I just had a paper published online in BMC Evolutionary Biology.
This was a fun project. It's essentially showing how the basic models of selection in population genetics play out in detailed phylogenies, where the passage of time is clearly evident. I think a visual / phylogenetic approach really helps to understand the processes at work. In this case, rather than describing an allele that reaches 100% frequency, the process of fixation describes a lineage that outcompetes its contemporaries and comes to be the progenitor of the entire future population. A fundamental finding in population genetics is that selection reduces effective population size, that is when there is heritable variation for fitness, then the patterns of ancestry connecting individuals will resemble a smaller population. Essentially, only a few fitter individuals have a chance of contributing their genetic legacy to the future population. This paper explores the effects of selection on phylogeny shape, with particular attention to uncovering selective dynamics through time.