Tom developed deep learning models that detect the invasive plant, leafy spurge, from publicly-available satellite images. This fine-scale level of detection opens new doors for tracking population dynamics through time and developing better distribution models. The paper was highlighted in local TV news (KARE11) and other science news outlets (AAAS, Phys.org, Biotechniques, etc).
As an undergraduate at UMN, Adam conducted a greenhouse experiment to examine whether parallel adaptation has occurred in response to urban environments of St. Louis, MO and Minneapolis-St. Paul. He also tested whether phenotypic variance is greater among urban than rural populations due to the high heterogeneity of environments and management practices in urban areas.
Kostanecki, A., A.J. Gorton, & D.A. Moeller. 2021. An urban-rural spotlight: evolution at small spatial scales among urban and rural populations of common ragweed. Journal of Urban Ecology 7:doi.org/10.1093/jue/juab004. pdf
One of John’s dissertation projects examined the role of plant-microbe interactions in modulating fitness within versus beyond the range margin of Clarkia xantiana ssp. xantiana. He used a field transplant experiment, involving soil transplants as well, a greenhouse experiment, and microbiome characterization of roots and rhizosphere. His results suggest that there is mutualist limitation and pathogen escape beyond the range margin. This is among the first studies to examine these phenomena in the field.
Benning, J.W., & D.A. Moeller. 2021. Microbes, mutualism, and range margins: testing the fitness consequences of soil microbial communities across and beyond a native plant’s range. New Phytologist 229:2886-2900.
Lauren Ruane and her students at Christopher Newport University conducted very detailed experiments documenting trait variation and its functional consequences across the geographic range of Clarkia xantiana ssp. parviflora, which is a primarily selfing plant. Floral and mating system variation in selfing taxa is often ignored and assumed not to have important consequences. Our results show considerable variation in the opportunity for outcrossing, the time period during which a plant has the capacity to outcross prior to the deposition of self pollen. In addition to protandry, delayed stigma receptivity differed substantially among some populations, providing a second mechanism for delaying selfing.
Ruane, L., S. Magnum, K.W. Horner, & D.A. Moeller. 2020. The opportunity for outcrossing varies across the geographic range of the primarily selfing Clarkia xantiana ssp. parviflora. American Journal of Botany 107:1198-1207. pdf
Amanda worked with the Tiffin lab, especially Tuomas Hamala, to analyze transcriptomes from across the north-south extent of the geographic range of common ragweed. They identified loci bearing footprints of local adaptation, and then use genotype-expression mapping and co-expression networks to infer the connectivity of the genes. The results indicate that the putatively adaptive loci are highly pleiotropic, as they are more likely than expected to affect the expression of other genes, and they reside in central positions within the gene networks.
Hämälä, T., A.J. Gorton, D.A. Moeller, & P. Tiffin. 2020. Pleiotropy facilitates local adaptation to distant optima in common ragweed (Ambrosia artemisiifolia). PLoS Genetics 16:e1008707. pdf
Taz received a 3-year fellowship from NSF to pursue her research on the contribution of genetic and environmental factors to the assembly of foliar endophyte microbiomes in Clarkia xantiana. Congrats Taz!!
John William received a highly-competitive postdoctoral fellowship from NSF. John will continue his work on the evolution of geographic range limits with Topher Weiss-Lehman and Ruth Hufbauer, using experimental evolution to test fundamental theoretical models.
Shelley Sianta started as a postdoc with the Brandvain and Moeller labs to work on evolutionary theory and population genomics of plant speciation. She comes to UMN from UC Santa Cruz where she completed her PhD in Kathleen Kay’s lab. Her dissertation examined adaptive divergence and speciation in the California serpentine flora.
Ryan, Amanda, and Dave worked with other UMN collaborators on a synthesis of local adaptation that compares the strength of local adaptation to abiotic versus biotic environments. It also examines the latitudinal variation in the strength of the effects of abiotic and biotic environments on fitness. It combines a quantitative meta-analysis of published datasets with a qualitative metasynthesis, which systematically examines the text of those published papers. This mixed-methods approach has not been used in ecology and evolutionary biology but has begun to emerge in other scientific literatures.
Check it out here!