Evolution through genetically controlled allometry space.

Nicolas B Langlade; Xianzhong Feng; Tracy Dransfield; Lucy Copsey; Andrew I Hanna; Christophe Thébaud; Andrew Bangham; Andrew Hudson; Enrico Coen

doi:10.1073/pnas.0504210102

PubMed · 16009935

Evolution through genetically controlled allometry space.

Nicolas B Langlade·Xianzhong Feng·Tracy Dransfield·Lucy Copsey·Andrew I Hanna·Christophe Thébaud·Andrew Bangham·Andrew Hudson·Enrico Coen

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Abstract

Understanding evolutionary change requires phenotypic differences between organisms to be placed in a genetic context. However, there are few cases where it has been possible to define an appropriate genotypic space for a range of species. Here we address this problem by defining a genetically controlled space that captures variation in shape and size between closely related species of Antirrhinum. The axes of the space are based on an allometric model of leaves from an F2 of an interspecific cross between Antirrhinum majus and Antirrhinum charidemi. Three principal components were found to capture most of the genetic variation in shape and size, allowing a three-dimensional allometric space to be defined. The contribution of individual genetic loci was determined from QTL analysis, allowing each locus to be represented as a vector in the allometric space. Leaf shapes and sizes of 18 different Antirrhinum taxa, encompassing a broad range of leaf morphologies, could be accurately represented as clouds within the space. Most taxa overlapped with, or were near to, at least one other species in the space, so that together they defined a largely interconnected domain of viable forms. It is likely that the pattern of evolution within this domain reflects a combination of directional selection and evolutionary tradeoffs within a high dimensional space.

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Antirrhinum Biological Evolution Biometry Chromosome Mapping Genotype Hybridization, Genetic Lod Score Models, Biological Phenotype Plant Leaves Principal Component Analysis Quantitative Trait Loci Species Specificity Comparative Study Journal Article

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Nicolas B Langlade, Xianzhong Feng, Tracy Dransfield, Lucy Copsey, Andrew I Hanna, Christophe Thébaud, Andrew Bangham, Andrew Hudson, Enrico Coen. 2005-07-11. Evolution through genetically controlled allometry space.. https://doi.org/10.1073/pnas.0504210102

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