The Structure of Level-k Phylogenetic Networks

  • Philippe Gambette
  • Vincent Berry
  • Christophe Paul
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5577)


Evolution is usually described as a phylogenetic tree, but due to some exchange of genetic material, it can be represented as a phylogenetic network which has an underlying tree structure. The notion of level was recently introduced as a parameter on realistic kinds of phylogenetic networks to express their complexity and tree-likeness. We study the structure of level-k networks, and how they can be decomposed into level-k generators. We also provide a polynomial time algorithm which takes as input the set of level-k generators and builds the set of level-(k + 1) generators. Finally, with a simulation study, we evaluate the proportion of level-k phylogenetic networks among networks generated according to the coalescent model with recombination.


Directed Acyclic Graph Lateral Gene Transfer Phylogenetic Network Graph Isomorphism Coalescent Model 
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 2009

Authors and Affiliations

  • Philippe Gambette
    • 1
  • Vincent Berry
    • 1
  • Christophe Paul
    • 1
  1. 1.Département informatiqueL.I.R.M.M., C.N.R.S. - Université Montpellier IIFrance

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