Title
Binets: fundamental building blocks for phylogenetic networks.
Abstract
Phylogenetic networks are a generalization of evolutionary trees that are used by biologists to represent the evolution of organisms which have undergone reticulate evolution. Essentially, a phylogenetic network is a directed acyclic graph having a unique root in which the leaves are labelled by a given set of species. Recently, some approaches have been developed to construct phylogenetic networks from collections of networks on 2- and 3-leaved networks, which are known as binets and trinets, respectively. Here we study in more depth properties of collections of binets, one of the simplest possible types of networks into which a phylogenetic network can be decomposed. More specifically, we show that if a collection of level-1 binets is compatible with some binary network, then it is also compatible with a binary level-1 network. Our proofs are based on useful structural results concerning lowest stable ancestors in networks. In addition, we show that, although the binets do not determine the topology of the network, they do determine the number of reticulations in the network, which is one of its most important parameters. We also consider algorithmic questions concerning binets. We show that deciding whether an arbitrary set of binets is compatible with some network is at least as hard as the well-known graph isomorphism problem. However, if we restrict to level-1 binets, it is possible to decide in polynomial time whether there exists a binary network that displays all the binets. We also show that to find a network that displays a maximum number of the binets is NP-hard, but that there exists a simple polynomial-time 1/3-approximation algorithm for this problem. It is hoped that these results will eventually assist in the development of new methods for constructing phylogenetic networks from collections of smaller networks.
Year
DOI
Venue
2017
10.1007/s11538-017-0275-4
Bulletin of mathematical biology
Keywords
Field
DocType
Algorithm,Binet,Phylogenetic network,Reticulate evolution,Subnetwork
Discrete mathematics,Phylogenetic tree,Network motif,Directed acyclic graph,Reticulate evolution,Time complexity,Subnetwork,Mathematics,Graph isomorphism problem,Phylogenetic network
Journal
Volume
Issue
ISSN
abs/1701.08995
5
0092-8240
Citations 
PageRank 
References 
1
0.38
6
Authors
4
Name
Order
Citations
PageRank
Leo van Iersel121524.58
Vincent Moulton233048.01
Eveline de Swart310.38
Taoyang Wu47413.24