I am a 4th year biology PhD student at Stanford University. I work mostly at the Department for Plant Biology at the Carnegie Institution for Science's campus located at Stanford. I have a lot of experience in ecology and evolution and have been learning about genomics and bioinformatic tools during my PhD. Before my PhD I worked for the Bureau of Land Management and the National Park Service and as a technician at UC Davis in Dr. Annie Schmitt's lab. All of my previous positions focused on native plant systems, and my PhD is my first time working with Arabidopsis.
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Four range limit hypotheses tested with Arabidopsis in climate manipulated common garden
Laura Leventhal, Megan Ruffley, Moi Exposito-Alonso
A species’ range is a physical representation of the limits of evolution as it epitomizes a species’ evolutionary niche in a specific period of time. Range limits are dynamic barriers affected by the abiotic and biotic environment, population dynamics, and, least well understood, genetic mechanisms. There are currently four hypotheses that best account for the mechanisms behind the formation of range limits. 1) An increase in deleterious mutations at range edges, 2) high levels of maladaptive gene flow 3) dispersal limitation, and 4) the strength of selection is too strong and renders edge population too small to adapt to a changing environment. We tested these hypotheses using an outdoor common garden experiment with a gradient of 14 precipitation treatments and 352 diverse Arabidopsis thaliana accessions on Stanford University’s campus. In total, we planted 25,920 plants in November 2021 and measured fitness and first day of flowering, as well as ecologically-relevant phenotypes such as stomata indices, growth rate, and ∂C13. This experiment will allow us to elucidate which hypothesis or combination of hypotheses contributes the most to the formation of range limits.