Areas of Expertise
Teaching Responsibilities: Genetics, Evolution, Population Genetics, General Biology I, Current Applications in Biology (Environmental Science), Conservation Biology
Research Interests: Evolutionary Genetics, Speciation, Invasive Species Biology
B.S. Hastings College (1994)
M.S. Eastern Illinois University (1996)
Ph.D University of South Carolina (2002)
I am interested in a variety of evolutionary questions including the genetics and process of speciation, species interactions and hybridization. I currently have several study systems that students in my lab are researching.
One of my study systems involves a hybrid zone between two mussel species (Mytilus edulis and M. galloprovincialis) in Western Europe. My previous work in this system concentrated on the interplay between selection and dispersal in maintaining a stable hybrid population while at the same time keeping the “pure” populations distinct from one another. Dispersal and natural selection were observed using PCR of species-specific genetic markers. Currently I am investigating the mechanisms that lead to the rapid evolution of the reproductive protein M7 lysin and the role this may play in speciation events in marine invertebrates. Specifically, I am interested in how genotype at M7 lysin affects intra- and interspecific fertilization success and whether there are differences in M7 lysin genotype frequencies in different hybrid and non-hybrid mussel populations.
A second area of research that is beginning to take a more prominent place in my laboratory is work on the local invasive green mussel, Perna viridis. Green mussels are native to the Indo-Pacific and have been introduced to several locations in the Caribbean and Florida over the last 15 years. I currently have students studying their reproductive cycle, current distribution and abundance, larval settlement patterns, the genetic structure of introduced and native populations and the effects of cold temperature on survival. These projects involve a significant field component and also laboratory components including DNA sequencing and Western blots of heat shock proteins.
The third current research endeavor involves an assessment of barriers to reproduction (both pre- and post-zygotic) between two species of killifish, Fundulus grandis and Fundulus heteroclitus. These two species overlap in range in northeastern Florida and occupy the same habitats as adults. I am currently researching species-specific larval habitat use to determine whether the two species utilize different habitats for spawning and whether there are temporal differences in spawning time. I also have students making various intra- and interspecific crosses in the laboratory to determine developmental success rates of hybrids relative to larvae of pure species.
A fourth study system involves the investigation of a potential sympatric speciation event in a gall forming fly (Asphondilia borrichiae) in collaboration with Dr. Tony Rossi. These flies deposit their eggs in three different species of plants in the family Asteracea and these plants form large galls in which the fly larvae develop. Laboratory evidence suggests that flies tend to lay their eggs on the same species of plant that they emerged from. Therefore, there may be specific fly races occupying each host plant species that are diverging from each other since they do not typically mate with individuals born on a different host plant species. In order to assess the level of divergence and amount of assortative mating we are assaying the population genetics of fly populations occupying different host plants from various sites using DNA sequencing and AFLP fingerprinting.
Publications & Presentations
Gilg, M.R., E.G. Johnson, J. Gobin, B.M. Bright and A. Ortolaza. Population genetics of introduced and native populations of the green mussel, Perna viridis: determining patterns of introduction. In Press: Biol. Invas.
Stokes, K., P. Stiling, M.R. Gilg and A. Rossi. 2012. The gall midge, Asphondylia borrichiae, (Diptera: Cecidomyiidae): an indigenous example of host–associated genetic divergence in sympatry. Environ.Entomol. 41: 1246-1254.
Urian, A.G., J.D. Hatle and M.R. Gilg. 2011. Thermal constraints for range expansion of the invasive green mussel, Perna viridis, in the Southeastern United States. J. Exp. Zoo. Part A. 315A: 12-21.
Gilg, M.R., E.A. Hoffman, K.R. Schneider, J. Ryabinov, C. Elkhoury and L.J. Walters. 2010. Recruitment preferences of non-native mussels: Interaction between marine invasions and land-use changes. J. Mollus. Stud. 76: 333-339.
Gilg, M.R., E. Lukaj, M. Abdulnour, E. Gonzalez, M. Middlebrook, R. Turner and R. Howard. 2010. Spatio-temporal settlement patters of the non-native Titan Acorn Barnacle, Megabalanus coccopoma, in northeastern Florida. J. Crustacean Biol. 30: 146-150.
Galleher, S.N., M.R. Gilg and K.J. Smith. 2009. Comparison of sub-adult thermal maxima in Fundulus heteroclitus and F. grandis. Fish Physiol Biochem. 10.1007/s10695-009-9347-1
Galleher, S.N., I. Gonzalez, M.R. Gilg and K.J. Smith. 2009. Larvae and juvenile Fundulus heteroclitus abundance and distribution in Northeast Florida Marshes. Southeast Nat. 8: 495-502.
Matthew R. Gilg, M. O’Connor, R. Norris and T.J. Hilbish. 2009. Maintenance of parental populations bordering a blue mussel hybrid zone by post-settlement selection. J. Mollus Stud. 75: 207-214.
Gonzalez, I., M. Levin, S. Jermanus, B. Watson, and M.R. Gilg. 2009. Genetic assessment of species ranges in Fundulus heteroclitus and F. grandis. Southeast Nat. 8: 227-243.
Matthew R. Gilg, R. Sullivan, S. Kirby, L. Knapp and T.J. Hilbish. 2007. Dispersal vs. retention; correspondence of species-specific reproductive cycles and settlement periods in a blue mussel hybrid zone. Marine Ecology Progress Series 351: 151-161.
Matthew R. Gilg and Thomas J. Hilbish. 2003. Dispersal patterns of mussel larvae throughout a hybrid zone in Southwest England. Evolution. 57: 1061-1077.
Matthew R. Gilg and Thomas J. Hilbish. 2003. Geography of marine larval dispersal: Coupling genetics with fine-scale physical oceanography. Ecology. 84: 2989-2998.
Matthew R. Gilg and Kipp C. Kruse. 2003. Reproduction effects lifespan in the Giant Waterbug, Belostoma flumineum. Am. Mid. Nat. 149: 306-319.
Matthew R. Gilg and Thomas J. Hilbish. 2003. Spatio-temporal patterns of larval settlement and genetics in a blue mussel hybrid zone. Marine Biology. 143: 679-690.