Constructing Level-2 Phylogenetic Networks from Triplets

  • Leo van Iersel
  • Judith Keijsper
  • Steven Kelk
  • Leen Stougie
  • Ferry Hagen
  • Teun Boekhout
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4955)


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 [18]. 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 non-tree 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.


Polynomial Time Phylogenetic Network Algorithm LEVEL2 Biconnected Component Quartet Topology 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Leo van Iersel
    • 1
  • Judith Keijsper
    • 1
  • Steven Kelk
    • 2
  • Leen Stougie
    • 1
    • 2
  • Ferry Hagen
    • 3
  • Teun Boekhout
    • 3
  1. 1.Department of Mathematics and Computer ScienceTechnische Universiteit EindhovenEindhovenThe Netherlands
  2. 2.Centrum voor Wiskunde en Informatica (CWI)AmsterdamThe Netherlands
  3. 3.Centraalbureau voor Schimmelcultures (CBS), Fungal Biodiversity CenterUtrechtThe Netherlands

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