Michelle Tseng

1. How do species interactions mediate adaptation to new environments?

Global climate change is resulting in increases in mean and variation in temperature. Concurrently, organisms are experiencing novel environments via land-use change and eutrophication.  Can organisms adapt fast enough to respond to these changing environments?  Ongoing projects: How do species interactions such as predator-prey, host-parasite, and competitors, alter short- and long-term adaptation to new environments? What happens to consumer-resource dynamics when the resource adapts to environmental change faster than the consumer does? 

2. Evolution of thermal reaction norms and thermal performance curves

Temperature is a key abiotic factor that regulates individual metabolism, population dynamics, and community structure.  Our research investigates  phenotypic plasticity in response to temperature change and how quickly this plasticity evolves.  An organism's 'fitness' across a range of temperatures is known as the thermal performance curve (TPC). Importantly, TPCs are often incorporated into models that predict species range limits or population responses to climate warming, and a common assumption of these models is that TPCs do not evolve.  We're interested in how quickly, an in what way TPCs evolve in nature.

3. Cascading effects of temperature adaptation through aquatic food webs

We are very interested in the phenomenon that algae/phytoplankton grown at cooler temperatures produce more healthy omega-3 long-chain unsaturated fatty acids. Our recent work has shown that zooplankton show higher population growth and accelerated thermal evolution when they are fed these high-quality cold-adapted phytoplankton. We are ramping up our algae-temperature work to better understand the trophic consequences of algal thermal adaptation.

4. Body size, body size, body size (and cell size)

Body size is arguably the single most important ecological trait.  Given the importance of body size you'd think that natural selection would have settled on one perfect body size.  Curiously, body size varies a lot!  But why?  How important are biotic vs abiotic factors in shaping organism body size? How quickly does body size evolve?  Can we look back in time to figure out key environmental factors that have shaped long-term trends in body size?  Ongoing projects: Using natural history collections, how has insect body size changed over time?  How important is changing climate for shaping variation in insect body size?