Dynamic patterns of adaptive radiation.

Sergey Gavrilets; Aaron Vose

doi:10.1073/pnas.0506330102

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Dynamic patterns of adaptive radiation.

Sergey Gavrilets·Aaron Vose

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Abstract

Adaptive radiation is defined as the evolution of ecological and phenotypic diversity within a rapidly multiplying lineage. When it occurs, adaptive radiation typically follows the colonization of a new environment or the establishment of a "key innovation," which opens new ecological niches and/or new paths for evolution. Here, we take advantage of recent developments in speciation theory and modern computing power to build and explore a large-scale, stochastic, spatially explicit, individual-based model of adaptive radiation driven by adaptation to multidimensional ecological niches. We are able to model evolutionary dynamics of populations with hundreds of thousands of sexual diploid individuals over a time span of 100,000 generations assuming realistic mutation rates and allowing for genetic variation in a large number of both selected and neutral loci. Our results provide theoretical support and explanation for a number of empirical patterns including "area effect," "overshooting effect," and "least action effect," as well as for the idea of a "porous genome." Our findings suggest that the genetic architecture of traits involved in the most spectacular radiations might be rather simple. We show that a great majority of speciation events are concentrated early in the phylogeny. Our results emphasize the importance of ecological opportunity and genetic constraints in controlling the dynamics of adaptive radiation.

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Adaptation, Biological Computer Simulation Demography Environment Genetic Variation Genetics, Population Models, Theoretical Mutation Phylogeny Population Dynamics Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Sergey Gavrilets, Aaron Vose. 2005-12-05. Dynamic patterns of adaptive radiation.. https://doi.org/10.1073/pnas.0506330102

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