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Melissa Shellman
Assistant Professor
Department of Biology
212 Science Center
PO Box 5805
Clarkson University
Potsdam, NY 13699-5805

Phone: 315-268-4401
Fax: 315-268-7118

Ph.D., Washington University – Evolutionary and Population Biology (2001)

Courses taught
BY140 Life's Diversity
BY314/BY514 Bioinformatics
BY318/STAT318 Biostatistics
BY420/BY620 Evolution

Research Interests
My research seeks to elucidate evolutionary patterns and processes at multiple levels of the biological hierarchy. Thus, projects in my lab are diverse and include evolution of mitochondrial gene order, population genetics, phylogenetics, and macroevolutionary trends of adaptive radiation. This work has focused on but is not restricted to amphibians and reptiles. Current projects include (1) Molecular phylogenetics and evolution of lizards and snakes of the world. (2) Comparative analysis of adaptive radiations. (3) Theory and methods applying the molecular clock and alternative hypothesis testing in phylogenetics. Each of these projects requires significant biological information using empirical and simulated data with broad opportunities for the use and development of bioinformatics resources.

Iguanian lizard phylogenetic systematics. Iguanian lizards, comprised of the clades Iguanidae and Acrodonta, are the most species-rich and ecologically diverse lizard clades in the world. More than 1400 species are distributed worldwide in almost every habitat exhibiting extensive variation in morphology, ecology, life history and behavior. Therefore, a well-corroborated phylogenetic hypothesis is essential for translating these traits into broad evolutionary patterns. I use various forms of data including morphology, behavior, and mitochondrial and nuclear DNA in a rigorous statistical framework to reconstruct the phylogeny of this group.

Macroevolutionary patterns of diversification. Identifying general properties of adaptive diversification has been a fundamental goal of biologists for almost two centuries. The goal of this project is to document the history of cladogenesis and morphological diversification of extant lineages. Paleontological work addressing morphological and species diversity patterns through time have shown a rapid increase in morphological diversity with a concomitant rapid increase in species diversity early in a radiation. Preliminary studies using four species-rich clades of iguanian lizards in a phylogenetic framework has shown that although patterns of morphological and species diversification were unique, a strong negative correlation was found between rapid increases in species diversity and within-clade morphological disparity. This study represents the first of its kind using living taxa. Future work will combine phylogenetic, morphometric, morphological, and ecological data for a much larger sampling of clades to test alternative hypotheses of diversification. This work will set the foundation for future studies on many living organisms to both understand the origins of present-day biodiversity and the current directions of evolutionary change in modern global ecosystems.

Theoretical and applied phyloinformatics. Rapidly expanding genetic databases and the wide array of techniques to analyze those data has made bioinformatics one of the most exciting fields of modern scientific research. However, making sense of this information influx can be a daunting task for researchers at any level. Often new techniques are proposed that lack a thorough exploration of their validity and generality to explain biological phenomena. My work is currently examining three areas of interest: 1) Application of molecular clock techniques to examine the effect of data set size on age estimates of major animal groups; 2) Theoretical problems with the application of the parametric bootstrap under maximum likelihood as applied in phylogenetic systematics; 3) Application and behavior of modern statistical methods to large DNA data sets.

Research Publications (last 5 years)
J. A. Schulte II, F. Moreno-Roark. "Live birth among iguanian lizards predates Pliocene-Pleistocene glaciations," Proceedings of the Royal Society of London, Biological Sciences, Biology Letters 6: 216-218. 2010.

L. J. Harmon, J. B. Losos, T. J. Davies, R. Gillespie, J. L. Gittleman, W. B. Jennings, K. Kozak, M. McPeek, F. Moreno-Roarck, T. Near, A. Purvis, R. E. Ricklefs, D. Schluter, J. A. Schulte II, O. Seehausen, B. L. Sidlauskas, O. Torres-Carvajal, J. T. Weir, A. Ø. Mooers. "Early bursts of body size and shape evolution are rare in comparative data," Evolution (in press). 2010.

D. C. Collar, J. A. Schulte II, B. C. O'Meara, J. B. Losos. "Habitat use affects morphological diversification in dragon lizards," Journal of Evolutionary Biology 23: 1033-1049. 2010.

G. A. Wyngaard, M. Holynskya, J. A. Schulte II. "Phylogeny of the freshwater copepod Mesocyclops (Crustacea: Cyclopidae) based on combined data, with notes on biogeography," Molecular Phylogenetics and Evolution Available online 1 March 2010. 2010.

J. A. Schulte II, E. M. Cartwright. "Phylogenetic relationships among iguanian lizards using alternative partitioning methods and TSHZ1:  A new phylogenetic marker for reptiles," Molecular Phylogenetics and Evolution 50: 391-396. 2009.

J. A. Schulte II, K. de Queiroz.  "Phylogenetic relationships and heterogeneous evolutionary processes among phrynosomatine sand lizards (Squamata, Iguanidae) revisited," Molecular Phylogenetics and Evolution 47: 700-716. 2008.

L. Revell, M. A. Johnson, J. A. Schulte II, J. J. Kolbe, J. B. Losos. "A phylogenetic test for adaptive convergence in rock-dwelling lizards," Evolution 61: 2898-2912. 2007.

D. Pincheira-Donoso, J. A. Scolaro, J. A. Schulte II. "The limits of polymorphism in Liolaemus rothi: Molecular and phenotypic evidence for a new species of the Liolaemus boulengeri clade (Iguanidae, Liolaemini) from boreal Patagonia of Chile," Zootaxa 1452:25-42 2007.

J. R. Macey, J. A. Schulte II, J. L. Strasburg, J. A. Brisson, A. Larson, N. B. Ananjeva, Y. Wang, J. F. Parham, T. J. Papenfuss. "Assembly of the Eastern North American herpetofauna:  New evidence from lizards and frogs," Proceedings of the Royal Society of London, Biological Sciences, Biology Letters 2:388-392 2006.

J.A. Schulte II, J.R. Macey, T.J. Papenfuss, "A genetic perspective on the geographic association of taxa among arid North American lizards of the Sceloporus magister complex (Squamata: Iguanidae: Phrynosomatinae)," Molecular Phylogenetics and Evolution 39:873-880 2006.

O. Torres-Carvajal, J.A. Schulte II, J.E. Cadle, "Phylogenetic relationships of South American lizards of the genus Stenocercus (Squamata: Iguania): a new approach using a general mixture model for gene sequence data," Molecular Phylogenetics and Evolution 39:171-185 2006.

J.R. Macey, J.A. Schulte II, J.J. Fong, I. Das, T.J. Papenfuss, "The complete mitochondrial genome of an agamid lizard from the Afro-Asian subfamily Agaminae and the phylogenetic position of Bufoniceps and Xenagama," Molecular Phylogenetics and Evolution 39:881-886 2006.

G. R. Zug, H. H. K. Brown, J. A. Schulte II, J. V. Vindum.  "Systematics of the Garden Lizards, Calotes versicolor group (Reptilia, Squamata, Agamidae), in Myanmar: Central dry zone populations," Proceedings of the California Academy of Sciences 57:35-68 2006.

F.B. Cruz, L.A. Fitzgerald, R.E. Espinoza, J.A. Schulte II, "The importance of phylogenetic scale in tests of Bergmann's and Rapoport's rules: lessons from a clade of South American lizards," Journal of Evolutionary Biology 18:1559-1574 2005.