Testing cospeciation through large-scale cophylogenetic studies.

Insects are involved in a multitude of interactions with other organisms, which make them ideal models for large-scale cophylogenetic studies. Once phylogenies of interacting lineages have been inferred, there are a number of questions we may wish to ask, such as what was the relationship between the partners in the past? Have they co-evolved for thousands or millions of years, or has one of the partners switched among different host species? To answer such questions, researchers may conduct cophylogenetic analysis, to explore the relationships between the phylogenies of interacting lineages and determine whether the match is significant or find explanations for observed differences. When combined with dating analyses, cophylogenetic analyses may support cospeciation of the partners or phylogenetic tracking. As they may reveal dynamics of host-pathogen coevolution, cophylogenetic studies may also help tackle global health issues (e.g. document the spread of disease causing pathogens). Cophylogenetic studies of parasitoids and their insect hosts may also help identify effective biocontrol agents. With the advent of next generation sequencing technologies and keeping in mind that systematic errors may occur, cophylogenetics will benefit from better-resolved trees, allowing more accurate reconciliation. However as trees become larger, current algorithms also become more computationally challenging. Nevertheless, both theoretical and methodological developments are leading to more accurate and powerful tests of cospeciation through cophylogenetic analysis.