Arendt J, Reznick D.. Convergence and parallelism reconsidered: what have we learned about the genetics of adaptation? Trends Ecol Evol 23: 26-32

Department of Biology, University of California - Riverside, 900 University Avenue, Riverside CA 92521, USA. <>
Trends in Ecology & Evolution (Impact Factor: 16.2). 02/2008; 23(1):26-32. DOI: 10.1016/j.tree.2007.09.011
Source: PubMed


Biologists often distinguish 'convergent' from 'parallel' evolution. This distinction usually assumes that when a given phenotype evolves, the underlying genetic mechanisms are different in distantly related species (convergent) but similar in closely related species (parallel). However, several examples show that the same phenotype might evolve among populations within a species by changes in different genes. Conversely, similar phenotypes might evolve in distantly related species by changes in the same gene. We thus argue that the distinction between 'convergent' and 'parallel' evolution is a false dichotomy, at best representing ends of a continuum. We can simplify our vocabulary; all instances of the independent evolution of a given phenotype can be described with a single term - convergent.

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    • "As a matter of fact, the character displacement hypothesis implies that allopatric populations of potential competitors may show convergence in niche requirements . If their parallel adaptation also lead to convergence in growth performance (approaching the same fitness peak on an adaptive landscape;Fong, Joyce &amp; Palsson 2005;Arendt &amp; Reznick 2008), they may become ecologically equivalent and, on secondary contacts, form 'neutral communities'. Here, we report an experiment that addresses how evolution of species in sympatry or allopatry affects both stabilizing and equalizing forces that determine coexistence in a microbial system. "

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    • "This requires an in-depth knowledge of their genetic basis. A recent upsurge of interest thus centres on the question of whether or not repeated instances of phenotypic evolution or adaptations to the same environment share the same genetic basis (Elmer & Meyer 2011; Stern & Orgogozo 2009; Arendt & Reznick 2007; Jones et al. 2012; Soria-Carrasco et al. 2014). To a certain extent, this seems to be the case, even though most studies pursuing this question employed a candidate gene approach (reviewed, e.g., in Stern 2013; Gompel & Prud&apos;homme 2009). "
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    • "The genetic basis of phenotypic novelty is a major unresolved question in evolutionary biology (Beldade and Brakefield 2002; Wray et al. 2003; Hahn et al. 2007; Arendt and Reznick 2008; Conant and Wolfe 2008; Stern and Orgogozo 2008). Understanding the processes that give rise to major phenotypic shifts has also generated considerable disagreement (Hoekstra and Coyne 2007; Mitchell-Olds et al. 2007; Halligan et al. 2013; Parker et al. 2014). "
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