Log message:
This is a program for estimating rates (r8s) of molecular evolution and \
divergence times on a phylogenetic tree. It implements several methods for \
estimating these parameters ranging from fairly standard maximum likelihood \
methods in the context of global or local molecular clocks to more experimental \
semiparametric and nonparametric methods that relax the stringency of the clock \
assumption using smoothing methods. Its starting point is a given phylogenetic \
tree and a given set of estimated branch lengths (numbers of substitutions along \
each branch). In addition one or more calibration points can be added to permit \
scaling of rates and times to real units. These calibrations can take one of two \
forms: assignment of a fixed age to a node, or enforcement of a minimum or \
maximum age constraint on a node, which is generally a better reflection of the \
information content of fossil evidence. T
erminal nodes are permitted to occur at any point in time, allowing \
investigation of rate
variation in phylogenies such as those obtained from serial samples of viral \
lineages through time. Finally, it is possible to assign all divergence times \
(perhaps based on outside estimates of divergence times) and examine molecular \
rate variation under several models of smoothing.
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