I have worked on a diversity of projects spanning many biological fields (population genetics, evolution, ecology, conservation, invasion biology) and systems (terrestrial, marine, plants, vertebrates, and invertebrates). This page highlights my current main research interests and endeavours, but you can find past projects and publications in my CV.
Scales of genotypic and phenotypic divergence in high gene flow marine metapopulations
Complex life cycles. Many marine species have pelagic larvae, which has three major consequences for gene flow: firstly, planktonically dispersing larvae may travel long distances, facilitating high gene flow and panmixia; secondly, dispersal trajectories in the plankton are largely dependent on oceanographic conditions; and thirdly, limitation of dispersal to the larval stage restricts gene flow to early in life.
In addition, the complex life cycles inherent with pelagic and benthic developmental stages can create selective antagonism across ontogeny. This is because different morphologies, behaviours, physiologies, and ecologies required at different life stages must be produced by a single genome within a single individual. Hence, while developmental boundaries might evolve to decouple trait variation across ontogeny, genetic or environmental effects may constrain development independence and cause covariance of trait variation across ontogeny.
Spatially and temporally variable marine environments. The ocean is heterogenous through space and time, which affects the scale at which gene flow and selection occur over. Oceanographic patterns can vary over space and shift through time, which can affect how far larvae are transported and the temporal predictability of dispersal trajectories. Moreover, ecologically relevant environmental differences may occur across broad (100s km) to very fine (meters to 10s m) spatial scales and also vary over time, which affects the spatial and temporal scales on which organisms must respond to selection.
Core research questions. (1) What is the temporal and spatial variability in developmental constraints and what genetic or environmental factors underpin them? (2) What is the spatial and temporal scale of adaptive divergence in marine metapopulations, given their propensity for high gene flow and environmental heterogeneity in the sea? (3) What is the relative role of directly heritable or plastic components to trait variation in high gene flow marine systems?
Afromontane forest ecology
I have worked, and still work, on a variety of projects relevant to the conservation of Afromontane forests and determining how anthropogenic disturbances alter natural ecological processes in these highly threatened systems. I get to be a part of this research through my collaboration with the Nigerian Montane Forest Project at Ngel Nyaki Forest Reserve in the Nigeria-Cameroon Highlands.
Afromontane trees. My work in montane Africa tends to revolve around trees. Trees are foundation species of Afromontane forests, so understanding their ecology for conserving habitat and ecosystem function is paramount. Trees are long lived, so it can take many years following anthropogenic disturbance for appreciable signs of ecological degradation to be detected. Before adult trees disappear, habitat destruction can reduce genetic diversity in local forests, and fragmentation can disrupt pollen and seed dispersal, both of which have long-term conservation genetic implications for population viability.
Secondary seed dispersal. I have a particular interest in tree species with large seeds, which historically have evolved to be dispersed by large frugivorous animals. Large animals are highly sensitive to anthropogenic disturbance and their loss from forests can affect natural seed dispersal processes and hence recruitment of new individuals into the population. Increasing work across the tropics suggests that small granivorous animals might be important in providing supplementary secondary dispersal for large-seeded trees in forests where large frugivores have been extirpated. However, because granivorous mammals prey upon seeds, the interaction between granivores and trees can seesaw between antagonistic (granivores act as predators) and mutualistic (granivores act as dispersers), depending on the ecological context.
Core research questions. (1) What genetic diversity remains in disturbed tree communities and how does habitat fragmentation disrupt gene flow among forest remnants? (2) How does anthropogenic disturbance affect seedling recruitment? (3) What ecological factors determine the nature (antagonistic versus mutualistic) of tree-granivore interactions?