My research interests revolve roughly around the limits to adaptation, whether imposed by ecological and environmental factors or genetic constraints. My goal is to understand the contributions of these to evolutionary processes, and to reconcile observations in the near term (‘microevolution’) with patterns evident at longer timescales (‘macroevolution’). My work has always been inspired by natural history, usually of invertebrate animals. But often, these investigations of the ‘small’ have fed my lifelong fascination with understanding decidedly ‘big’ problems in biology. These days, my focus has been on sharing my love of biology through teaching and outreach, but I do maintain a modest research program, often in collaboration with colleagues, including students.

Scroll over the images below to see some of my main research directions; check out my Teaching & Students page and my Publications page for more details.

Phenotypic Evolution:
Natural selection acts on multiple traits simultaneously. How strong is contemporary selection on suites of traits and how rapid is evolution? How does natural selection that we can measure now (microevolution) translate to what see on 'macroevolutionary' timescales?

Sexual Dimorphism:
Males and females have fundamentally different evolutionary interests, often leading to striking sex-differences in phenotype. How do the sexes manage to diverge despite sharing the same genome? For example, what do alleles that benefit my daughters (female optimum) mean for the success of my sons (male optimum)?

Genetic Architecture:
Evolution is limited by the availability of genetic variance and among-trait correlations. Does this result in strong genetic constraints? How readily do genetic systems evolve? On one hand, it is undeniable that trait combinations evolve/change, but why do some combinations persist for millions of years?

Maintaining Variation:
Strong selection typically reduces genetic variation, yet some species are remarkably variable. What allows such polymorphism to persist? What features of environments or species allow the latter to ‘break these rules’ of variation despite strong selection?

Adaptation:
Evolution can be envisioned as a 'hill-climbing' process on an adaptive landscape, with the ascent relying on the supply of genetic variation (including new mutations). What do landscapes look like and how stable are they? Are there few or many paths towards higher ground? Are paths predictable?


Ecology, Environment and Life History:
Individuals vary in their ability to acquire resources and in how they allocate these. This issue is central to understanding the evolution of life history traits/strategies. How does environmental variation influence trait expression? How do populations adapt to new environments?