res the
results. The impact of of a specific clade on model estimates is calculated by the
comparison between the full model (with all species) and the model without 
the species belonging to a clade. It repeats this operation using n trees, 
randomly picked in a multiPhylo file.</p>
<p>Additionally, to account for the influence of the number of species on each 
clade (clade sample size), this function also estimates a null distribution of slopes
expected for the number of species in a given clade. This is 