Dr. Lisa Horth
Assistant Professor Biological Sciences
Education:
University of California, Davis Post-doc (2004)
University of Virginia, Post-doc (2001-2003)
Florida State University, PhD (2001)
University of Maryland, College Park, MS and BS.
Research Interests:
Molecular aspects of pigmentation - With Artyom Kopp and Sergey Nuzhdin at UC Davis, I address whether transposons and/or SNPs in bric-a-brac (melanic pigmentation genes) are associated with color variation on the abdomen of female fruit-flies (D.melanogaster). With S. Nuzhdin, I am also involved in a transposon accumulation study in fruit-flies.
Unlike fruit-flies, many organisms express variation in pigmentation due to point mutations in the melanocortin-1 receptor gene (MC1R). I am investigating the potential importance of this gene in fish pigmentation. Mutational data from specific genes that are clearly associated with phenotypic variation is quite valuable since the signature of particular selective regimes that maintain genetic variation can be identified using these data.
Mate choice, population structure and the maintenance of rare gentoypes
I have demonstrated that male mating behavior differs in melanic and wild-type (silvery-gray) mosquitofish. Further, slight changes in the frequency of melanic fish in experimental populations affect the abundance of juveniles and females, along with the numerical dynamics of females. Such changes may in turn, affect population stability.
Melanic males also demonstrate negative frequency dependent survival. Population structure (frequency of melanism) markedly affects population composition in subsequent generations (high initial frequencies of melanism result in much lower frequencies of melanism in the F1 generation, whereas lower relative frequencies remain constant). These patterns have all been identified in short time-frame experiments.
By running longer, larger experiments at multiple melanic frequencies, it will be possible to determine whether melanic males contribute to population stability, and whether an equilibrium frequency results from negative frequency dependent selection. Joe Travis has contributed substantially to this work.
In collaboration with Dave McCauley and Doug Taylor, I address the importance of the epistatic interaction of cytoplasmic male sterility elements with nuclear restoration genes in affecting sex-ratio in structured populations of a weedy plant (Silene vulgaris).
Selected Publications:
Horth, L 2007. Sensory genes and mate choice: Evidence that duplications, mutations, and adaptive evolution alter variation in mating cue genes and their receptors. Genomics 90:(2007) 159-175. Cover illustration.
Horth, L. 2007. Gaining a comprehensive understanding of the role of the heritable molecular genetic variation in mate choice and mating related genes. NOVA Publications.
Horth, L. 2006. A sex-linked allele, autosomal modifiers and temperature-dependence appear to regulate melanism in male mosquitofish. Journal Experimental Biology. 209: 4938-4945.
Bowen, T. & Horth, L. 2005. Use of the Eyeport vision training system to enhance the visual performance of little league baseball players 16: 143-148.
Horth, L. 2005. Melanism and melanocortin-1 receptor mutations in vertebrates. Proc. Indian Natl. Sci. Acad. B70: 499-515.
Horth, L. 2004. Predation and the persistence of melanic male mosquitofish (Gambusia holbrooki). Journal Evolutionary Biology. 17: 672-679.
Horth, L. 2004. A brief description of the courtship display of male pike killifish (Belonesox belizanus). Florida Scientist. 67: 159-165.
Horth, L. 2003. Melanic body-color and aggressive mating behavior are correlated traits in male mosquitofish, (Gambusia holbrooki). Proceedings of the Royal Society. 270: 1033-1040.
Horth, L. & J. Travis. 2002. Frequency-dependent numerical dynamics in mosquitofish. Proceedings of the Royal Society. 269: 2239-2247.
Miller, T., L. Horth. & R. Reeves. 2002. Trophic Interactions in Pitcher Plant Communities. Community Ecology 3: 109-116.
Horth, L. 2002. Mother goose and the kids chase marbled-black mosquitofish. Florida Wildlife Magazine. 56: 26-27.
Kalisz, S., L. Horth & M. McPeek. 1997. Fragmentation and the Role of Seed Banks in Persistence in Isolated Populations of Collinsia verna. In: Conservation in Chronically Fragmented Populations. Ed: Mark Schwartz. Chapman & Hall.
Horth, L. Deme structure and rare male frequency affect fitness in mosquitofish (Gambusia holbrooki) within and among generations.
Horth, L., Taylor, D. & McCauley, D. Epistatic nuclear-cytoplasmic conflict and the restoration of sterility in Silene vulgaris.
Schlitt, J & Horth, L. 2007. Simulation of the transmission of HPV in natural populations.
Kennedy, T., Horth, L. & Carr, D. The foraging preference for exotic over native vegetation in endangered apple snails (submitted).
Manuscripts (Submitted):
Whelan, E. & L. Horth. The role of positive selection in the association between paternal age and disease (Jour Hum Genetics).
Wilk, R. & Horth, L. Melanic male mosquitofish are larger than silver male mosquitofish (Copeia).
Peer-review:
Molecular Biology & Evolution, Evolution, Heredity, Journal of Heredity, Biology Letters, Behavioral Ecology & Sociobiolgy, Oecologia, Biological Journal of the Linnean Society, Biology Letters, Copeia, Frontiers in Zoology, Proceedings of the Indian National Academy of Science.
Links:
Non-Melanicand melanic morphs of live-bearing fish species
People in the Lab
Department of Biological Sciences
Old Dominion University
302 G Mills Godwin Bldg.
Norfolk, VA 23529-0266
Phone: (757) 683-6508
E-mail: lhorth@odu.edu
