Abstract: The evolution of specialized pollination interactions has been traditionally accepted to be driven by the histories of the interacting species, even though other processes such as variations in the abiotic environment still need to be further evaluated. Doing so would allow gaining a better view of the (complementary) effect of both the biotic and abiotic environments on the evolution of species involved in very specialized interactions. In this talk, I will present the work we have been doing on the specialized pollination interaction established between species of the nectarless plant genus Calceolaria and their oil-bees of genera Centris and Chalepogenus. Through several approaches that combine natural history, community surveys, reproductive tests, and geospatial analyses, I will show how both climatic and biotic drivers can affect the evolution of the plant species. Further, I will present current work that seeks to connect our microevolutionary/ecological knowledge to general macroevolutionary patterns in the interacting groups..