Our Aim 1 is to reconstruct the evolutionary history of speciation events, abiotic niches, and biotic interactions for Costus.
This aim will lay the groundwork for our experimental aims below by confirming sister species relationships and providing testable hypotheses about abiotic and biotic factors important in speciation. These analyses will allow us to compare evolutionary rates for abiotic and biotic niches and traits, and examine whether particular biotic and abiotic factors evolve in a correlated fashion that might indicate functional relationships. They will also provide a tropical counterpart to studies of niche divergence in temperate plant speciation (e.g., Anacker & Strauss 2014; Grossenbacher et al. 2014).