Sympatric speciation in structureless environments

BMC Evolutionary Biology

Research Article

Richard Salter¹  Dana Paige Seidel²  Wayne M. Getz³  Pim van Hooft⁴ 

[1] Computer Science Department, Oberlin College, 44074, Oberlin, OH, USA;Department ESPM, University of California, 94720-3114, Berkeley, CA, USA;Department ESPM, University of California, 94720-3114, Berkeley, CA, USA;School of Mathematical Sciences, University of KwaZulu-Natal, PB X54001, 4000, Durban, South Africa;Resource Ecology Group, Wageningen University, Droevendaalsesteeg 3a, 6708 PB, Wageningen, The Netherlands;

关键词: Magic traits;    Foraging guilds;    Disruptive selection;    Genetic algorithms;    Agent-based models;   

DOI  :  10.1186/s12862-016-0617-0

 received in 2015-12-02, accepted in 2016-02-12,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundDarwin and the architects of the Modern Synthesis found sympatric speciation difficult to explain and suggested it is unlikely to occur. Increasingly, evidence over the past few decades suggest that sympatric speciation can occur under ecological conditions that require at most intraspecific competition for a structured resource. Here we used an individual-based population model with variable foraging strategies to study the evolution of mating behavior among foraging strategy types. Initially, individuals were placed at random on a structureless resource landscape, with subsequent spatial variation induced through foraging activity itself. The fitness of individuals was determined by their biomass at the end of each generational cycle. The model incorporates three diallelic, codominant foraging strategy genes, and one mate-choice or m-trait (i.e. incipient magic trait) gene, where the latter is inactive when random mating is assumed.ResultsUnder non-random mating, the m-trait gene promotes increasing levels of either disassortative or assortative mating when the frequency of m respectively increases or decreases from 0.5. Our evolutionary simulations demonstrate that, under initial random mating conditions, an activated m-trait gene evolves to promote assortative mating because the system, in trying to fit a multipeak adaptive landscape, causes heterozygous individuals to be less fit than homozygous individuals.ConclusionOur results extend our theoretical understanding that sympatric speciation can evolve under nicheless or gradientless resource conditions: i.e. the underlying resource is monomorphic and initially spatially homogeneous. Further the simplicity and generality of our model suggests that sympatric speciation may be more likely than previously thought to occur in mobile, sexually-reproducing organisms.

【 授权许可】

CC BY   
© Getz et al. 2016

【 图 表 】

Fig. 1