Flagrant flailing and promiscuous pinching: The evolution of courtship display in Melittobia (Hymenoptera: Eulophidae)

Since Darwin, students of evolution have offered conjecture and contrivance to explain the evolution of morphology, physiology, and behavior. A common theme among the explanations of the evolution, particularly within behavioral cascades, is an increase in complexity. Indeed, the current proposed phylogeny of the eulophid wasp Melittobia is founded on the hypothesis that the species that evolved first in this lineage has a male courtship display that is similar to the rest of the Tetrastichinae, while those that evolve subsequently have sequentially evolved more complex displays. To test how male courtship displays have evolved in Melittobia, we created a molecular phylogeny of the genus using Baysian techniques based on the genes ITS1, ITS2, and CO1. On this phylogeny we mapped 5 characteristic behaviors associated with courtship using SIMMAP. We show that, contrary to the previously proposed morphological/behavioral hypothesis, the evolution of courtship display in Melittobia does not follow a trend of increasing complexity, and we suggest that other scala naturae type hypotheses be reassessed.