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James Lamsdell


Paleobiology, Paleontology, Arthropods, Macroevolution, Mass extinction, Macroecology, Paleoecology, Phylogenetics

Paleobiology Lab

James Lamsdell, Assistant Professor of Geology


My research interests centre around exploring patterns in macroevolution and macroecology through a phylogenetic framework. My work specifically focuses on Palaeozoic arthropods, with a particular focus on aquatic chelicerates (eurypterids and xiphosurans). I have a specific interest in applying phylogenetic methodologies to fossil groups, both in regard to resolving issues of arthropod systematics and in regard to tackling broader macroevolutionary questions, especially surrounding mass extinction events. My work combines phylogenetic and morphometric analyses to quantify patterns of morphological change in response to extinction events and subsequent recoveries, and compares changes in evolutionary rates and ecological preferences to search for selective patterns across these events and subsequent recoveries. With these data I am able to explore how different evolutionary lineages respond to different extinction forcing mechanisms.

Aside from my work on eurypterids and macroevolutionary research, other research interests include: the importance of lagerstätten for informing on arthropod evolution; studying evidence for arthropod development in the fossil record and the role of heterochrony in arthropod evolution, including the importance of ontogenetic data for phylogenetic analyses and calculations of morphospace; the relationship between diversity, morphological disparity, and ecological variety; and the generality of ecological preferences across and within clades.


Geol 103: Earth Through Time

Geol 331: Paleontology

Geol 632: Paleoecology

Recent Publications

Lamsdell JC, Gunderson GO, Meyer RC. 2019. A common arthropod from the Late Ordovician Big Hill Lagerstätte (Michigan) reveals an unexpected ecological diversity within Chasmataspidida. BMC Evolutionary Biology 19 (8), 1–24.

Plax DP, Lamsdell JC, Vrazo MB, Barbikov DV. 2018. A new genus of eurypterid (Chelicerata, Eurypterida) from the Upper Devonian salt deposits of Belarus. Journal of Paleontology 92, 838–849.

Congreve CR, Falk AR, Lamsdell JC. 2018. Biological hierarchies and the nature of extinction. Biological Reviews 93, 811–826.

Rubin M, Lamsdell JC, Prendini L, Hopkins MJ. 2017. Exocuticular hyaline layer of sea scorpions and horseshoe crabs suggests cuticular fluorescence is plesiomorphic in chelicerates. Journal of Zoology 303, 245-253.

Lamsdell JC, Congreve CR, Hopkins MJ, Krug AZ, Patzkowsky ME. 2017. Phylogenetic Paleoecology: tree-thinking and ecology in deep time. Trends in Ecology and Evolution 32, 452–463.