Bulletin of Mathematical Biology

, Volume 80, Issue 9, pp 2338–2348 | Cite as

When is a Phylogenetic Network Simply an Amalgamation of Two Trees?

  • Charles SempleEmail author
  • Jack Simpson
Original Article


Phylogenetic networks generalise phylogenetic (evolutionary) trees by allowing for the representation of reticulation (non-treelike) events. The structure of such networks is often viewed by the phylogenetic trees they embed. In this paper, we determine when a phylogenetic network \({\mathcal {N}}\) has two phylogenetic tree embeddings which collectively contain all of the edges of \({\mathcal {N}}\). This determination leads to a polynomial-time algorithm for recognising such networks and an unexpected characterisation of the class of reticulation-visible networks.


Phylogenetic networks Reticulation-visible networks Stack-free networks Tree-based networks 

Mathematics Subject Classification

05C85 92D15 


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Copyright information

© Society for Mathematical Biology 2018

Authors and Affiliations

  1. 1.School of Mathematics and StatisticsUniversity of CanterburyChristchurchNew Zealand

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