Characterizing weak compatibility in terms of weighted quartets
نویسندگان
چکیده
In phylogenetics there are various methods available for understanding the evolutionary history of a set of species based on the analysis of its 4-element subsets. Guided by biological data, such techniques usually require the initial computation of a quartet-weight function, i.e., a function that assigns a weight to each bipartition of each 4-element subset into two parts of size two, from which a phylogenetic tree or network is subsequently deduced. It is therefore of interest to characterize quartet-weight functions that correspond precisely to phylogenetic trees or networks. Recently, such characterizations have been presented for phylogenetic trees. Here we provide a 5-point condition for characterizing more general structures called weakly compatible split systems. Such split systems underly the construction of split networks, a special class of phylogenetic networks. This 5-point condition also yields a new characterization of quartet-weight functions that correspond to phylogenetic trees.
منابع مشابه
Weighted quartets phylogenetics.
Despite impressive technical and theoretical developments, reconstruction of phylogenetic trees for enormous quantities of molecular data is still a challenging task. A key tool in analyses of large data sets has been the construction of separate trees for subsets (e.g., quartets) of sequences, and subsequent combination of these subtrees into a single tree for the full set (i.e., supertree ana...
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