Announcement: I will be starting up my lab in Integrative Biology at UC Berkeley in July 2014, so I will be recruiting next summer. Watch this space!
Welcome to my homepage!
Temperature is one of the most important abiotic factors influencing the physiology, ecology, and evolution of ectothermic organisms, and anthropogenic climate change is driving the most rapid changes in thermal conditions in human history. I aim to understand how insects respond to changes in their overwintering thermal environment, on physiological, ecological, and evolutionary scales. My research addresses two main questions:
How do insects respond to thermal change during winter?
Winter
imposes two interacting stresses - cold and resource limitation.
Current climate change projections predict higher average
temperatures, which will mitigate cold stress but increase energetic
stress by raising rates of metabolism in dormant ectotherms, and
also increases in extreme events, which mean that organisms will
have to tolerate an increased incidence of both high and low extreme
temperatures throughout the year. A
lack of insight into the physiological response of insects to winter
climate change is a major impediment to successfully predicting
insect population dynamics in a changing world. I am investigating
the genetic, physiological, and life-history mechanisms by which
insects respond to thermal change over winter using a comparative
approach among species (Pelini
et al. 2009 PNAS, Williams
et al. 2012 Climate Research), between populations of a
species (Williams
et al. 2012 PLoS ONE), and within species (go here
to read about my current work on the physiological and biochemical
architecture of cold tolerance in Drosophila melanogaster).
What is the potential for evolution of these responses?
Differentiation
in metabolic responses to winter climate change occurs over
micro-evolutionary (intra-population) to the macro-evolutionary
(inter-population and inter-specific) scales, and the presence of
heritable variation is a prerequisite for adaptation to climate
change. Understanding the genetic architecture of variation in
winter-relevant metabolic phenotypes such as propensity to
diapause, metabolic rate and thermal sensitivity thereof, and
nutrient storage and mobilization, and the contribution of these
traits to fitness, will therefore advance our ability to predict
population-level responses to winter climate change and explain
global gradients in metabolic physiology. A major focus of my
research is identifying heritable metabolic phenotypes that
accompany thermal adaptation to winter conditions both intra- and
inter-specifically (e.g. Williams
et al. 2012_PLoS ONE).
Background image courtesy of Stock Xchng