My research interests lie at the intersection of ecology and evolution. Primarily, I study the evolution of life histories and the larval ecology of marine invertebrate animals. Invertebrates comprise more than 98% of all known animal species and exhibit a wide variety of reproductive modes and strategies. Most marine invertebrate species possess a complex life cycle that is made up of a benthic adult stage and a planktonic larval stage. There is wide variation in both the form and function of the adult and larval stages of marine invertebrates and often the two stages of the life cycle are extraordinarily dissimilar in their morphology (Fig. 1). My research is focused on explaining the diversity of strategies that organisms use as they switch between habitats and morphologies during their life cycle. In particular, I am interested in investigating how changes in maternal investment affect larval and juvenile development, survival and growth.
Figure 1: One example of a complex life cycle in a marine invertebrate. In this case, a benthic adult brittlestar releases its gametes into the water column where fertilization occurs and development takes place over a period of days to weeks. During this period a planktonic larval stage develops which is morphologically dissimilar from the adult. Eventually the larva settles as a benthic juvenile and the cycle repeats itself in the next generation. This pattern is common among marine invertebrates and the size of the egg is positively correlated with parental investment and predicts the length of the developmental period. Note that the images are not to scale. The adult is many times larger than the egg, larval and juvenile stages.
1) How do changes in maternal investment affect larval and juvenile development, growth and survival?
2) What are the consequences of the habitat shifts associated with complex life cycles for predation rates on the larval and juvenile stages of marine invertebrates?
3) How can intermediate modes of larval development illuminate the evolutionary processes leading to diverse reproductive patterns?
4) How do changes in temperature and salinity influence patterns of development in echinoderms?