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Message: <blockquote data-quote="l_raty" data-source="post: 3393779" data-attributes="member: 24811">Re. dating:If Warren et al's tree is misrooted (which it clearly is IMO), and if they used this tree to date the divergence events, you can't expect their dates to be correct.As can be seen, the "basal" branches in their tree (the ones leading to the outgroup taxa) become shorter and shorter as you go up -- this is not real, just a consequence of the internodal divergences in this part of the tree being counted in the wrong direction. A dating algorithm will of course force all of the terminals to end up synchronous (all the samples are present specimens). To make, i.a., Malimbus and Ploceus bicolor present taxa, the algorithm will have to stretch (= assume a rate of change lower than real) the branches that lead to them, and shrink (= assume a rate of change higher than real) the internodes that are between node [6] (date fixed by the authors as 0.5 MYA) and what is accepted as the root of the tree. As a result, the nodes that are between node [6] and the real root of the tree should be expected to have their age underestimated.</blockquote>