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arXiv · 1209.1494

Time to a single hybridization event in a group of species with unknown ancestral history

Krzysztof Bartoszek·Graham Jones·Bengt Oxelman·Serik Sagitov
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Abstract

We consider a stochastic process for the generation of species which combines a Yule process with a simple model for hybridization between pairs of co-existent species. We assume that the origin of the process, when there was one species, occurred at an unknown time in the past, and we condition the process on producing n species via the Yule process and a single hybridization event. We prove results about the distribution of the time of the hybridization event. In particular we calculate a formula for all moments, and show that under various conditions, the distribution tends to an exponential with rate twice that of the birth rate for the Yule process.

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Krzysztof Bartoszek, Graham Jones, Bengt Oxelman, Serik Sagitov. 2012-09-10. Time to a single hybridization event in a group of species with unknown ancestral history. https://arxiv.org/abs/1209.1494

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