Identifying species network features from gene tree quartets under the coalescent model

Hector Baños

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arXiv · 1711.10545

Identifying species network features from gene tree quartets under the coalescent model

Hector Baños

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Abstract

We show that many topological features of level-1 species networks are identifiable from the distribution of the gene tree quartets under the network multi-species coalescent model. In particular, every cycle of size at least 4 and every hybrid node in a cycle of size at least 5 is identifiable. This is a step toward justifying the inference of such networks which was recently implemented by Solís-Lemus and Ané. We show additionally how to compute quartet concordance factors for a network in terms of simpler networks, and explore some circumstances in which cycles of size 3 and hybrid nodes in 4-cycles can be detected.

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Hector Baños. 2017-11-28. Identifying species network features from gene tree quartets under the coalescent model. https://arxiv.org/abs/1711.10545

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