I am interested in the mechanisms of evolution, and in particular in how different forces (e.g., different forms of selection, demography) shape a species evolution.
The main objective of my current research project is to analyze the gene expression profile of two ant species (the fire ants Solenopsis invicta and S. richteri) and in their hybrids. The ant system represents an ideal system to study the relationship between genotype and phenotype and how conflicts between selfish replicating units are resolved. The separation of reproductive and working castes is favored by the direct and indirect benefits of the related individuals. However, the evolutionary history of a species is linked to the different selective pressures experienced by each caste and to the way they have been resolved within the species.
I will use DNA microarrays to analyze gene expression in queens, workers and males, in the two parental species and in the hybrids. Furthermore, I will focus my attention on transcripts that are differently expressed in pure species relative to the hybrids, to pinpoint genes and pathways involved in the species' divergence. In this way, we can infer the relative role of each caste separately as selective units in driving the evolution of the species.
The results will also be useful to understand the evolutionary mechanisms of speciation, by evaluating the importance of the divergence in regulatory sequences (which can, for example, disrupt particular pathways in hybrids).