Postdoctoral Researcher
University of Texas at Arlington
Arlington, TX 76019
Research Interests:
I am an organismal evolutionary biologist, and work broadly in the areas of ecology and evolution to understand the processes that drive phenotypic and lineage diversification in reptiles and amphibians. I investigate these topics across different evolutionary time scales, from the differentiation of populations to the diversification of entire clades, using empirical systems I have developed through my field biology program in the Afrotropics. I use emerging genomic approaches to establish the evolutionary framework for these systems, and I generate complementary data through additional molecular techniques, field observations, and by leveraging museum collections. Museum science is essential for my research, and I actively build new resources through biodiversity surveys and specimen collection.
Publications:
Portik, D.M., and D.C. Blackburn. 2016. The evolution of reproductive diversity in Afrobatrachia: A phylogenetic comparative analysis of an extensive radiation of African frogs. Evolution 70: 2017–2032.
Portik, D.M., Smith, L.L., and K. Bi. 2016. An evaluation of transcriptome-based exon capture for frog phylogenomics across multiple scales of divergence (Class: Amphibia, Order: Anura). Molecular Ecology Resources 16: 1069–1083.
Portik, D.M., Jongsma, G.F., Kouete, M.T., Scheinberg, L.A., Freiermuth, B., Nkonmeneck, W.P.T., and D.C. Blackburn. 2016. A survey of amphibians and reptiles in the foothills of Mount Kupe, Cameroon. Amphibian and Reptile Conservation 10(2) [Special Section]: 37–67 (e131).
Medina, M.F., Greenbaum, E., Bauer, A.M., Branch, W.R., Schmitz, A., Conradie, W., Nagy, Z.T., Hibbitts, T.J., Ernst, R., Portik, D.M., Nielsen, S.V., Kusamba, C., Colston, T.J., and M. Behangana. 2016. Phylogeny and systematics of Panaspis and Afroablepharus skinks (Squamata: Scincidae) in the savannas of sub-Saharan Africa. Molecular Phylogenetics and Evolution 100: 409−423.
Dowell, S.A., Portik, D.M., de Buffrénil,V., Ineich, I., Greenbaum, E., Kolokotronis, S.-O., and E.R. Hekkala. 2016. Molecular data from contemporary and historical collections reveal a complex story of cryptic diversification in the Varanus (Polydaedalus) niloticus species group. Molecular Phylogenetics and Evolution 94, Part B: 591−604.
Evans, B.J., Carter, T.F., Gvoždík, V., Kelley, D.B., McLaughlin, P.J., Pauwels, O.S.G., Portik, D.M., Stanley, E.L., Tinsley, R.C., Tobias, M.L., and D.C. Blackburn. 2015. Molecules, morphology, and historical records distinguish six new polyploid species of African clawed frog (genus Xenopus, family Pipidae). PLoS One 10: e0142823.
Portik, D.M., Scheinberg, L., Blackburn, D.C., and R.A. Saporito. 2015. Lack of defensive alkaloids in the integumentary tissue of four brilliantly colored African Reed Frog species (Hyperoliidae: Hyperolius). Herpetological Conservation and Biology 10: 833−838.
Portik, D.M., and T.J. Papenfuss. 2015. Historical biogeography resolves the origins of endemic Arabian toad lineages (family Bufonidae): Evidence for ancient vicariance and dispersal events with the Horn of Africa and South Asia. BMC Evolutionary Biology 15: 152.
Loader, S.P., Lawson, L.P., Portik, D.M., and M. Menegon. 2015. Three new species of spiny throated reed frogs (Anura: Hyperoliidae) from Evergreen forests of Tanzania. BMC Research Notes 8: 167.
Reilly, S.B., Portik, D.M., Koo, M.S., and D.B. Wake. 2014. Discovery of a new, disjunct population of a narrowly distributed salamander (Taricha rivularis) in California presents conservation challenges. Journal of Herpetology 48: 371−379.
Portik, D.M., Travers, S.L., Bauer, A.M., and W.R. Branch. 2013. A new species of Lygodactylus (Squamata: Gekkonidae) endemic to Mt. Namuli, an isolated ‘sky island’ of northern Mozambique. Zootaxa 3710: 415−435.
Portik, D.M., Mulungu, E., Sequeira, D., and J.P. McEntee. 2013. Herpetological surveys of the Serra Jeci and Namuli massifs, Mozambique, and an annotated checklist of the Southern Afromontane Archipelago. Herpetological Review 44: 394−406.
Penner, J., Adum, G.B., McElroy, M.T., Doherty-Bone, T., Hirschfeld, M., Sandberger, L., Weldon, C., Cunningham, A.A., Ohst, T., Wombwell, E., Portik, D.M., Reid, D., Hillers, A., Ofori-Boateng, C., Oduro, W., Plötner, J., Ohler, A., Leaché, A.D., and M.O. Rödel. 2013. West Africa – A safe haven for frogs? A sub-continental assessment of the chytrid fungus (Batrachochytrium dendrobatidis). PLoS One 8: e56236.
Portik, D.M., and A.M. Bauer. 2012. Untangling the complex: molecular relationships among Trachylepis variegata and T. punctulata. African Journal of Herpetology 61: 128−142.
Portik, D.M., and T.J. Papenfuss. 2012. Monitors cross the Red Sea: The biogeographic history of Varanus yemenensis. Molecular Phylogenetics and Evolution 62: 561−565.
Portik, D.M., Wood Jr., P.L., Grismer, J.L., Stanley, E.L., and T. R. Jackman. 2012. Identification of 104 rapidly-evolving nuclear protein-coding markers for amplification across scaled reptiles using genomic resources. Conservation Genetics Resources 4: 1−10.
Portik, D.M., Bauer, A.M., and T. R. Jackman. 2011. Bridging the gap: Western rock skinks (Trachylepis sulcata) have a short history in South Africa. Molecular Ecology 20: 1744−1758.
Portik, D.M., Bauer, A.M. and T.R. Jackman. 2010. The phylogenetic affinities of Trachylepis sulcata nigra and the intraspecific evolution of coastal melanism in the Western rock skink. African Zoology 45(2): 1−13.
Sheil C.A., and D.M. Portik. 2008. Formation and ossification of limb elements in Trachemys scripta and a discussion of autopodial elements in turtles. Zoological Science 25: 622−641.