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Whole-mount Clearing and Staining of Arabidopsis Flower Organs and Siliques
Published on: April 12, 2018
Evolutionary paths underlying flower color variation in Antirrhinum
Annabel C Whibley1, Nicolas B Langlade, Christophe Andalo
1Department of Cell and Developmental Biology, John Innes Centre, Colney Lane, Norwich NR4 7UH, UK.
Science (New York, N.Y.)
|August 19, 2006
Summary
Flower color evolution in Antirrhinum is guided by a U-shaped genotypic path, allowing adaptation while avoiding low-fitness hybrids. This evolutionary trajectory explains steep genetic clines observed at hybrid zones.
Area of Science:
- Evolutionary biology
- Genetics
- Plant science
Background:
- Understanding evolutionary pathways is crucial for explaining biological diversity.
- Flower color variation in Antirrhinum (snapdragon) presents a model for studying evolutionary trajectories.
Purpose of the Study:
- To define and analyze the genotypic space governing flower color evolution in Antirrhinum.
- To investigate the evolutionary forces shaping hybrid zones between different flower color morphs.
Main Methods:
- Defined a three-dimensional genotypic space to map Antirrhinum flower color morphs.
- Analyzed genetic clines within a hybrid zone to identify loci under selection.
- Characterized the distribution of diverse Antirrhinum phenotypes within the genotypic space.
Main Results:
- A steep genetic cline was observed at genes controlling flower color, indicating selection.
- Antirrhinum species formed a U-shaped distribution in the genotypic space.
- Hybridization between distinct morphs resulted in low-fitness genotypes.
Conclusions:
- The U-shaped genotypic cloud represents a viable evolutionary path for flower color adaptation.
- This path facilitates evolution while circumventing less-adaptive genotypic regions.
- The model explains the steep clines at hybrid zones due to the fitness cost of hybridization between divergent lineages.
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