timing for early angiosperm diversification, or that there are historical patterns to changes
in the rate of molecular evolution that we still know little about. This last possibility
should be evaluated, and the least we should do is to quantify the consequences of
accepting the fossil-based estimates.
AcknowledgementsThis research was supported by a Marie Curie Fellowship of the European Community
Programme Improving Human Research Potential and the Socio-Economic Knowledge
under contract number HPMFCT-2000–00631 to N.Wikström.
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