Reconstruction of time-consistent species trees

Manuel Lafond; Marc Hellmuth

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arXiv · 1910.13123

Reconstruction of time-consistent species trees

Manuel Lafond·Marc Hellmuth

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Abstract

The history of gene families -- which are equivalent to event-labeled gene trees -- can to some extent be reconstructed from empirically estimated evolutionary event-relations containing pairs of orthologous, paralogous or xenologous genes. The question then arises as whether inferred event-labeled gene trees are "biologically feasible" which is the case if one can find a species tree with which the gene tree can be reconciled in a time-consistent way. In this contribution, we consider event-labeled gene trees that contain speciation, duplication as well as horizontal gene transfer and we assume that the species tree is unknown. We provide a cubic-time algorithm to decide whether a "time-consistent" binary species for a given event-labeled gene tree exists and, in the affirmative case, to construct the species tree within the same time-complexity.

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Manuel Lafond, Marc Hellmuth. 2019-10-29. Reconstruction of time-consistent species trees. https://arxiv.org/abs/1910.13123

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