Genes as leaders and followers in evolution.
A major question for the study of phenotypic evolution is whether intra- and interspecific diversity originates directly from genetic variation, or instead, as plastic responses to environmental influences initially, followed later by genetic change. In species with discrete alternative phenotypes, evolutionary sequences can be inferred from transitions between environmental and genetic phenotype control, and from losses of phenotypic alternatives. From the available evidence, sequences appear equally probable to start with genetic polymorphism as with polyphenism, with a possible dominance of one or the other for specific trait types. We argue in this review that to evaluate the prevalence of each route, an investigation of both genetic and environmental cues for phenotype determination in several related rather than in isolated species is required.
Evolutionary Genetics, Centre for Ecological and Evolutionary Studies, University of Groningen, 9700 CC Groningen, The Netherlands. tanja.schwander@gmail.com
Tanja
T
Schwander
Olof
O
Leimar
D044822:Biodiversity; D005075:Biological Evolution; D009154:Mutation; D010641:Phenotype; D010802:Phylogeny; D011110:Polymorphism, Genetic; D013045:Species Specificity