The idea of using parasites (and mutualists) to help analyze host history [32] is validated in this case study.
This implies that the migration rate between subpopulations may, in some infectious agents, depend on the host history.
The third phase involves both the host (history and mobilization ability) and the performance of the apheresis procedure (apheresis volumes, timing of collections, efficiency, and so on).
Thus, as a final test for incongruence between HEG and host histories, we used a non-parametric version of Huelsenbeck and Bull's likelihood ratio test for conflicting phylogenetic signal [18].
Lineages that had gone through a single-host or an alternate-host evolutionary history during the first phase of experimental evolution do not show significant differences between each other and in particular the "alternate-host" evolutionary history do not show characteristics of a better adaptation to the new common host, N. tabacum, as predicted by theoretical models [ 33, 34].
It is now admitted that symbionts are deeply involved in the evolutionary process of their hosts and that variations in symbiont genotypes may trigger more important differences in host life history traits than variations of the host genotypes themselves [1].
In theory, parasites can cause divergent selection on their hosts by affecting tradeoffs between host life history and immune defense [16] [18].
We then looked at how parasitism and intraspecific competition among hosts could interact in shaping host life history traits (Bedhomme et al. 2005).
Due to original antigenic sin, other phenotypes in the host immune history may have a disproportionate effect on host immunity.
In addition, considering symbioses using phylogenetic approaches can yield insight into symbiont effects on host niche within the broader context of host evolutionary history (Poisot et al. 2011).
Most of the studies investigating the relationship between hosts and pathogens have focused on the direct effects that pathogens have on host life history traits, usually including measures such as body length, body weight, growth rate, or survival [2].
