The evolution of reproductive strategies in tachinid parasitoids
Cerretti, P., J. E. O'Hara, J. K. Moulton, J. Blaschke, and J. Stireman.  2016.  Proceedings: The XXV International Congress of Entomology, Orlando, FL, September 25-30.

Introduction: The oestroid fly family Tachinidae is the most species-rich family of Calyptratae and one of the most diverse lineages of parasitoids. Within the Tachinidae, ovipary (i.e., deposition of unembryonated eggs) is generally interpreted as a plesiomorphic condition with respect to ovolarvipary (i.e., deposition of embryonated eggs), and it is presumed that the latter evolved from the former several times independently. However, recent phylogenetic studies carried out using large morphological and molecular datasets are challenging this view. Methods: Morphology-based analyses, carried out using a dataset of 185 taxa and 130 characters, were conducted by ranking trees according to parsimony score as optimality criterion under different weighting schemes. Molecular analyses were conducted on an alignment of more than 350 taxa and about 6,000 bp of six nuclear genes by ranking trees according to the Maximum Likelihood criterion and by computing the posterior probability distribution of trees with Bayesian methods. Parsimony and ML methods were used for reconstructing character evolution to assess the most likely ancestral states and minimum numbers of transitions. Results/Conclusion: Both morphology-based and molecular analyses reconstructed ovolarvipary as the ancestral reproductive condition within the Tachinidae and support the evolution of ovipary more than once. Morphology-based analyses converge in reconstructing oviparous groups nested within ovolarviparous lineages, whereas molecules suggest dynamic character turn-over in this reproductive trait with ovolarviparous groups re-evolving several times from oviparous groups. We suggest that host transitions may have been the driving force in the evolution of different reproductive strategies through the opening of new adaptive zones.