Who is Who in Phylogenetic Networks

Publications of Simone Linz     Order by:   Type | Year
Associated keywords
agreement-forest approximation APX-hard bound characterization cherry-picking counting database display-set distance-between-networks explicit-network FPT from-network from-rooted-trees from-sequences from-triplets hybridization kernelization lateral-gene-transfer likelihood LST-distance minimum-number normal-network NP-complete parsimony phylogenetic-network phylogeny Program-Clustistic Program-CycleKiller Program-Dendroscope Program-HybridInterleave Program-HybridNumber Program-Hybroscale Program-MaafB Program-PIRN reconstruction reticulation-visible-network rigidly-displaying software SPR-distance statistical-model survey temporal-hybridization-number time-consistent-network tree-based-network tree-child-network uniqueness weakly-displaying
2020
1 Simone Linz and Charles Semple. Caterpillars on three and four leaves are sufficient to reconstruct binary normal networks. In JOMB, 2020. Keywords: explicit network, from rooted trees, from triplets, normal network, phylogenetic network, phylogeny, reconstruction, uniqueness. Note: https://arxiv.org/abs/2002.00483, to appear.         2 Katharina Huber, Simone Linz and Vincent Moulton. Weakly displaying trees in temporal tree-child network. 2020. Keywords: cherry-picking, from rooted trees, phylogenetic network, phylogeny, reconstruction, rigidly displaying, time consistent network, tree-child network, weakly displaying. Note: https://arxiv.org/abs/2004.02634.
2019
3 Simone Linz and Charles Semple. Attaching leaves and picking cherries to characterise the hybridisation number for a set of phylogenies. In AAM, Vol. 105:102-129, 2019. Keywords: agreement forest, cherry-picking, explicit network, from rooted trees, phylogenetic network, phylogeny, reconstruction, tree-child network. Note: https://doi.org/10.1016/j.aam.2019.01.004.         4 Janosch Döcker, Leo van Iersel, Steven Kelk and Simone Linz. Deciding the existence of a cherry-picking sequence is hard on two trees. In DAM, Vol. 260:131-143, 2019. Keywords: cherry-picking, explicit network, hybridization, minimum number, NP complete, phylogenetic network, phylogeny, reconstruction, temporal-hybridization number, time consistent network, tree-child network. Note: https://arxiv.org/abs/1712.02965.         5 Jonathan Klawitter and Simone Linz. On the Subnet Prune and Regraft Distance. In ELJC, Vol. 26(2):P2.3.1-23, 2019. Keywords: agreement forest, explicit network, phylogenetic network, phylogeny, reticulation-visible network, SPR distance, tree-based network, tree-child network. Note: https://arxiv.org/abs/1805.07839.         6 Janosch Döcker, Simone Linz and Charles Semple. Displaying trees across two phylogenetic networks. In TCS, Vol. 796:129-146, 2019. Keywords: display set, explicit network, normal network, phylogenetic network, phylogeny, time consistent network, tree-child network. Note: https://arxiv.org/abs/1901.06612.
2018
7 Daniel H. Huson and Simone Linz. Autumn Algorithm - Computation of Hybridization Networks for Realistic Phylogenetic Trees. In TCBB, Vol. 15:398-410, 2018. Keywords: explicit network, from rooted trees, phylogenetic network, phylogeny, Program Dendroscope, reconstruction. Note: https://simonelinz.files.wordpress.com/2016/06/hl16.pdf.         8 Janosch Döcker and Simone Linz. On the existence of a cherry-picking sequence. In TCS, Vol. 714:36-50, 2018. Keywords: cherry-picking, explicit network, from rooted trees, NP complete, phylogenetic network, phylogeny, reconstruction, temporal-hybridization number, time consistent network, tree-child network. Note: https://arxiv.org/abs/1712.04127.
2017
9 Christopher Bryant, Mareike Fischer, Simone Linz and Charles Semple. On the Quirks of Maximum Parsimony and Likelihood on Phylogenetic Networks. In JTB, Vol. 417:100-108, 2017. Keywords: explicit network, from sequences, likelihood, parsimony, phylogenetic network, phylogeny. Note: http://arxiv.org/abs/1505.06898.         10 Magnus Bordewich, Simone Linz and Charles Semple. Lost in space? Generalising subtree prune and regraft to spaces of phylogenetic networks. In JTB, Vol. 423:1-12, 2017. Keywords: distance between networks, explicit network, phylogenetic network, phylogeny, reticulation-visible network, SPR distance, tree-based network, tree-child network. Note: https://simonelinz.files.wordpress.com/2017/04/bls171.pdf.
2016
11 Katharina Huber, Simone Linz, Vincent Moulton and Taoyang Wu. Spaces of phylogenetic networks from generalized nearest-neighbor interchange operations. In JOMB, Vol. 72(2):699-725, 2016. Keywords: bound, distance between networks, from network, LST distance, phylogenetic network, phylogeny.
2014
12 Paul Cordue, Simone Linz and Charles Semple. Phylogenetic Networks that Display a Tree Twice. In BMB, Vol. 76(10):2664-2679, 2014. Keywords: from rooted trees, normal network, phylogenetic network, phylogeny, reconstruction, tree-child network. Note: http://www.math.canterbury.ac.nz/~c.semple/papers/CLS14.pdf.         Toggle abstract "In the last decade, the use of phylogenetic networks to analyze the evolution of species whose past is likely to include reticulation events, such as horizontal gene transfer or hybridization, has gained popularity among evolutionary biologists. Nevertheless, the evolution of a particular gene can generally be described without reticulation events and therefore be represented by a phylogenetic tree. While this is not in contrast to each other, it places emphasis on the necessity of algorithms that analyze and summarize the tree-like information that is contained in a phylogenetic network. We contribute to the toolbox of such algorithms by investigating the question of whether or not a phylogenetic network embeds a tree twice and give a quadratic-time algorithm to solve this problem for a class of networks that is more general than tree-child networks. © 2014, Society for Mathematical Biology."
2013
13 Leo van Iersel and Simone Linz. A quadratic kernel for computing the hybridization number of multiple trees. In IPL, Vol. 113:318-323, 2013. Keywords: explicit network, FPT, from rooted trees, kernelization, minimum number, phylogenetic network, phylogeny, Program Clustistic, Program MaafB, Program PIRN, reconstruction. Note: http://arxiv.org/abs/1203.4067, poster.         Toggle abstract "It has recently been shown that the NP-hard problem of calculating the minimum number of hybridization events that is needed to explain a set of rooted binary phylogenetic trees by means of a hybridization network is fixed-parameter tractable if an instance of the problem consists of precisely two such trees. In this paper, we show that this problem remains fixed-parameter tractable for an arbitrarily large set of rooted binary phylogenetic trees. In particular, we present a quadratic kernel. © 2013 Elsevier B.V." 14 Peter J. Humphries, Simone Linz and Charles Semple. On the complexity of computing the temporal hybridization number for two phylogenies. In DAM, Vol. 161:871-880, 2013. Keywords: agreement forest, APX hard, characterization, from rooted trees, hybridization, NP complete, phylogenetic network, phylogeny, reconstruction, time consistent network. Note: http://ab.inf.uni-tuebingen.de/people/linz/publications/TAFapx.pdf.         Toggle abstract "Phylogenetic networks are now frequently used to explain the evolutionary history of a set of species for which a collection of gene trees, reconstructed from genetic material of different parts of the species' genomes, reveal inconsistencies. However, in the context of hybridization, the reconstructed networks are often not temporal. If a hybridization network is temporal, then it satisfies the time constraint of instantaneously occurring hybridization events; i.e. all species that are involved in such an event coexist in time. Furthermore, although a collection of phylogenetic trees can often be merged into a hybridization network that is temporal, many algorithms do not necessarily find such a network since their primary optimization objective is to minimize the number of hybridization events. In this paper, we present a characterization for when two rooted binary phylogenetic trees admit a temporal hybridization network. Furthermore, we show that the underlying optimization problem is APX-hard and, therefore, NP-hard. Thus, unless P=NP, it is unlikely that there are efficient algorithms for either computing an exact solution or approximating it within a ratio arbitrarily close to one. © 2012 Elsevier B.V. All rights reserved." 15 Simone Linz, Katherine St. John and Charles Semple. Counting trees in a phylogenetic network is #P-complete. In SICOMP, Vol. 42(4):1768-1776, 2013. Keywords: counting, from network, phylogenetic network, phylogeny. Note: http://ab.inf.uni-tuebingen.de/people/linz/publications/counting.pdf.         16 Simone Linz. Reticulation. In Brenner's Encyclopedia of Genetics (Second Edition), 2013. Keywords: phylogenetic network, phylogeny, survey.         17 Peter J. Humphries, Simone Linz and Charles Semple. Cherry picking: a characterization of the temporal hybridization number for a set of phylogenies. In BMB, Vol. 75(10):1879-1890, 2013. Keywords: characterization, cherry-picking, from rooted trees, hybridization, NP complete, phylogenetic network, phylogeny, reconstruction, time consistent network. Note: http://ab.inf.uni-tuebingen.de/people/linz/publications/CPSpaper.pdf.         Toggle abstract "Recently, we have shown that calculating the minimum-temporal-hybridization number for a set P of rooted binary phylogenetic trees is NP-hard and have characterized this minimum number when P consists of exactly two trees. In this paper, we give the first characterization of the problem for P being arbitrarily large. The characterization is in terms of cherries and the existence of a particular type of sequence. Furthermore, in an online appendix to the paper, we show that this new characterization can be used to show that computing the minimum-temporal hybridization number for two trees is fixed-parameter tractable. © 2013 Society for Mathematical Biology." 18 Steven Kelk, Simone Linz and David A. Morrison. Fighting network space: it is time for an SQL-type language to filter phylogenetic networks. 2013. Keywords: database, explicit network, from network, phylogenetic network, phylogeny. Note: http://arxiv.org/abs/1310.6844.
2012
19 Celine Scornavacca, Simone Linz and Benjamin Albrecht. A first step towards computing all hybridization networks for two rooted binary phylogenetic trees. In JCB, Vol. 19:1227-1242, 2012. Keywords: agreement forest, explicit network, FPT, from rooted trees, phylogenetic network, phylogeny, Program Dendroscope, Program Hybroscale, reconstruction. Note: http://arxiv.org/abs/1109.3268.         Toggle abstract "Recently, considerable effort has been put into developing fast algorithms to reconstruct a rooted phylogenetic network that explains two rooted phylogenetic trees and has a minimum number of hybridization vertices. With the standard app1235roach to tackle this problem being combinatorial, the reconstructed network is rarely unique. From a biological point of view, it is therefore of importance to not only compute one network, but all possible networks. In this article, we make a first step toward approaching this goal by presenting the first algorithm-called allMAAFs-that calculates all maximum-acyclic-agreement forests for two rooted binary phylogenetic trees on the same set of taxa. © Copyright 2012, Mary Ann Liebert, Inc. 2012." 20 Steven Kelk, Leo van Iersel, Nela Lekic, Simone Linz, Celine Scornavacca and Leen Stougie. Cycle killer... qu'est-ce que c'est? On the comparative approximability of hybridization number and directed feedback vertex set. In SIDMA, Vol. 26(4):1635-1656, 2012. Keywords: agreement forest, approximation, explicit network, from rooted trees, minimum number, phylogenetic network, phylogeny, Program CycleKiller, reconstruction. Note: http://arxiv.org/abs/1112.5359, about the title.         Toggle abstract "We show that the problem of computing the hybridization number of two rooted binary phylogenetic trees on the same set of taxa X has a constant factor polynomial-time approximation if and only if the problem of computing a minimum-size feedback vertex set in a directed graph (DFVS) has a constant factor polynomial-time approximation. The latter problem, which asks for a minimum number of vertices to be removed from a directed graph to transform it into a directed acyclic graph, is one of the problems in Karp's seminal 1972 list of 21 NP-complete problems. Despite considerable attention from the combinatorial optimization community, it remains to this day unknown whether a constant factor polynomial-time approximation exists for DFVS. Our result thus places the (in)approximability of hybridization number in a much broader complexity context, and as a consequence we obtain that it inherits inapproximability results from the problem Vertex Cover. On the positive side, we use results from the DFVS literature to give an O(log r log log r) approximation for the hybridization number where r is the correct value. Copyright © by SIAM."
2011
21 Josh Voorkamp né Collins, Simone Linz and Charles Semple. Quantifying hybridization in realistic time. In JCB, Vol. 18(10):1305-1318, 2011. Keywords: explicit network, FPT, from rooted trees, hybridization, minimum number, phylogenetic network, phylogeny, Program HybridInterleave, reconstruction, software. Note: http://wwwcsif.cs.ucdavis.edu/~linzs/CLS10_interleave.pdf, software available at http://www.math.canterbury.ac.nz/~c.semple/software.shtml.         Toggle abstract "Recently, numerous practical and theoretical studies in evolutionary biology aim at calculating the extent to which reticulation-for example, horizontal gene transfer, hybridization, or recombination-has influenced the evolution for a set of present-day species. It has been shown that inferring the minimum number of hybridization events that is needed to simultaneously explain the evolutionary history for a set of trees is an NP-hard and also fixed-parameter tractable problem. In this article, we give a new fixed-parameter algorithm for computing the minimum number of hybridization events for when two rooted binary phylogenetic trees are given. This newly developed algorithm is based on interleaving-a technique using repeated kernelization steps that are applied throughout the exhaustive search part of a fixed-parameter algorithm. To show that our algorithm runs efficiently to be applicable to a wide range of practical problem instances, we apply it to a grass data set and highlight the significant improvements in terms of running times in comparison to an algorithm that has previously been implemented. © 2011, Mary Ann Liebert, Inc."
2010
22 Simone Linz, Charles Semple and Tanja Stadler. Analyzing and reconstructing reticulation networks under timing constraints. In JOMB, Vol. 61(5):715-737, 2010. Keywords: explicit network, from rooted trees, hybridization, lateral gene transfer, NP complete, phylogenetic network, phylogeny, reconstruction, time consistent network. Note: http://dx.doi.org/10.1007/s00285-009-0319-y..         Toggle abstract "Reticulation networks are now frequently used to model the history of life for various groups of species whose evolutionary past is likely to include reticulation events such as horizontal gene transfer or hybridization. However, the reconstructed networks are rarely guaranteed to be temporal. If a reticulation network is temporal, then it satisfies the two biologically motivated timing constraints of instantaneously occurring reticulation events and successively occurring speciation events. On the other hand, if a reticulation network is not temporal, it is always possible to make it temporal by adding a number of additional unsampled or extinct taxa. In the first half of the paper, we show that deciding whether a given number of additional taxa is sufficient to transform a non-temporal reticulation network into a temporal one is an NP-complete problem. As one is often given a set of gene trees instead of a network in the context of hybridization, this motivates the second half of the paper which provides an algorithm, called TemporalHybrid, for reconstructing a temporal hybridization network that simultaneously explains the ancestral history of two trees or indicates that no such network exists. We further derive two methods to decide whether or not a temporal hybridization network exists for two given trees and illustrate one of the methods on a grass data set. © 2009 The Author(s)."
2009
23 Simone Linz and Charles Semple. Hybridization in non-binary trees. In TCBB, Vol. 6(1):30-45, 2009. Keywords: agreement forest, FPT, from rooted trees, hybridization, phylogenetic network, phylogeny, reconstruction. Note: http://www.math.canterbury.ac.nz/~c.semple/papers/LS08.pdf, slides available at http://www.newton.cam.ac.uk/webseminars/pg+ws/2007/plg/plgw03/1220/linz/.
2008
24 Simone Linz. Reticulation in evolution. PhD thesis, Heinrich-Heine-University, Düsseldorf, Germany, 2008. Keywords: agreement forest, FPT, from rooted trees, lateral gene transfer, phylogenetic network, phylogeny, SPR distance, statistical model. Note: http://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=8505.
2007
25 Magnus Bordewich, Simone Linz, Katherine St. John and Charles Semple. A reduction algorithm for computing the hybridization number of two trees. In EBIO, Vol. 3:86-98, 2007. Keywords: agreement forest, FPT, from rooted trees, hybridization, phylogenetic network, phylogeny, Program HybridNumber. Note: http://www.math.canterbury.ac.nz/~c.semple/papers/BLSS07.pdf.