A novel time-structured framework to account for the cryptic effects of temperature fluctuations on population dynamics

Although it is well established that temperature extremes associated with heatwaves or cold snaps can have strong and immediate impacts on biological populations, much less is known about the longer-term effects of these short-term events. The investigators are filling this critical knowledge gap by conducting a series of laboratory experiments and developing a new set of mathematical models to identify how temperature fluctuations influence population growth and size.

Additionally, the mathematical models are being extended to generate a baseline understanding of how changes in temperature anticipated under global climate change will likely affect populations around the globe over the course of the 21st century. This project addresses important societal needs by cross-training graduate students in biology, statistics, mathematical modeling, and computer programming.

The results of this research are being integrated into undergraduate courses in biostatistics, mathematical modeling, and environmental science in order to demonstrate the importance of quantitative and interdisciplinary STEM training for addressing important questions in biology. Finally, multiple interactive web modules are being created to disseminate the results of this research beyond academic circles, including Northeastern University’s K-12 outreach programs.

Current empirical and theoretical approaches do not account for the cryptic population structure that emerges when organisms are exposed to variable temperature regimes. The investigators are addressing this limitation by using marine algae as a model system to (i) establish an empirical protocol for properly evaluating the effects of temperature variability on population growth, (ii) develop a novel mathematical modeling framework for accurately predicting the dynamics of populations exposed to temperature fluctuations, and (iii) determine species extinction risk under future ocean temperatures.

Overall, this project is expected to yield a new set of empirical and theoretical tools to better forecast the biological effects of environmental change.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.