Jonathan G. Wynn

Research Interests

Stable isotope geochemistry

Global carbon cycle, and the role of soil carbon

Paleoenvironments and paleoclimate

Paleoclimatic forcing of human evolution

Geological record of fossil soils

Profile

1995	B.S., with Honors, Geological Engineering, University of Utah.
1995	B.S., with Honors, Geology, University of Utah.
1998	M.S., Geology, University of Utah, Graduate Advisor: Thure E. Cerling.
2001	Ph.D., Geology, University of Oregon, Graduate Advisor: Gregory J. Retallack.
2001-03	Visiting Research Fellow, and NSF International Research Fellow, Research School of Earth Sciences, the Australian National University, Australia.
2003-04	Research Fellow and Courtesy Research Associate, Department of Geological Sciences, University of Oregon.
2004	Postdoctoral Researcher, Carbon Cycle Research Group, US Geological Survey.
2004-05	Research Fellow, School of Geography and Geosciences, University of St. Andrews.
2006	Assistant Professor, Department of Earth and Environmental Sciences, Lehigh University.
2006-pres.	Assistant Professor, Department of Geology, University of South Florida.

Recent and Ongoing Research Projects

Paleoenvironments of human evolution in the Dikika Research Area , collaborator with Zeresenay Alemseged, Denis Geraads, Denne Reed, Rene Bobe, Shannon McPherron, and others.

Oxygen isotopes in mammalian tooth enamel from the Ethiopian Rift as a paleoenvironmental proxy, PhD supervisor of project by Zelalem Kubsa Bedaso

Exploration of Neogene Rift Valley Paleoenvironmental Record from the Red Series sediments, northern Afar, Ethiopia

Monitoring soil hydrology and the soil carbon cycle along a soil moisture gradient in a Florida Flatwoods Ecosystem

A Keeling Plot approach to diffusive CO2 flux in C3- and C4-dominated soil profiles, MS supervisor of project by Jennifer Chelladurai

Paleoclimatic archives from Ice Deposits in Scarisoara Ice Cave, Apuseni Mountains, Romania, collaborator with Bogdan Onac on PhD project by Aurel Persoiu

Biotically-induced carbonic acid speleogenesis in caves: Thornton's Cave, Florida, Crescent Top Cave, and San Salvador, Bahamas, collaborator on PhD project by Dorien McGee

Sulfur isotopic constraints on the genesis of cave gypsum and sulfuric acid speleogenesis in caves of the Cerna Valley, Romania, collaborator with Bogdan Onac on MS Project by Jon Sumrall

Funded Research Grants

2010-13, co-PI with Michael Bird and others, Australian Research Council Discovery Program, "The Abundance and Isotopic Composition of Pyrogenic Carbon in Tropical Savannas

2009, PI, National Science Foundation Sedimentary Geology and Paleobiology, "Exploration of Late Miocene strata in a critical gap of the hominoid record: The Red Series of northern Afar, Ethiopia

2009, PI, National Geographic Society, "Exploration of Paleoenvironmental Potential of The Red Series of northern Afar, Ethiopia

2007-2009, PI, American Chemical Society Petroleum Research Fund, Type G Grant: Stable Isotopic Constraints on Carbon Exchange During Heterotrophic Decomposition of Soil Organic Matter

2007-2008, PI, USF Division of Sponsored Research, New Researcher Grant: The Role of Soil Hydrology in Determining Terrestrial Carbon Storage in the Green Swamp, central Florida.

2008-2010, co-PI with Bogdan Onac and others, USF Division of Sponsored Research, Interdisciplinary Research Development Grant: Ice Deposits in Caves: A Novel Paleoclimatic Archive.

Publications

2010. Wynn, J.G., Sumrall, J.B., and Onac, B.P. Sulfur isotopic composition and the source of dissolved sulfur species in thermo-mineral springs of the Cerna Valley, Romania, Chemical Geology, in press

2010. Bedaso, Z.K., Wynn, J.G., Geraads, D., and Alemseged, Z. Paleoenvironmental reconstruction of the Asbole fauna (Busidima Formation, Afar, Ethiopia) using stable isotopes, Geobios, in press

2010. Wynn, J.G., and Bedaso, Z.K. Is the Pliocene Ethiopian Monsoon Extinct? A comment on Aronson et al., (2008) J. hum. Evol., in press

2008. Quade, J. & Wynn, J.G., eds., The Geological Context of Human Evolution in the Horn of Africa. Geological Soceity of America Special Publication 446.

2008. Wynn, J.G., Roman, D.C., Alemseged, Z., Reed, D., Geraads, D., and Munros, S., Stratigraphy, depositional environments and basin structure of the Hadar and Busidima Formations at Dikika, Ethiopia, in: Quade, J. & Wynn, J.G., eds., The Geological Context of Human Evolution in the Horn of Africa. Geological Soceity of America Special Publication, p 87-118.

2008. Wynn, J.G., Bird, M.I., Environmental controls on the stable carbon isotopic composition of soil organic carbon: Implications for modelling the distribution of C3 and C4 plants, Australia, Tellus B., v.60, p.604-621.

2008. in press. Craven, K.F., Bird, M.I., Austin, W.E.N., Wynn, J.G., Isotopic variability in the intertidal acorn barnacle, Semibalanus balanoides: A novel sea-level proxy indicator. Journal of the Geological Society, London, v. 303, p. 173-185.

2007. Wynn, J.G., Bird, M.I., C4-derived soil organic carbon decomposes faster than its C3 counterpart, Global Change Biology. v.13, p.2206-2217

2007. Wynn, J.G. Carbon isotope fractionation during decomposition of organic matter in soils and paleosols: Implications for paleoecological interpretations of paleosol. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 251, p. 437-448.

2006. Wynn, J.G., Alemseged, Z., Bobe, R., Geraads, D., Reed, D., Roman, D.C. Geological and palaeontological context of a Pliocene juvenile hominin at Dikika, Ethiopia, Nature, v.443, p.332-336.

2006. Alemseged, Z., Kimbel, W., Spoor, F., Bobe, R., Geraads, D., Reed, D., Wynn, J.G. The earliest juvenile hominin skeleton from Dikika, Ethiopia, Nature, v. 443, p.296-301.

2006. Wynn, J.G., Bird, M.I., Vellen, L., Carter, J., and Berry, S.L. Measuring variation of the Australian soil organic carbon pool with climatic, edaphic and biotic controls, Glob. Biogeochem. Cycles. v.20, GB1007.

2006. Wynn, J.G., Harden, J.W., and Fries, T.L. Carbon isotope depth profiles and soil organic carbon dynamics in the Mississippi Basin. Geoderma. v.131, p.89-109.

2005. Krull, E.S., Skjemstad, J.O., Burrows, W.H. Bray, S.G., Wynn, J.G., Bol, R., Spouncer, L. and Harms, B. Tracing recent vegetation changes in Australia’s grazed woodlands by δ13C analyses of soil organic matter, Geoderma, v.126, p. 241-259.

2005. Wynn, J.G., Bird, M.I., Wong, V.N.L. Rayleigh distillation and the depth profile of 13C/12C ratios in soil organic carbon from two soils in Iron Range National Park, Far North Queensland, Australia, Geochim. Cosmochim. Acta. v.69, p.1961-1973.

2005. Alemseged, Z., Wynn, J.G.,, Geraads, D. & Reed, D. First hominin from the Basal Member of the Hadar Formation, Dikika, Ethiopia. J. hum. Evol., v.49, p.499-514.

2004. Wynn, J.G., Influence of Plio-Pleistocene Aridification on Human Evolution: Evidence from Paleosols of the Turkana Basin, Kenya, Am. J. Phys. Anthropol. v. 123, p.106-118.

2004. Retallack, G.J., Wynn, J.G. & Fremd, T. J. Glacial-interglacial-scale palaeoclimatic change without large ice sheets in the Oligocene of central Oregon, Geology v. 32, p. 297-300.

2004. Geraads, D., Alemseged, Z., Reed, D., Wynn, J.G. & Roman, D. The Pleistocene fauna from Asbole, lower Awash valley, Ethiopia. Géobios v. 37, p. 697-718.

2003. Wynn, J.G. Towards a physical model of CO2-induced stomatal frequency response. New Phytologist, v.157, p.394-398.

2002. Retallack, G.J., Wynn, J.G., Benefit, B. & McCrossin, M., Paleosols and Paleoenvironments of the Middle Miocene Maboko Formation, Kenya, J. hum. Evol., v.42, p.659–703.

2001. Wynn, J.G. & Retallack, G.J., Middle Miocene Paleosols And Paleoenvironments from The Nyakach Formation at Kaimagool, Southwestern Kenya, J. hum. Evol., v.40, p.263-288.

2000. Wynn, J.G., Paleosols, Stable Carbon Isotopes, and Paleoenvironmental Interpretation of Kanapoi, northern Kenya, J. hum. Evol., v.39, p.411-432.

Research Facilities.

USFSI - USF Stable Isotope Laboratory

 

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