Title: “Uncovering adaptive genes and speciation dynamics in a finely-resolved, 20,000-year fossil sequence of a Miocene threespine stickleback fish”
Abstract: Studies of rapid responses to ecological change are mostly limited to the human timescales of a given study, years to decades at most. Thus, it can be difficult to determine the speed, process, and permanence of microevolutionary changes like adaptation and speciation. As such, there is an evidentiary disconnect between microevolutionary processes and macroevolutionary patterns. We need to observe more time to connect the two. Fossils provide a possible solution, especially varved deposits that provide access to 10s of thousands of years fine resolution. One such system is the threespinse stickleback fish sequence from diatomite deposits in hazen Nevada. Resolution is likely annual; we have access to 100,000 years of rock, and fish fossils are highly abundant, allowing for population biology in the fossil record. In this talk, I will discuss two studies from this stickleback lineage about the inference of the genetic basis of adaptation, and the speed and permanence of speciation. Then I will provide some preliminary results from our reconstruction of the lake environment that these fish were evolving in. With luck, I will be able to make some connections to macroevolutionary patterns in the broader stickleback radiation.
Bio: Dr. Stuart is an evolutionary ecologist. He completed his undergraduate education at University of California Davis, where he studied barnacle population genetics in California's rocky intertidal. He completed his PhD at Harvard University where he studied Anolislizard interactions in Mosquito Lagoon, FL. He completed his postdoc at the University of Texas at Austin, where he studied threespine stickleback fish populations in Vancouver, Canada. He currently runs a lab at Loyola University Chicago, with active projects in threespine stickleback fossils from Nevada and the use of eDNA to study fish diversity in Illinois.
