Hi Andrew.
This is because the numbers in tre$edge are node & tip numbers, not tip
labels (which also can be numbers). The translation between tip numbers
and tip labels is given by tre$tip.label. Here, tip labels are indexed
by their numbers in tre$edge.
For instance, in your case we have
Hi all,
While simulating some trees using the birthdeath.tree() function in
geiger I noticed an inconsistency between the node/tip labels in the
edge matrix and in a plot of the tree. I dumped in the text of one of
the trees I produced as an example.
library(ape)
tre<-read.tree(text="8:2.850