divergence times sort of defined

[Bill Adlam <bill.adlam@st-peters.oxford.ac.uk>]

On Mon, 12 Jun 1995, John Schneiderman wrote:

> What is "minimum divergence times for sister-groups"?

If, for example, the oldest fossil from one taxon is dated at 100Ma and the 
oldest from its sister group at 150Ma, the groups must have diverged at least
150MYA and so are both at least 150Ma old.  It is much harder to generate
upper age limits.
                                                                  Bill Adlam