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Updated: Oct 5, 2025
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Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks
Published on: May 13, 2016
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Evolution of static allometry and constraint on evolutionary allometry in a fossil stickleback
Kjetil L Voje1, Michael A Bell2, Yoel E Stuart3
1Natural History Museum, University of Oslo, Oslo, Norway.
Journal of Evolutionary Biology
|January 24, 2022
Summary
Allometric scaling, the relationship between trait and body size, can evolve. In stickleback fish, armor traits evolved independently of body size, while non-armor traits remained constrained by allometry.
Area of Science:
- Evolutionary biology
- Paleontology
- Quantitative genetics
Background:
- Allometric scaling describes how trait size relates to body size, typically showing invariance due to developmental and selective constraints.
- Understanding the evolution of allometric relationships is crucial for explaining phenotypic diversification.
Purpose of the Study:
- To investigate the evolvability of static allometric slopes in a fossil lineage of Threespine Stickleback (Gasterosteus doryssus).
- To determine if allometric relationships constrain or facilitate evolutionary trajectories of traits over time.
Main Methods:
- Analyzed nine traits (five armor, four non-armor) in fossil Threespine Stickleback over 8500 years.
- Examined static allometric slopes and their relationship to evolutionary changes in trait means.
Main Results:
- Armor traits exhibited weak allometry and evolved independently of body size, suggesting constraints were overcome.
- Non-armor traits showed stronger allometric relationships that evolved slightly but remained predictive of evolutionary trajectories, supporting allometry as a constraint.
- Evolutionary allometry, where slopes predict trait evolution, was supported for non-armor traits.
Conclusions:
- Allometric relationships can evolve, but their strength and influence vary among traits.
- While some traits can escape allometric constraints through strong selection, others remain constrained, guiding evolutionary paths.
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