|
|
|
 |
|
|
Emily Moriarty Lemmon
emlemmon@ucdavis.edu Degrees:2000 B.S. Saint Marys College Notre Dame2007 Ph.D. University of Texas Austin Selected Publications:E. Moriarty Lemmon, A. R. Lemmon, J. T. Collins, and D. C. Cannatella. In review. A new North American chorus frog species (Amphibia: Hylidae: Pseudacris) from the south-central United States. ZOOTAXA.A. R. Lemmon and E. Moriarty Lemmon. In press. A likelihood framework for estimating phylogeographic history using geographically continuous genetic data. SYSTEMATIC BIOLOGY. E. Moriarty Lemmon, A. R. Lemmon, and D. C. Cannatella. 2007. Geological and climatic forces driving speciation in the continentally distributed trilling chorus frogs (Pseudacris). EVOLUTION 61:20862103. PDF E. Moriarty Lemmon, A. R. Lemmon, J. A. Lee-Yaw, J. T. Collins, and D. C. Cannatella. 2007. Phylogeny-based delimitation of species boundaries and contact zones in the trilling chorus frogs (Pseudacris). MOLECULAR PHYLOGENETICS AND EVOLUTION 44:10681082.PDF E. C. Moriarty. 2005. Pseudacris triseriata species complex. In: Lannoo, M. (Ed.). Amphibian Declines: The Conservation Status of United States Species. University of California Press, Berkley, California. E. C. Moriarty and D. C. Cannatella. 2004. Phylogenetic relationships of North American chorus frogs (Pseudacris). MOLECULAR PHYLOGENETICS AND EVOLUTION 30:409420.PDF A. R. Lemmon and E. C. Moriarty. 2004. The importance of proper model assumption in Bayesian phylogenetics. SYSTEMATIC BIOLOGY 53:265277.PDF D. M. Sever, T. R. Halliday, E. C. Moriarty, and B. Arano. 2001. Sperm storage in the smooth newt (Triturus v. vulgaris) II. Ultrastructure of the spermathecae after the breeding season. ACTA ZOOLOGICA 82:4956. D. M. Sever, E. C. Moriarty, L.C. Rania, and W.C. Hamlett. 2001. Sperm storage in the oviduct of an internally fertilizing frog, Ascaphus truei. JOURNAL OF MORPHOLOGY 248:121. D. M. Sever, T. R. Halliday, V. Waights, J. Brown, H. Davies, and E. C. Moriarty. 1998. Sperm storage in females of the Smooth Newt (Triturus v. vulgaris) I. Ultrastructure of the spermathecae during the breeding season. JOURNAL OF EXPERIMENTAL ZOOLOGY 283:5170. |
|
My research focuses on the process of speciation, from the early stages of allopatric divergence to the
later stages of secondary contact and evolution of reproductive isolation. This work involves integrating behavioral, genetic,
ecological, and geological data to gain a complete picture of how speciation occurs. The empirical system that I use to study
this process is the North American chorus frogs (Pseudacris), a continentally-distributed monophyletic clade of small treefrogs. Currently, my research has several major foci: 1) Elucidating abiotic factors promoting allopatric divergence. A number of geological and climatic factors have been proposed to drive diversification of taxa on the North American continent, including changes in the courses of river systems, uplift of mountain ranges, marine inundation of coastal areas, and expansion of glaciers. Very few studies have tested the timing of these abiotic events against the timing of speciation events in a statistically rigorous fashion. In a recent study, I performed several of these tests using divergence times estimated from a mitochondrial gene tree in Pseudacris. Future work will integrate additional genes (nuclear), test a wider range of abiotic processes, and expand to include additional taxa to look for common phylogeographic patterns. 2) Determining the role of biotic factors (species interactions) in speciation. Several recent studies have suggested that acoustically signaling organisms may divide up acoustic space (partition the acoustic niche) to reduce interference of their signals. The evidence supporting this idea, however, is rather tenuous. Evidence from Pseudacris suggests that sympatric species have more acoustically divergent calls than allopatric species, supporting the hypothesis of acoustic niche partitioning in these frogs. Interestingly, the particular components of the signal used for partitioning the acoustic niche are also more evolutionarily labile across the phylogeny, suggesting that perhaps these characters are under divergent selection. Future research will investigate whether these patterns are the result of species assortment (where only acoustically distinct species become sympatric) or species divergence (where species undergo reproductive character displacement in sympatry). 3) Examining the patterns and processes of speciation in a secondary contact zone. Earlier research on chorus frogs demonstrated a strong pattern of reproductive character displacement at the contact zone between, Pseudacris feriarum and P. nigrita. I further investigated evolution in this contact zone by a) exploring patterns of geographic variation in male signal displacement in sympatry, b) studying evolution of female preferences for male signals in sympatry, c) examining the fitness cost of hybridization, and d) comparing frequencies of hybridization in areas with low behavioral isolation to areas with high behavioral isolation. This research suggests that the outcome of signal displacement in contact zones can vary dramatically across geography, potentially leading to reproductive isolation among sympatric conspecific populations. Additionally, this work suggests that reinforcement is driving reproductive character displacement in this system. Future work will explore geographic variation in fema le preferences and the energetic costs of male signal divergence in sympatry. In addition, I will expand this research to five other contact zones among closely-related chorus frogs species to study hybrid zone structure, the fitness consequences of hybridization, and the evolution of prezygotic isolating mechanisms in sympatry. ***I will be starting a faculty position at Florida State University in 2009, and will begin accepting graduate students in the fall semester of that year. If you are an undergraduate student interested in these types of questions, please contact me. I would be happy to talk to you about joining my lab group. |
|
|
|