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Issue No.04 - October-December (2009 vol.6)

pp: 667-681

Judith Keijsper , Technische Universiteit Eindhoven, Eindhoven

Steven Kelk , Centrum voor Wiskunde en Informatica (CWI), Amsterdam

Leen Stougie , Centrum voor Wiskunde en Informatica (CWI) and Free University, Amsterdam

Ferry Hagen , Centraalbureau voor Schimmelcultures (CBS), Utrecht

Teun Boekhout , Centraalbureau voor Schimmelcultures (CBS), Utrecht

DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TCBB.2009.22

ABSTRACT

Jansson and Sung showed that, given a dense set of input triplets T (representing hypotheses about the local evolutionary relationships of triplets of taxa), it is possible to determine in polynomial time whether there exists a level-1 network consistent with T, and if so, to construct such a network [24]. Here, we extend this work by showing that this problem is even polynomial time solvable for the construction of level-2 networks. This shows that, assuming density, it is tractable to construct plausible evolutionary histories from input triplets even when such histories are heavily nontree-like. This further strengthens the case for the use of triplet-based methods in the construction of phylogenetic networks. We also implemented the algorithm and applied it to yeast data.

INDEX TERMS

Phylogenetic networks, level-2, triplets, reticulations, polynomial time algorithms.

CITATION

Judith Keijsper, Steven Kelk, Leen Stougie, Ferry Hagen, Teun Boekhout, "Constructing Level-2 Phylogenetic Networks from Triplets",

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