I am an evolutionary biologist and ecologist, interested in the causes of underlying patterns of species' abundance and distribution, the scale of local adaptation in plants, and plant mating systems and interactions with pollinators. My current work focuses on the limits of geographic range expansion in plants. I teach a variety of courses at Cornell including: BioEE 7670 Current Topics in Ecology and Evolutionary Biology, and BioEE 7600 Special Topics in Ecology and Evolution: Dissertation Improvement Grant Writing.
My research falls into three areas at the interface of ecology and evolutionary biology. First, my main focus is on the genetic and ecological limits to adaptive evolution, especially in relation to species' range limits. Second, I am interested in the direct and indirect links between species diversity and community change, on the one hand and genetic diversity and evolution within species, on the other. Finally, I have a long-standing interest in interactions between plants and their pollinators and the consequences of these interactions for plant mating system evolution.
- Eisen, K. E., A. C. Wruck, and M. A. Geber. 2020. Floral density and co-occurring congeners alter patterns of selection in annual plant communities. Evolution 74: 1682-1698.
- James, A. R. M., T. E. Burnette, J. Mack, D. E. James, V. M. Eckhart, and M. A. Geber. 2020. Germination predicts spatial distribution and coexistence more than adult hydrological traits do in four closely related annual flowering plants. Journal of Ecology 108: 2584-2600.
- Petipas, R. H., A. C. Wruck, and M. A. Geber. 2020. Microbe-mediated local adaptation to limestone barrens in context dependent. Ecology 101:e03092.
- Eisen, K. E., and M. A. Geber. 2018. Ecological sorting and character displacement contribute to the structure of communities of Clarkia species. Journal of Evolutionary Biology 31:1440-1458.
- Benning, J. W., Eckhart, V. M., M. A. Geber, and D. A. Moeller. 2018. Biotic interactions limit the geographic range of an annual plant: herbivory and phenology mediate fitness beyond a range margin. American Naturalist 192:786-797.
- Moeller, D. A., R. D. Briscoe Runquist, M. A. Geber, C. Goodwillie, A. M. Moe, P-O Cheptou, C. G. Eckert, E. Elle, M. O. Johnston, S. Kalisz, J. K. Kelly, E. Porcher, R. H. Ree, R. D. Sargent, M. Vallejo-Marin, and A. A. Winn. 2017. Global biogeography of mating system variation in seed plants. Ecology Letters 20:375-384.
- Briscoe Runquist, R. D., M. A. Geber, M. Pickett-Leonard, and D. A. Moeller. 2017. Mating system evolution under strong pollen limitation: evidence of disruptive selection through male and female fitness in Clarkia xantiana. American Naturalist 189:549-563.
- Anderson, J. A., V. M. Eckhart, and M. A. Geber. 2015. Experimental studies of adaptation in Clarkia xantiana. III. Phenotypic selection across a subspecies border. Evolution 69:2249-2261.
- Gould, Billie, S. McCouch, and M. A. Geber. 2015. De novo transcriptome assembly and identification of gene candidates for rapid evolution in response to soil aluminum tolerance in Anthoxanthum odoratum at the long-term Park Grass Experiment. PLoS One 10:e0124424; DOI: 10.1371/journal.pone.0124424.
- Moeller, D. A., M. A. Geber, V. M. Eckhart, and P. Tiffin. 2012. Reduced pollinator service and elevated pollen limitation at the geographic range limit of an annual plant. Ecology 93:1036-1048.
- Geber, M. A. Ecological and evolutionary limits on species geographic ranges. 2011. American Naturalist 178:S1-S5.
- Eckhart, V. M, Geber, M. A., Morris, W. F., Fabio, E. S., Tiffin, P. L., and D. A. Moeller. 2011. The geography of demography: Long-term demographic studies and species distribution models reveal a species border limited by adaptation. American Naturalist 178:S26-S43.
- Ellner, S. P., Geber, M. A., and N. G. Hairston Jr. Does rapid evolution matter? Measuring the rate of contemporary evolution and its impacts on ecological dynamics. 2011. Ecology Letters 14:603-614.
- Moeller, D. A., Geber, M. A., and P. L. Tiffin. 2011. Population genetics and the evolution of geographic range limits in an annual plant. American Naturalist 178:S44-S61.