Trait evolution with jumps: illusionary normality

Krzysztof Bartoszek

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arXiv · 1709.04702

Trait evolution with jumps: illusionary normality

Krzysztof Bartoszek

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Abstract

Phylogenetic comparative methods for real-valued traits usually make use of stochastic process whose trajectories are continuous. This is despite biological intuition that evolution is rather punctuated than gradual. On the other hand, there has been a number of recent proposals of evolutionary models with jump components. However, as we are only beginning to understand the behaviour of branching Ornstein-Uhlenbeck (OU) processes the asymptotics of branching OU processes with jumps is an even greater unknown. In this work we build up on a previous study concerning OU with jumps evolution on a pure birth tree. We introduce an extinction component and explore via simulations, its effects on the weak convergence of such a process. We furthermore, also use this work to illustrate the simulation and graphic generation possibilities of the mvSLOUCH package.

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Krzysztof Bartoszek. 2017-09-14. Trait evolution with jumps: illusionary normality. https://arxiv.org/abs/1709.04702

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