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Alycia L. StigallAlycia L. Stigall

Department Head, Professor
Jones/Bibee Professor

Department of Earth and Planetary Sciences
607 Strong Hall
1621 Cumberland Ave
Knoxville, TN 37996-1410

Phone: (865) 974-5499

My research group explores the influence of biogeography and paleoecology on macroevolutionary phenomena, principally speciation and cladogensis. I am particularly interested in elucidating the long-term impacts of species invasions and the relationship between speciation mode and biodiversity expansions and declines. My students and I employ a variety of quantitative approaches, such as phylogenetic reconstruction and ecological niche modeling, to integrate previously disparate areas of paleontological investigation within a comprehensive evolutionary framework. Articulated brachiopods are the most commonly employed model taxa within this work.

A secondary line of research involves taxonomic and paleoecological analyses of spinicaudatan crustaceans, a group restricted to freshwater lake environments.

Recent projects have focused on the Great Ordovician Biodiversification Event, the Late Ordovician Richmondian Invasion, the Late Devonian Biodiversity Crisis, and Jurassic lakes of Gondwana. Primary field locations range from the Appalachian and Cincinnati basins, to Oklahoma, Estonia, Namibia, and Antarctica. Our research has been supported by the National Science Foundation, National Geographic, UNESCO, and the American Chemical Society’s Petroleum Research Fund.

• PhD Geology, 2004, University of Kansas
• MS Geology, 2001, University of Kansas
• BS Geological Sciences, 1999, The Ohio State University
• BS Biology, 1999, The Ohio State University

Google Scholar

Outreach Websites/Apps

Digital Atlas of Ancient Life
, Version 2.0: free iOS and Android app, released December 2019.
Stigall, A.L. 2013-present. Atlas of Ordovician Life: Exploring the fauna of the Cincinnati Region.
Hendricks, J.R. Lieberman, B.S., Stigall, A.L. 2013-present. The Digital Atlas of Ancient Life.

Selected peer-reviewed articles

  • McLaughlin, P.I., Stigall. A.L. In review. The Ordovician of the conterminous United States. A Global Synthesis of
    the Ordovician System, Part 1. Geological Society of London.
  • Purcell, C.K.Q., Stigall. A.L. 2021. Ecological niche evolution, speciation, and feedback loops: investigating factors promoting niche evolution in Ordovician brachiopods of Laurentia. Palaeogeography, Palaeoclimatology, Palaeoecology, 578: 110555.
  • Gallego, O.F., Monferran, M.D., Stigall, A.L., Zacarias, I.A., Hegna, T.A., Jiménez, V.C., Bittencourt, J., Li, G., Barrios Calathaki, H.G. 2020. The Devonian-Cretaceous fossil record of “conchostracans” of Africa and their paleobiogeographic relationships with other Gondwanan faunas. Journal of African Earth Sciences, 161: 103648.
  • Stigall, A.L. 2019. The invasion hierarchy: ecological and evolutionary consequences of invasions in the fossil record. Annual Review of Ecology and Evolutionary Systematics, 50: 355-380. https://doi/10.1146/annurev-ecolsys-110617-062638
  • Stigall. A.L. Edwards, C.T., Freeman, R.L., Rasmussen, C.M.Ø. 2019. Coordinated biotic and abiotic change during the Great Ordovician Biodiversification Event: Darriwilian assembly of early Paleozoic building blocks. Palaeogeography, Palaeoclimatology, Palaeoecology, 530: 249-270.
  • Stigall, A.L., Fine, R. 2019. Epibole vs. ecological turnover: contrasting ecosystem impacts of biotic invasions on Ordovician communities.  Palaeoworld, 18: 166-172.
  • Epa, Y.R., Stigall, A.L., Roberts, E.M., O’Brien, H.D., Stevens, N.J. 2018. Morphological diversification of ampullariid gastropods (Nsungwe Formation, late Oligocene, Rukwa Rift Basin) is coincident with onset of East African rifting” Papers in Palaeontology, 4:327-348.
  • Perera, S.N., Stigall, A.L. 2018. Identifying hierarchical spatial patterns within paleocommunities: An example from the Late Pennsylvanian Ames Limestone of the Appalachian basin. Palaeogeography, Palaeoclimatology, Palaeoecology, 506: 1-11.
  • Lam, A.R., Stigall, A.L., Matzke, N.J. 2018. Dispersal in the Ordovician: Speciation patterns and paleobiogeographic analyses of brachiopods and trilobites. Palaeogeography, Palaeoclimatology, Palaeoecology, 489: 147-165.
  • Nylin, S., Agosta, S., Bensch, S., Boeger, W.A., Braga, M.P., Brooks, D.R., Forister, M.L., Hambäck, P.A., Hoberg, E.P., Nyman, T., Schäpers, A., Stigall, A.L., Wheat, C.W., Österling, M., Janz, N. 2018. Towards a new paradigm for species association dynamics. Trends in Ecology and Evolution, 33: 4-14.
  • Stigall, A.L., Plotnick, R.E., Park Boush, L.E. 2017. The first Cenozoic spinicaudatans from North America. Journal of Paleontology, 91: 467-476.
  • Stigall, A.L., Bauer, J.E., Lam, A.L., Wright, D.A. 2017. Biotic immigration events, speciation and the accumulation of biodiversity in deep time.  Global and Planetary Change, 148: 242-257.
  • Bauer, J.E., Stigall, A.L. 2016. A combined morphometric and phylogenetic revision of the Late Ordovician brachiopod genera Eochonetes and Thaerodonta.  Journal of Paleontology, 90(5): 888-909.
  • Trubovitz, S., Stigall, A.L., 2016. Synchronous diversification among Laurentian and Baltic rhynchonelliform brachiopods: implications for regional vs. global triggers of the Great Ordovician Biodiversification Event. Geology, 44: 742-746.
  • Gavin, D.G., Fitzpatrick, M.C., Gugger, P.F., Heath, K.D., Rodriguez-Sanchez, F., Dobrowski, S.Z., Hampte, A., Hu, F.S., Ashcroft, M.B., Bartlein, P.J., Blois, J.L., Cartstens, B.C., Davis, E.B., de Lafontaine, G., Edwards, M.E., Fernandez, M., Henne, P.D., Herring, E.M., Holden, Z.A., Kong, W-S., Liu, J., Magri, D., Matzke, N.J., McGlone, M.S., Saltré, F., Stigall, A.L., Tsai, Y-H.E., Williams, J.W.  2014. Climate refugia: Using fossils, genetics, and spatial modeling to explain the past and project the future of biodiversity. 2014.New Phytologist, 204: 37-54.


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