The latest woolly mammoths (Mammuthus primigenius Blumenbach) in Europe and Asia: a review of the current evidence. Quaternary Science Reviews, 21(14–15): 15591569.CrossRefGoogle Scholar
Trueman, C. N. G., Field, J. H., Dortch, J., Charles, B., and Wroe, S. 2005. Prolonged coexistence of humans and megafauna in Pleistocene Australia. Proceedings of the USA National Academy of Sciences, 102:83818385.Google Scholar
Turvey, S. T. 2009. Holocene Extinctions. Oxford University Press, Oxford, 364 p.Google Scholar
Villavicencio, N. A., Lindsey, E. L., Martin, F. M., Borrero, L. A., Moreno, P. I., Marshall, C. R., and Barnosky, A. D. 2015. Combination of humans, climate, and vegetation change triggered Late Quaternary megafauna extinction in the Ultima Esperanza region, southern Patagonia, Chile. Ecography, 38:116.Google Scholar
Wroe, S., Field, J., and Grayson, D. K. 2006. Megafaunal extinction: climate, humans and assumptions. Trends in Ecology and Evolution, 21:6162.Google Scholar
Wroe, S., Field, J. H., Archera, M., Grayson, D. K., Price, G. J., Louys, Julien, Faith, J. T., Webb, G. E., Davidson, I., and Mooney, S. D. 2013. Climate change frames debate over the extinction of megafauna in Sahul (Pleistocene Australia–New Guinea). Proceedings of the USA National Academy of Sciences, 110(22):87778781.Google Scholar
Young, H. S., Dirzo, R., Helgen, K. M., McCauley, D. J., Billeter, S. A., Kosoy, M. Y., Osikowicz, L. M., Salkelde, D. J., Young, T. P., and Dittmarh, K. 2014. Declines in large wildlife increase landscape-level prevalence of rodent-borne disease in Africa. Proceedings of the USA National Academy of Sciences, 111(19):70367041.Google Scholar
Young, H. S., McCauley, D. J., Helgen, K. M., Goheen, J. R., Otárola-Castillo, E., Palmer, T. M., Pringle, R. M., Young, T. P., and Dirzo, R. 2013. Effects of mammalian herbivore declines on plant communities: observations and experiments in an African savanna. Journal of Ecology, 101:10301041.Google Scholar