This is a weak wrapper around ape's
drop.tip. Importantly, if asked to drop no species
from a phylogeny, it will just return the phylogeny (not an empty
phylogeny, as drop.tip) will.
Usage
drop_tip(tree, spp)
Value
phylo object
Arguments
tree
An phylo object
spp
A vector of species (one, many, or none) to be removed
from tree