Julio Betancourt

Professional Preparation

• 1975
  B.A., University of Texas, Austin
  Major: Anthropology
  Minor: Geography
• 1983
  M.S., University of Arizona, Tucson
  Major: Geosciences
  Minor: Ecology & Evolutionary Biology
• 1989
  Ph.D., University of Arizona, Tucson
  Major: Geosciences
  Minor: Ecology & Evolutionary Biology

Brief Biography

I was born in Havana, Cuba and emigrated with my immediate family to the U.S. in 1961, at the age of 10. I attended primary and secondary parochial schools in Dallas, Texas and spent my undergraduate years at the University of Texas in Austin, Texas. I spent my senior year in Peru, taking a few classes in Lima and doing anthropological research, including an archeological dig on the coast, a history of an 18th century rebellion against Franciscans in eastern Peru, and an evaluation of contemporary missionary impact in the Peruvian 'selva.' That year, I developed the notion that most things in life were within my reach.

After graduating, I kicked around archeology for a few years, mostly Belize and the southwestern U.S., but eventually got serious and enrolled in a Ph.D. program at the University of New Mexico. I bailed out in the first semester after realizing that I was more interested in natural history than anthropology. The next step was pure serendipity.

That first semester in Albuquerque, I spent most weekends visiting a close friend and fellow archeologist, Mark Wimberly, at his ranch in Tularosa on the western escarpment of the Sacramento Mountains overlooking White Sands. One weekend, Mark asked me help him write a proposal to New Mexico State Parks. The gist of the proposal was to get Tom Van Devender, then at the University of Arizona and now at the Arizona-Sonora Desert Museum, to develop a vegetation history in the Sacramento Mountains using packrat middens. Tom liked the proposal, as did State Parks, and upon learning of my changing interests, he invited me to transfer to the Department of Geosciences at the University of Arizona. If I wanted, he said, I could occupy a desk at the Desert Laboratory on Tumamoc Hill, a 400-ha ecological reserve and long-term ecological research facility on Tucson's westside. Before leaving Albuquerque, I managed to swindle Jim Judge of the National Park Service for enough funds to do another packrat midden study at Chaco Canyon. A month later, I jammed my VW bug with all my worldly possessions and headed for Tucson.

Twenty-three years later finds me still occupying desk space at the Desert Laboratory, where I serve as Project Chief, National Research Program, Water Resources Division, U.S. Geological Survey and adjunct professor in the Departments of Geoscience and Geography at the University of Arizona. My research statement and bibliography fill in the rest of the story.

My wife, Teresa, and I have one son (Mark) and two daughters (Acacia and Francesca), all wonderful reminders that in life you can't hug your reprints.

Research Statement

The main objective of my research is to study ecosystem and watershed responses to climate variability on different temporal and spatial scales. More often than not, these responses can only be studied and understood in retrospect and at regional to subcontinental scales. Hence, much of my research is observational and relies on historical evidence; ultimate success depends on developing and contributing to networks of sites and data that can be synthesized at regional scales, and in some cases, globally. Retrospective studies call for development, refinement and calibration of new methods and approaches. History presents opportunities for natural experiments of important phenomena, for example how ENSO modulates the pulse of fires and floods across the regional landscape, how natural vegetation responds to CO₂ enrichment over the long term, and what are the ecological, hydrological and socioeconomic consequences of wildfires, plant invasions and regional droughts.

Historical studies may be the only way we can discriminate between natural and cultural causes of change, which is one of the great challenges facing environmental science in the 21st Century. It is neither possible nor wise to assess man's role in arroyo cutting, changing flood and fire frequency, shrub and tree encroachment of grasslands, and ultimately, global change, without historical context. Likewise, historical perspective is essential for gauging nature's impact on society- what is the historical range of natural variability for phenomena (e.g., drought) that affect risks from hazards and the relative success of resource and ecosystem management? In two decades worth of activities, I have addressed, to some degree, all of these issues.

My close colleagues, students and I have contributed to networks of rodent midden and tree-ring data in the Americas. We have designed, tested and/or applied a wide variety of approaches, including historical documents and photographs, instrumental hydrological and climatic data, long-term vegetation plots, tree rings, stable isotopes, ancient DNA, biometrical measurements, alluvial stratigraphy, and even ice cores to reconstruct the past. We have always made a point of applying this historical knowledge not only to fundamental questions of science, but also to contemporary issues facing management of water and other resources.

Examples of research from past Journal Covers.

Download an interview with Julio Betancourt from Earth and Sky Radio (mp3 format, 1.5 MB).

Publications

McCabe, G.J., Betancourt, J.L., Gray, S.T., Palecky, M. A., Hidalgo, H.G., in press, Associations of multi-decadal sea-surface temperature variability with U.S. drought: Quaternary International.

Quade, J., Rech, J., Betancourt, J., Latorre, C., Quade, B., Rylander, K.A., Fisher, T., 2008. Paleowetlands and regional climate change in the central Atacama Desert, northern Chile. Quaternary Research, 343-360.

Milly, P.C.D., Betancourt, J.L., Falkenmark, M., Hirsch, R.H., Kindzewicz, Z., Lettenmaier, D.P., Stouffer, R.J., In 2008, Stationary is Dead: Whither Water Management: Rethinking approaches to planning and design in a changing climate. Science 319, 573-574.

Holmgren, C.A., Rosello, E., Latorre, C., and Betancourt, J.L. 2008. Late-Holocene fossil rodent middens from the Arica region of northernmost Chile. Journal of Arid Environments 72, 677-686.

Hereford, R. and Betancourt, J.L. 2007. Historic geomorphology of the San Pedro River: archival and physical evidence. In: Stromberg, J. and Tellman, B., Ed., Ecology and Conservation of Desert Riparian Ecosystems: The San Pedro River Example. University of Arizona Press, Tucson (In Press)

Quade, J., Rech, J., Latorre, C., Betancourt, J., Gleason, E., Kalin-Arroyo, M., 2007, Soils at the hyperarid margin: the isotopic composition of soil carbonate from the Atacama Desert. Geochimica et Cosmochima Acta 71(15), 3772-3795.

Gray, S.T., Graumlich, L. J., and Betancourt, J.L. 2007. Annual precipitation in the Yellowstone National Park region since AD 1173. Quaternary Research, v. 68, p. 18-27

Betancourt, J. L., M. D. Schwartz, D. D. Breshears, C. A. Brewer, G. Frazer, J. E. Gross, S. J. Mazer, B. C. Reed, and B. E. Wilson, 2007. Evolving plans for the USA National Phenology Network. Eos Trans. AGU, 88 (19), 211.

McCabe, G., Betancourt, J.L., Hidalgo, H.G. 2007. Associations of decadal to multidecadal sea-surface temperature variability with Upper Colorado River flow. Journal of the American Water Resources Association 43, 183-192.

Holmgren, C., Norris, J., Betancourt, J. L. 2007. Inferences about winter temperatures and summer rains from the late Quaternary record of C4 perennial grasses and C3 desert shrubs in the northern Chihuahuan Desert. Journal of Quaternary Science 22, 141-161.

Parks, J. A., Dean, J. S., and Betancourt, J. L. 2006. Tree rings, drought and the Pueblo Abandoment of south-central New Mexico in the 1670s. D. E. Doyel and J. S. Dean, Eds., Environmental Change and Human Adaptation in the Ancient Southwest, University of Utah Press, p. 214-227.

Drees, K.P., Neilson, J.W., Betancourt, J.L., Quade, J., Henderson, D.A., Pryor, B., and Maier, R.M. 2006. Bacterial community structure of soils in a hyperarid region of the Atacama Desert. Applied and Environmental Microbiology 72, 7902-7908.

Smith, F.A. and Betancourt, J.L. 2006. Predicting woodrat (Neotoma) responses to anthropogenic warming from studies of the paleomidden record. Journal of Biogeography v. 33, p. 2061-2076

Holmgren, C., Betancourt, J.L., and Rylander, K.A. 2006. A 36,000-yr history of the Peloncillo Mountains, southeastern Arizona, USA. Palaeogeography, Palaeoclimatology, Palaeoecology 240, 405-422.

Gray, S.T., Betancourt, J.L., Jackson, S.T., Eddy, R. 2006. Role of multidecadal climate variability in a range extension of pinyon pine. Ecology 87, 1124-1130.

Latorre, C., Betancourt, J.L., and Arroyo, M.T.K. 2006. Vegetation and climate history of a perennial river canyon in the Rio Salado Basin (22 °S) of northern Chile. Quaternary Research 65, 450-466.

Keeley, J.E., Allen, C.D., Betancourt, J.L., Chong, G.W., Fotheringham, C.J. and Safford, H.D. 2006. A 21st Century Perspective on Postfire Seeding. Journal of Forestry March 2006, pp. 103-104.

Norris, J.T., Jackson, S.T., and Betancourt, J.L. 2006. Classification tree and minimum-volume ellipsoid analyses of the distribution of ponderosa pine in the western USA. Journal of Biogeography Vol. 33, pp. 342-360.

Betancourt, J.L., Schwartz, M.D., Breshears, D.D., Cayan, D.R., Dettinger, M.D., Inouye, D.W., Post, E., and Reed, B.C. 2005. Implementing a U.S.A.-national phenology network. Eos Transactions American Geophysical Union, Vol. 86, p. 539.

Maldonado, A., Betancourt, J. L., Latorre, C. and Villagran, C. 2005. Pollen analyses from a 50,000-yr rodent midden series in the southern Atacama Desert (25°30'S). Journal of Quaternary Science, Vol. 20, pp. 493-507.

Latorre, C., Betancourt, J. L., Rech, J. A., Quade, J., Holmgren, C., Placzek, C., Maldonado, A., Vuille, M., and Rylander, K. A. 2005. Late Quaternary History of the Atacama Desert. In "23 Degrees South: The Archaeology and Environmental History of the Southern Deserts". (M. Smith and P. Hesse, Eds.), National Museum of Australia Press, Canberra, Australia, pp. 73-90.

Reynolds, A. C., Betancourt, J. L., Quade, J., Patchett, P. J., Dean, J. S., and Stein, J. 2005. 87Sr/86Sr sourcing of ponderosa pine used in Anasazi Great House construction at Chaco Canyon, New Mexico. Journal of Archaeological Science 32, 1061-1075.

Jackson, S. T., Betancourt, J. L., Lyford, M. E., Gray, S. E., and Rylander, K. A. 2005. A 40,000-year woodrat-midden record of vegetational and biogeographic dynamics in northeastern Utah. Journal of Biogeography 32, 1085-1106.

Betancourt, J. L. 2004. Arid lands paleobiogeography: The fossil rodent midden record in the Americas. In Lomolino, M. V. and Heaney, L. R., Eds., Frontiers in Biogeography: New Directions in the Geography of Nature. Sinauer Associates Inc, p. 27-46.

Maier, R. M., Drees, K. P., Neilson, J. W., Henderson, D. A., Quade, J. and Betancourt, J.L. 2004. Microbial Life in the Atacama Desert. Science 306: 1280.

Gray, S. T., Fastie, C., Jackson, S. T., and Betancourt, J. L. 2004. Tree-ring based reconstruction of precipitation in the Bighorn Basin, Wyoming since A.D. 1260. Journal of Climate 17, 3855-3856.

Gray, S. T., Jackson, S. T., and Betancourt, J. L. 2004. Tree-ring based reconstructions of interannual to decadal-scale precipitation variability for northeastern Utah since 1226 A.D. Journal of the American Water Resources Association v. 40, p. 947-960.

Barclay, A.D., Betancourt, J.L., and Allen, C.D., 2004. Effects of seeding with ryegrass (Lolium multiflorum) on vegetation recovery following fire in a ponderosa pine (Pinus ponderosa) forest. International Journal of Wildland Fire v. 3, p. 183-194.

Gray, S.T., Graumlich, L.J., Betancourt, J.L. and Pederson, G.T. 2004. A tree-ring based reconstruction of the Atlantic Multidecadal Oscillation since 1567 A.D. Geophysical Research Letters 31, L12205, doi:10.1029/2004GL019932.

McCabe, G. J., Palecki, M. A., and Betancourt, J. L. 2004. Pacific and Atlantic Ocean influences on multidecadal drought frequency in the United States. Proceedings of the National Academy of Sciences 101, p. 4136-4141.

Milne, B. T., Moore, D. I., Betancourt, J. L., Parks, J. A., Swetnam, T. W., Parmenter, R. R., and Pockman, W. T. 2003. Multidecadal drought cycles in south-central New Mexico: Patterns and Consequences. In Climate Variability and Ecosystem Response at Long-Term Ecological Research (LTER) Sites, D. Greenland, D. G. Goodin and R. C. Smith, Eds. Oxford University Press, p. 286-307.

Holmgren, C., Peñalba, M. C., Rylander, K. A., and Betancourt, J. L. 2003. A 16,000 ¹⁴C yr BP packrat midden series from the U.S.A.-Mexico Borderlands. Quaternary Research v. 60, p. 319-329.

Lyford, M.E., Jackson, S.T., Betancourt, J.L. and Gray, S. 2003, Influence of landscape structure and climate variability on a late Holocene plant migration. Ecological Monographs v. 73, p. 567-583.

Gray, S. T., Betancourt, J. L., Fastie, C. L., Jackson, S. T. 2003. Patterns and sources of multidecadal oscillations in drought-sensitive tree-ring records from the central and southern Rocky Mountains. Geophysical Research Letters, v. 30, no. 6, p. 49-1 - 49-4, doi:10.1029/2002GL016154.

Betancourt, J. L. 2003. Review of Force, E.R., Vivian, R.G., Windes, T.C. and Dean, J.S. 2002. Relation of "Bonito" paleo-channels and base-level variations to Anasazi occupation, Chaco Canyon, New Mexico. Tucson: Arizona State Museum Archaeological Series 194 Progress in Physical Geography 27, 308-309.

Betancourt, J.L., Grissino-Mayer, H.D., Saltzer, M.W., and Swetnam, T.W., 2003, Reply to Baker and Genty's comments on "A test of annual resolution in stalagmite using tree rings". Quaternary Research 59, 479.

Latorre, C., Betancourt, J. L., Rylander, K. A., Quade, J. and Matthei, O., 2003, A 13.5-kyr vegetation history from the arid prepuna of northern Chile (22-23°S), Palaeogeography, Palaeoclimatology, Palaeoecology, 194, 223-246.

Rech, J. A., Pigati, J. S., Quade, J., and Betancourt, J. L., 2003, Re-evaluation of mid-Holocene wetland deposits at Quebrada Puripica, northern Chile, Palaeogeography, Palaeoclimatology, Palaeoecology, 194, 207-222.

Hofreiter, M., Betancourt, J.L., Sbriller, A.P., Markgraf, V. and McDonald, H.G. 2003. Phylogeny, diet and habitat of an extinct ground sloth from Cuchillo Curá, Neuquén Province, southwest Argentina. Quaternary Research 59, 364-378.

Smith, F. A. and Betancourt, J.L. 2003. The effect of Holocene temperature fluctuations on the evolution and ecology of Neotoma (woodrats) in Idaho and northwestern Utah. Quaternary Research 59, 160-171.

Jackson, S. T., Lyford, M. E., Betancourt, J.L. 2002. A 4000-year record of woodland vegetation from Wind River Canyon, central Wyoming. Western North American Naturalist 62, 405-413.

Terwilliger, V.J., Betancourt, J.L., Leavitt, S.W., and Van de Water, P.K. 2002, Leaf cellulose δD and δ¹⁸O trends with elevation and climate in semi-arid species. Geochimica et Coscomochima Acta 66, 3887-3900.

Betancourt, J.L. and Saavedra, B., 2002, Nuevo método paleoecológico para el estudio de zonas áridas en Sudamérica: paleomadrigueras de roedores (New paleoecological method for Quaternary studies in arid lands of South America: Rodent middens). Revista Chilena de Historia Natural 75, 527-546.

Betancourt, J.L., Grissino-Mayer, Salzer, M.W., and Swetnam, T.W., 2002, A test of 'annual resolution' in stalagmites using tree rings. Quaternary Research 58, 197-199.

Lyford, M. E., Betancourt, J. L. and Jackson, S. T. 2002. Holocene vegetation and climate history of the northern Bighorn Basin, southern Montana, U.S.A. Quaternary Research 58, 171-181.

Pearson, S. and Betancourt, J.L. 2002. Understanding arid environments using fossil rodent middens. Journal of Arid Environments v. 50, 499-511.

Rech, J. A., Quade, J. and Betancourt, J. L., 2002, Late Quaternary paleohydrology of the central Atacama Desert (22-24°S), Chile. Geological Society of America Bulletin v. 114, p. 334-348.

Latorre, C.L., Betancourt, J. L., Rylander, K. A., and Quade, J. A., 2002, Vegetation invasions into Absolute Desert: a 45,000-year rodent midden record from the Calama-Salar de Atacama Basins, Chile. Geological Society of America Bulletin v. 114, p. 349-366.

Betancourt, J.L., 2002, Book Review: Interhemispheric Climatic Linkages, Edited by Vera Markgraf. Arctic & Alpine Research v. 34, p. 226-227.

Van de Water, P.D., Leavitt, S.W., and Betancourt, J.L., 2002, Leaf cellulose δ¹³C variability with elevation, slope aspect and precipitation in the U.S. Southwest. Oecologia 132, 332-343

Kuch, M. Rohland, N., Betancourt, J.L., Latorre, C., Steppan, S., and Poinar, H. N. 2002, Molecular analysis of an 11,700-year old rodent midden from the Atacama Desert, Chile. Molecular Ecology, 11, 913-924.

Pedicino, L., Leavitt, S. W., Betancourt, J. L. 2002, Historical variations in δ¹³C_leaf of herbarium specimens in the southwestern U.S. Western North American Naturalist v. 62, p. 348-359.

Hunter, K. L., Betancourt, J. L., Riddle, B. R., Van Devender, T. R., Cole, K. L., and Spaulding, W. G. 2001. Ploidy race distributions since the Last Glacial Maximum in the North American desert shrub, Larrea tridentata. Global Ecology and Biogeography 10, 521-533.

English, N.E., Betancourt, J.L., Dean, J.S., Quade, J. 2001. Strontium isotopes reveal source of architectural timber at Chaco Canyon, New Mexico. Proceedings of the National Academy of Sciences 98, 11891-11896.

Placzek, C., Quade, J. and Betancourt, J. L., 2001, Holocene lake level fluctuations of Lago Aricota, southern Peru. Quaternary Research 56, 181-190.

Holmgren, C., Betancourt, J.L., Rylander, K.A., Roque, J., Tovar, O., Zeballos, H., Linares, E., and Quade, J., 2001, Holocene vegetation history from fossil rodent middens near Arequipa Peru. Quaternary Research. 56, 242-251.

Quade, J., Rech, J., Betancourt, J.L. and Latorre, C. 2001. Mid-Holocene climate in the south-central Andes: Humid or Dry? Science 292, 2391a.

Betancourt, J. L., Rylander, K. A., Peñalba, C., and McVickar, J. L. 2001. Late Quaternary vegetation history of Rough Canyon, south-central New Mexico, USA. Palaeogeography, Palaeoclimatology, and Palaeoecology, 165, 71-95.

Brown, T. J. and Betancourt, J. L. 2000. Effect of climate variability and forecasting on fuel treatment schedules in the western U.S. Proceedings of the USDA and DOI Fire Sciences Workshop.

Betancourt, J.L. 2000. Book Review: A Natural History of the Sonoran Desert, edited by Steven J. Phillips and Patricia Wentworth Cornus, University of California Press, 1999. Geotimes v., p. 34.

Anderson, R.S., J.L. Betancourt, J.I. Mead, R.H.Hevly and D.P. Adam. 2000. Middle- and late-Wisconsin paleobotanic and paleoclimatic records from the southern Colorado Plateau, USA. Palaeogeography, Palaeoclimatology, Palaeoecology 155: 31-57.

Betancourt, J. L. 2000. The Amazon reveals its secrets: at least partly. Science 290, 2274-2275.

Betancourt, J.L., Latorre, C., Rech, J. A., Quade, J., and Rylander, K. A., 2000, A 22,000-yr record of monsoonal precipitation from northern Chile's Atacama Desert. Science 289: 1542-1546.

Pendall, E., Betancourt, J. L. and Leavitt. 1999. Paleoclimatic significance of d D and d 13C in pinyon pine needles from packrat middens spanning the last 40,000 years. Palaeogeography, Palaeoclimatology and Palaeoecology 147: 53-72.

Swetnam, T.W., C.D. Allen, and J.L. Betancourt, 1999. Applied historical ecology: Using the past to manage for the future. Ecological Applications 64: 1189-1206.

White, P. S., J. Harrod, W. Romme, and J. Betancourt 1999. The role of disturbance and temporal dynamics. In: Ecological Stewardship: A common reference for ecosystem management (Johnson, N.C., A. J. Malk, W. T. Sexton, and R.Szaro, eds.). Oxford, England: Elsevier Science Ltd., p. 281-312.

Connin, S. L., Betancourt, J. L. and Quade, J. 1998. Late Pleistocene C4 plant dominance and summer rainfall in the southwestern U.S.A. from isotopic study of herbivore teeth. Quaternary Research 2: 170-193.

Smith, F. A. and Betancourt, J.L. 1998. Response of bushy-tailed woodrats (Neotoma cinerea) to late Quaternary climate change in the Colorado Plateau. Quaternary Research 50: 1-11.

Swetnam, T.W. and Betancourt, J.L. 1998. Mesoscale disturbance and ecological response to decadal-scale climate variability in the American Southwest. Journal of Climate 11: 3128-3147.

Allen, C.D., J.L. Betancourt, and T.W. Swetnam. 1998. Landscape Changes in the Southwestern United States: Techniques, Long-Term Datasets, and Trends. In T. Sisk, Ed., Land Use History of North America: Providing a Context for Understanding our Changing Environment. USGS Biological Science Report, USGS/BRD/BSR-1998-0003: 71-84.

Betancourt, J. L. 1998. Book Review: The Call of Distant Mammoths- Why the Ice Age Mammals Disappeared, by Peter Ward, Springer-Verlag, 1997. Palaeogeography, Palaeoclimatology and Palaeoecology v. 141, p. 163-175.

Betancourt, J. L. 1998. Book Review: Biomass Burning and Global Change, Volumes I and II, edited by Joel S. Levine, The MIT Press, 1997. Bulletin of the American Meteorological Society v. 79l, p.

Hereford, R. and Betancourt, J.L., 1997, Historic geomorphology of the San Pedro River: Archival and physical evidence. In Haynes, C.V. and Huckell, B., Clovis Hunters in the San Pedro Valley, Arizona, 9000 B.C.: Tucson: University of Arizona Press.

Markgraf, V., Betancourt, J.L., and Aasen Rylander, K. 1997. Late Holocene rodent middens from Rio Limay, Neuquen Province, Argentina: The Holocene 7: 325-329.

Shanley, J.B, Kendall, C., Pendall, E., Stevens, L.R., Michel, R.L., Phillips, P.J., Forester, R.M., Naftz, D.L., Liu, B., Stern, L., Wolfe, B.B., Chamberlain, C. P., Leavitt, S.W., Heaton, T.H.E., Mayer, B., Cecil, L.D., Lyons, W.B., Katz, B.G., Betancourt, J., McKnight, D.M., Blum, J.D., Edwards, T.W.D., House, H.R., Ito, E., Aravena, R., and Whelan, J.F., 1997. Isotopes as Indicators of Environmental Change. In: Kendall, C. and McDonnell, J.J., editors, Isotopes in Catchment Hydrology, chapter 23, Elsevier.

Dickfoss, P., Betancourt, J.L.. and Thompson, L. 1997. History and paleoclimatic potential of Candelaria Ice Cave, west-central New Mexico. In: Zidek, G., Ed., A Natural History of El Malpais: New Mexico Bureau of Mines & Mineral Resources, Bulletin 156t, p. 91-112. .

Betancourt, J.L. 1996. Long and short-term climatic influences on southwestern shrublands. In: Barrow, Jerry R.; MacArthur, E. Durant; Sosebee, Ronald E.; Tausch, R.J., comps. 1996. Proceedings: symposium on shrubland ecosystem dynamics in a changing climate; 1995 May 23-25; Las Cruces, NM. Gen. Tech. Rep. INT-GTR-338. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station, p. 5-9.

Gottfried, G.J., Swetnam, T.W., Allen, C.D., Betancourt, J.L., Chung-MacCoubrey, A. 1996. Pinyon-juniper woodlands. In: Finch, D. M. and Tainter, J. A., Ecology, Diversity and Sustainability of the Middle Rio Grande Basin. USDA Forest Service General Technical Report RM-GTR-278, p. 95-132.

Burgess, T.L., Betancourt, J.L., and Busby, J. 1995. Sampling bias in geographic patterns of plant species richness in the Sonoran Desert, U.S.A and Mexico, and Northern Territory, Australia. Proceedings of the Sky Island Conference, September 1994, Tucson, AZ, USDA, Forest Service General Technical Report RM-GTR-264, p. 84-90.

Betancourt, J.L., Craig, R., Burgess, T.L., Pierson, E.A., Shiozawa, L. 1995. A climate-plant distribution model for the Sonoran Desert- Annual Progress Report 1994. National Biological Service, Global Change Research Program, Sonoran Desert, p. 1-25.

Smith, F.A., Betancourt, J.L. and Brown, J.H., 1995. Effects of global warming on woodrat (Neotoma cinerea) body size during the last deglaciation. Science 270: 2012-2014.

Van de Water, P.D., Leavitt, S.L., and Betancourt, J.L. 1994, Trends in stomatal density and ¹³C/¹²C ratios of Pinus flexilis needles during last glacial/interglacial cycle. Science v. 264, p. 239-243.

Betancourt, J.L., Pierson, E.A., Aasen Rylander, K., Fairchild-Parks, J.A., and Dean, J.S. 1993. Influence of history and climate on New Mexico piñon-juniper woodlands. In: Aldon, E.F. and Shaw, D.W., (Eds.), Managing Piñon-Juniper Ecosystems for Sustainability and Social Needs: Proceedings of the Symposium April 26-30, Santa Fe, New Mexico. Gen. Tech. Rep. RM-236, Fort Collins, CO: USDA Forest Service, Rocky Mountain & Range Experiment Station, p. 42-62.

Webb, R.H. and Betancourt, J.L., 1992, Climatic variability and flood frequency of the Santa Cruz River, Pima County, Arizona: U.S. Geological Survey Water-Supply Paper 2379.

Betancourt, J. L. and Tharp, V. L., eds., 1992. Proceedings of the Eight Annual Pacific Climate (PACLIM) Workshop, Asilomar, California, April, 1990: California Department of Water Resources, Interagency Ecological Studies Program, Technical Report 26, 257 p.

Swetnam, T.W. and Betancourt, J.L., 1992, Temporal patterns of ENSO-wildfire teleconnections in the southwestern United States. In Diaz, H. F. and Markgraf, V., El Niño: Historical and paleoclimatic aspects of the Southern Oscillation. Cambridge University Press, 259-270.

Lowenstein, J. M., Rainey, W.N., and Betancourt, J. L., 1991, Immunospecific albumin in fossil packrat, porcupine and hyrax urine: Naturwissenschaften, V. 78, P. 26-27.

Betancourt, J.L., Schuster, W.S., Mitton, J.B., and Anderson, R.S., 1991, Fossil and genetic history of a pinyon pine (Pinus edulis) isolate: Ecology v. 72, p. 1685-1697.

Betancourt, J.L., Van Devender, T.R., and Martin, P.S., 1990, Packrat middens: The last 40,000 years of biotic change: Tucson, Arizona, University of Arizona Press, 472 p.

Betancourt, J.L., Van Devender, T.R., and Martin, P.S., 1990, Introduction, in Betancourt, J.L., Van Devender, T.R., and Martin, P.S., (eds), Packrat middens: The last 40,000 years of biotic change: Tucson, Arizona, University of Arizona Press, p. 2-11.

Spaulding, W.G., Betancourt, J.L., Cole, K.L., and Croft, L., 1990, Packrat middens, their composition and methods of analysis, in Betancourt, J.L., Van Devender, T.R., and Martin, P.S., (eds), Packrat middens: The last 40,000 years of biotic change: Tucson, Arizona, University of Arizona Press, p. 59-84.

Webb, R.H., and Betancourt, J.L., 1990, The spatial distribution of radiocarbon ages from packrat middens, in Betancourt, J.L., Van Devender, T.R., and Martin, P.S., (eds), Packrat middens: The last 40,000 years of biotic change: Tucson, Arizona, University of Arizona Press, p. 85-102.

Betancourt, J.L., 1990, Late Quaternary biogeography of the Colorado Plateau, in Betancourt, J.L.., Van Devender, T.R., and Martin, P.S., (eds), Packrat middens: The last 40,000 years of biotic change: Tucson, Arizona, University of Arizona Press, p. 259-292.

Long, A., Warnecke, L., Betancourt, J.L., and Thompson, R.S., 1990, Deuterium variations in plant cellulose from packrat middens, in Betancourt, J.L., Van Devender, T.R., and Martin, P.S., (eds), Packrat middens: The last 40,000 years of biotic change: Tucson, Arizona, University of Arizona Press, p. 381-396.

Betancourt, J.L., Van Devender, T.R., and Martin, P.S., 1990, Synthesis and prospectus, in Betancourt, J.L., Van Devender, T.R., and Martin, P.S. (eds), Packrat middens: The last 40,000 years of biotic change: Tucson, Arizona, University of Arizona Press, p. 435-447.

Betancourt, J.L. and MacKay, A.M., eds., 1990, Proceedings of the Sixth Annual Pacific Climate (PACLIM) Workshop, Asilomar, California, March 5-8, 1989: California Department of Water Resources, Interagency Ecological Studies Program, Technical Report 23.

Betancourt, J.L., 1990, Introduction. in Betancourt, J. L. and MacKay, A.M., (eds), Proceedings of the Sixth Annual Pacific Climate (PACLIM) Workshop, Asilomar, California, March 5-8, 1989, California Department of Water Resources, Interagency Ecological Studies Program, Technical Report 23, p. 1-4.

Webb, R.H., and Betancourt, J.L., 1990, Climatic effects on flood frequency: An example from southern Arizona, in Betancourt, J.L. and MacKay, A.M., (eds), Proceedings of the Sixth Annual Pacific Climate (PACLIM) Workshop, Asilomar, California, March 5-8, 1989: California Department of Water Resources, Interagency Ecological Studies Program, Technical Report 23, p. 61-66.

Swetnam, T.R., and Betancourt, J.L., 1990, El Niño-Southern Oscillation (ENSO) phenomena and forest fires in the southwestern United States, in Betancourt, J.L. and MacKay, A. M.,(eds), Proceedings of the Sixth Annual Pacific Climate (PACLIM) Workshop, Asilomar, California, March 5-8, 1989, California Department of Water Resources, Interagency Ecological Study Program, Technical Report 23, p. 129-135.

Swetnam, T.R. and Betancourt, J.L., 1990, Fire-Southern Oscillation relations in the southwestern United States: Science v. 24, p. 1017-1020.

Betancourt, J. L. and Turner, R.M., 1988, Historic arroyo-cutting and subsequent channel changes at the Congress Street crossing, Santa Cruz River, Tucson, Arizona, in Whitehead, E.E., Hutchinson, C.F., Timmermann, B.N., and Varady, R.G. (eds), Arid Lands Today and Tomorrow: Boulder, Colorado, Westview Press, p. 1353-1371.

Betancourt, J.L., 1987, Paleoecology of pinyon-juniper woodlands, summary: Reno, Nevada, Proceedings, Pinyon-juniper Conference, U.S.D.A. Forest Service, General Technical Report INT, v. 215, p. 129-139.

Van Devender, T.R., Thompson, R.S., and Betancourt, J.L., 1987, Vegetation and history of the Southwest, the nature and timing of the late Wisconsin-Holocene transition, in Ruddiman, W.F. and Wright, H.E., Jr. (eds), North America and adjacent oceans during the last deglaciation: Boulder, Colorado, Geological Society of America, The Geology of North America, v. K3, p. 323-352

Betancourt, J.L., Dean, J.A., Hull, Herbert, 1986, Prehistoric long-distance transport of construction beams, Chaco Canyon, New Mexico: American Antiquity, v. 51, p. 370-375.

Betancourt, J.L., Van Devender, T.R., and Rose, Martin, 1986, Comparison of plant macrofossils in woodrat (Neotoma) and porcupine (Erethizon dorsatum) middens in the western United States: Journal of Mammalogy, v. 67, p. 266-273.

Betancourt, J.L., and Biggar, Norma, 1985, Preliminary assessment of late Quaternary vegetation and climate of southeastern Utah based on analyses of packrat middens: Columbus, Ohio, Batelle Memorial Institute, Office of Nuclear Waste Isolation, Technical Report v. 570, 120 p.

Betancourt, J.L., and Davis, O.K., 1984, Fossil packrat middens from Canyon de Chelly, northeastern Arizona, paleoecological and archeological implications: Quaternary Research, v. 21, p. 556-564.

Betancourt, J.L., Long, Austin, Donahue, Douglas, Jull, A.J.T., and Zabel, Ted, 1984, Precolumbian age for North American Corispermum L. (Chenopodiaceae) confirmed by accelerator radiocarbon dating: Nature, v. 311, p. 653-655.

Betancourt, J.L., 1984, Late Quaternary plant zonation and climate in southeastern Utah: Great Basin Naturalist, v. 4, p. 1-35.

Van Devender, T.R., Betancourt, J.L., and Wimberly, Mark, 1984, Biogeographic implications of a packrat midden sequence from the Sacramento Mountains, south-central New Mexico: Quaternary Research, v. 22, p. 344-360.

Betancourt, J.L., Van Devender, T.R., and Martin, P.S., 1983, Fossil packrat middens from Chaco Canyon, New Mexico: Cultural and ecological significance: in Wells, S.G., Love, D.W., and Gardner, T.W. (eds), Chaco Canyon country, a field guide to the geomorphology, Quaternary geology, paleoecology, and environmental geology of northwestern New Mexico: Albuquerque, American Geomorphological Field Group, p. 207-217.

Samuels, Michael, and Betancourt, J.L., 1982, Modeling the long-term effects of fuelwood harvests on pinyon-juniper woodlands: Environmental Management v. 6, p. 505-515.

Betancourt, J.L., 1981, Reconnaissance of archeological resources in the southern Quitman Mountains, Hudspeth County, Texas: Austin, Texas Antiquities Committee Permit Series, v. 6, p. 83-114.

Betancourt, J.L., 1981, Reconnaissance of archeological resources in the southern Quitman Mountains, Hudspeth County, Texas: Austin, Texas Antiquities Committee Permit Series, v. 6, p. 27-82.

Betancourt, J.L., 1981, A history of Mescalero Apache-U.S. Army encounters in Dog Canyon, New Mexico, 1849-1880: Albuquerque,USDA-Forest Service, Cultural Resources on the Lincoln National Forest Miscellaneous Papers, v. 34, p. 50-66.

Betancourt, J.L., and Van Devender, T.R., 1981, Holocene vegetation in Chaco Canyon, New Mexico: Science, v. 214, p. 658-660.

Betancourt, J.L., 1980, Historical overview of the lower Rio Puerco and Rio Salado, central New Mexico: in Wimberly, M. and Eidenbach, P. (eds), Reconnaissance study of the archeological and related resources of the lower Puerco and Salado drainages: Albuquerque, U.S. Army Corps of Engineers, p. 23-58.

Wimberly, Mark, Eidenbach, P., and Betancourt, J.L., 1979, Canyon del Perro, a history of Dog Canyon, New Mexico: Santa Fe, New Mexico Parks and Recreation Commission, 261 p.

Betancourt, J.L., 1978, An archeological synthesis of the Tucson Basin, Focus on the Santa Cruz Riverpark: Tucson, Arizona State Museum Archeological Series, v. 125, 108p.

Betancourt, J.L., 1978, Cultural resources within the proposed Santa Cruz Archeological District: Tucson, Arizona State Museum Archeological Series, v. 125, 113 p.

Betancourt, J.L., 1977, Archeological survey of a proposed lignite mine area, the Shell-Rockdale Lease: Austin, Texas Historical Commission, Archeological Survey, v. 21, 117 p.