The early evolution and radiation of eukaryotes and its relationship to environmental change, and the fossil record of the earliest skeletal animals. Research uses fieldwork, descriptive systematics, comparisons with modern taxa, paleoecological and taphonomic analyses, and stable isotopic studies.
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Porter Lab Publications
* denotes student
Vendrasco, M. J., Kouchinsky, A., Porter, S. M., and C. Fernandez. 2011. Phylogeny and escalation in Mellopegma and other Cambrian molluscs.Palaeontologica Electronica 14(2):11A. link related blog post
Porter, S. M. 2011. The rise of predators. Geology 39:607-608. pdf
Maloof, A.C., Porter, S.M., *Moore, J.L., Dudás, F.Ö., Bowring, S.A., Higgins, J. A., Fike, D. A., , and M. P. Eddy. 2010. The earliest Cambrian record of animals and ocean geochemical change. GSA Bulletin 122 (11/12):1731-1774. pdf
*Moore, J. L. Porter, S. M., Steiner, M., and G. Li. 2010. Cambrothyra ampulliformis, an unusual coeloscleritophoran from the lower Cambrian of Shaanxi Province, China. Journal of Paleontology 84(6):1040-1060. link
Porter, S.M. 2010. Calcite and aragonite seas and the de novo acquisition of carbonate skeletons. Geobiology 8:256-277. link
Vendrasco, M. J., Porter, S. M., Kouchinsky, A. G., Li, G., and C. Z. Fernandez. 2010. Shell microstructures in early mollusks. Festivus 42: 43-54. pdf
Maloof, A. C., Ramezani, J., Bowring, S. A., Fike, D. A., Porter, S. M., and M. Mazouad. 2010. Constraints on early Cambrian carbon cycling from the duration of the Nemakit-Daldynian-Tommotian boundary d13C shift, Morocco. Geology38:623-626. pdf
Johnston, D. T., Poulton, S. W., Dehler, C. M., Porter, S. M., Husson, J., Canfield, D. E., and A. H. Knoll. 2010. An emerging picture of Neoproterozoic ocean chemistry: Insights from the Chuar Group, Grand Canyon, USA Earth and Planetary Science Letters 290: 64-73. link
Halverson, G. P., Hurtgen, M. T., Porter, S. M., and A. S. Collins. 2009. Neoproterozoic-Cambrian biogeochemical evolution. Pp. 351-365 in: Gaucher, C., Sial, A., Halverson, G. P., and H. Frimmel (eds.). Neoproterozoic-Cambrian Tectonics, Global Change and Evolution: A Focus on Southwestern Gondwana.Elsevier, Developments in Precambrian Geology Series. pdf
Vendrasco, M. J., Porter, S. M., Kouchinsky, A. G., Li, G., and C. Z. Fernandez. 2010. New data on molluscs and their shell microstructures from the middle Cambrian Gowers Formation, Australia. Palaeontology 53: 97-135. link
Vendrasco, M. J. Li, G., Porter, S. M., and C. Z. Fernandez. 2009. New data on the enigmatic Ocruranus-Eohalobia group of early Cambrian small skeletal fossils. Palaeontology 52:1373-1396. link
*Nagy, R. M., Porter, S. M., Dehler, C. M., and Y. Shen. 2009. Biotic turnover driven by eutrophication before the Sturtian low-latitude glaciation. Nature Geoscience 2:414-417. link
Porter, S. M. 2008. Skeletal microstructure indicates chancelloriids and halkeriids are closely related. Palaeontology 51(4): 865-879. pdf
Porter, S. M. 2007. Seawater chemistry and early carbonate biomineralization.Science 316:1302. link hi-res figure
Dehler, C. M., S.M. Porter, D. A Sprinkel, and L.D. DeGrey. 2007. The Neoproterozoic Uinta Mountain Group revisited: a synthesis of recent work on the Red Pine Shale and undivided clastic strata, northeastern Utah. Pp. 151-166 in Link, P.K., & Lewis, R. (eds.): Proterozoic Geology of Western North America and Siberia. SEPM Special Publication 86. pdf
Porter, S. M. 2006. The Proterozoic fossil record of heterotrophic protists. In Xiao, S., and Kaufman, A.J. (eds.), Neoproterozoic Geobiology. Geobiology Series. pdf
*Nagy, R.M., and S. M. Porter. 2005. Paleontology of the Neoproterozoic Uinta Mountain Group. In Dehler, C.M., Pederson, J.L., Sprinkel, D.A., and Kowallis, B.J. (eds.), Uinta Mountain Geology. Utah Geological Association Publication 33, p. 49-62. pdf
Dehler, C.M., D. A. Sprinkel, and S. M. Porter. 2005. Neoproterozoic Uinta Mountain Group of northeastern Utah: pre-Sturtian geographic, tectonic, and biologic evolution. In Pederson, J., and Dehler, C.M. (eds.), Interior Western United States. Geological Society of America Field Guide 6, p.1-26. pdf
Porter, S. M. 2004. Halkieriids in Middle Cambrian phosphatic limestones from Australia. Journal of Paleontology78(3): 574-590. pdf
Porter, S. M., A. H. Knoll, and P. Affaton. 2004. Chemostratigraphy of a Neoproterozoic ‘cap’ carbonate from the Volta Basin, West Africa. Precambrian Research 130: 99-112. pdf
Porter, S. M. 2004. Closing the ‘phosphatization window’: implications for interpreting the record of small shelly fossils. Palaios 19: 178-183. pdf
Porter, S. M. 2004. The fossil record of early eukaryotic diversification.Paleontological Society Papers 10: 35-50. pdf
Porter, S. M., R. Meisterfeld, and A. H. Knoll. 2003. Vase-shaped microfossils from the Neoproterozoic Chuar Group, Grand Canyon: a classification guided by modern testate amoebae. Journal of Paleontology 77(3): 409-429. link (jstor)
Porter, S. M., and A. H. Knoll. 2000. Neoproterozoic testate amoebae: evidence from vase-shaped microfossils in the Chuar Group, Grand Canyon. Paleobiology26(3): 360-385. link (jstor)
Karlstrom, K. E., S. A. Bowring, C. M. Dehler, A. H. Knoll, S. M. Porter, D. J. Des Marais, A. B. Weil, Z. D. Sharp, J. W. Geissman, M. B. Elrick, J. M. Timmons, L. J. Crossey, and K. L. Davidek. 2000. Chuar Group of the Grand Canyon: record of breakup of Rodinia, associated change in the global carbon cycle, and ecosystem expansion by 740 Ma. Geology 28: 619-622. pdf
Dehler, C., S. Porter, and K. Karlstrom. 1999. Grand Canyon Supergroup. Grand Canyon River Guides 12(3): 31-35.
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