Many marine species are currently undergoing significant range shifts and exceedingly rapid changes in phenotype driven, potentially, by warming, ocean acidification, and human-induced evolution. Dramatic shifts in body size and maturation have been observed in many marine fishes worldwide. There is considerable debate over whether these changes are the result of rapid evolution or physiological responses to changes in environmental variables. Attempts to address these issues typically assume that thermal physiology is fixed or slow to evolve. Transgenerational plasticity (TGP) occurs when the environment experienced by the parents directly translates, without any changes in DNA sequences, into significant changes in offspring. TGP in thermal performance provides a mechanism for a rapid response to climate change that has, to date, been demonstrated only in terrestrial plants. This project will provide the first test of thermal TGP in marine systems and will explore its implications for forecasting responses to human-induced evolution and climate change. First, the PIs will test for thermal TGP in four taxonomically distinct fishes. Then, using sheepshead minnows as a model, they will study the dependence of transgenerational responses on the predictability of the thermal environment and test whether disparate thermal environments select for different levels of TGP. With these data they will develop the first stochastic population model including TGP and use it to understand life history evolution and predict responses to climate change.
Intellectual Merit: The existence of thermal TGP poses a serious challenge to the idea that changes in thermal physiology are slow to evolve and can safely be ignored in modeling population responses to climate change or harvest selection. By extension, virtually all field estimates of heritability and physiological measurements will need to be reconsidered in light of thermal TGP, as will conclusions regarding rapid evolution in shifting environments. The research team has made significant contributions to theoretical and empirical work on the evolutionary, behavioral, and physiological ecology of growth in many different species and environments. Together, the team has substantial prior experience in all aspects of the proposed research and has worked together successfully for many years.
Broader impacts: The research team is strongly committed to outreach and mentoring students from diverse, under-represented backgrounds. Since 2000, they have advised a total of 18 graduate students (45% women or minorities), and mentored 37 undergraduates (54% women or minorities). They have presented their findings in invited lectures, scientific meetings, and public lecture series. The post-doctoral fellow will be active in Stony Brook's Center for Communicating Science and will be a regular participant in the National Ocean Sciences Bowl, aimed at enhancing high school marine education. The PIs will work with UCSC's Institute for Scientist and Engineer Educators (ISEE) to prepare graduate students for their role as future educators, and with UCSC's NSF-supported Robert Noyce Teacher Scholars Program which funds scholarships for students pursuing teaching careers in math and science. Research results will also be brought to the public through the Seymour Discovery Center, a popular public aquarium showcasing research conducted at the adjacent UCSC and NOAA marine labs. The results will be important in conservation, resource management and policy considerations, since they should provide insight into the capacity for rapid adaptation to environmental change (in this case, temperature). Finally, the results of this work could have commercial applications. One example is the multi-billion dollar aquaculture industry, which currently produces more than 50% of fish for human consumption and could benefit from information on how to increase growth by manipulating parental temperature.