Meeting Abstract
We are in an exciting era of development of new and powerful tools for understanding large-scale macroevolutionary patterns. At the same time, we readily acknowledge that most species diversity remains undescribed and seek approaches to accelerate taxonomic descriptions. However, we are also caught in the conundrum of being uncertain how future additions to species diversity will alter the inferences we want to make today. To approach this problem, we utilize previously assembled large-scale phylogenies and ask how diversification statistics based on these phylogenies would be different if “rolled back” to previous time-points in taxonomic knowledge. This work reveals that over multiyear time-scales (especially in recent decades) species are often added non-randomly to the phylogeny. While precise estimates of the tree-shape statistic λ vary through time as species are added, the way in which these values vary over time is similar among different taxonomic groups and provides a framework for assessing the relative completeness of major lineages within a phylogeny. Using this approach, we can estimate when there is sufficient taxonomic knowledge to make macroevolutionary inferences. While it is impossible to predict the effect that discovery of specific lineages will have on large-scale patterns, we can make general predictions about how adding species to a taxon’s phylogeny will alter our inferences depending on its taxonomic history.
