My major research
interests are (1) evolutionary genetics, in particular the
wide-ranging ramifications of genetic conflict, and (2) evolutionary ecology, broadly defined to include the interactions
between behaviour, morphology, physiology and genetics
on one hand and the environment on the other. Several current research projects
in my laboratory focus, in one way or another, on understanding the causes and
consequences of interactions between the sexes and the genetic / evolutionary
ramifications of having two sexes.

- Every animal cell contains two types of
genetic material: genes in the nucleus and genes in the mitochondria. The
mitochondrial genome is small but encodes for products that are vital for the
metabolic performance of the cell: the energy producing enzymatic machinery of
the mitochondria is built collectively by products of the mitochondrial and
nuclear genome. MtDNA has long been considered selectively neutral. However,
recent research in our laboratory has demonstrated that mtDNA variation across
and within populations interacts with nuclear genes in affecting important
phenotypic traits such as metabolic phenotypes, development rate and even
fitness. MtDNA does not follow the same evolutionary “rules” as does nDNA, chiefly because it is haploid, does not recombine
and is maternally inherited. There is therefore generally no selection on mtDNA
in males and we are currently exploring the possibility that sexual conflict
over optimal life histories have important consequences for mitonuclear
coevolution.

- A large body of our research revolves,
directly or indirectly, around the causes and consequences of conflicts of
interest between the sexes. Such conflicts can arise because the direction of
selection on an allele at a given locus depends upon in which sex it is
expressed, such that one allele yields highest fitness when expressed in males
and another when expressed in females. Alternatively, sexual conflict can
generate "arms races" between the sexes, known as sexually
antagonistic coevolution. Our empirical work is done primarily with a variety
of different insects. In collaboration with researchers in USA, Canada,
Australia and England, we aim both at characterizing various male-female
conflicts, and at understanding the far-reaching consequences and
coevolutionary dynamics of such conflicts. Below are pictures of three of our
model systems: a Sabethine mosquito where both sexes
carry striking leg ornaments, a male and a female water strider engaged in a
premating “struggle” and a mating pair of seed beetles (Callosobruchus maculatus).
- More than a century after Darwin,
our understanding of the process by which new species are formed is still
incomplete. We are aiming at illuminating the processes involved both in the
evolution of reproductive isolation (speciation) and in evolution leading to
extinction of lineages. We are interested in understanding (1) the evolution of
hybrid inviability, (2) the evolution of "cryptic" reproductive
isolation that occurs after mating, such that females may mate with males of both
their own and other species but yet will produce no or little hybrid offspring,
and (3) how sexual selection contributes to the evolution of species
recognition signals.
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