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Updated: Jun 2, 2026
08:51
Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks
Published on: May 13, 2016
Quantitative genetic variation in static allometry in the threespine stickleback
Katrina McGuigan1, Nicole Nishimura, Mark Currey
1Centre for Ecology and Evolution, University of Oregon, Eugene, OR 97403, USA. k.mcguigan1@uq.edu.au
Integrative and Comparative Biology
|May 12, 2011
Summary
Genetic variation in body shape allometry influences evolutionary patterns in threespine stickleback. Additive genetic variance in size and size-independent shape, but not slopes, suggests allometry doesn't solely drive parallel evolution.
Area of Science:
- Evolutionary Biology
- Quantitative Genetics
- Ecology and Evolution
Background:
- Replicated evolution suggests consistent selection, but genetic variation also shapes phenotypes.
- Allometry (shape-size relationship) is a poorly understood source of genetic bias in evolution.
- Threespine stickleback (Gasterosteus aculeatus) populations show parallel freshwater evolution from marine ancestors.
Purpose of the Study:
- To investigate the role of genetic variation in body shape allometry in threespine stickleback evolution.
- To determine if additive genetic variation in allometric functions contributes to parallel phenotypic evolution.
- To assess if selection on body size or shape is a correlated response.
Main Methods:
- Laboratory-reared cohort from an oceanic Alaskan stickleback population.
- Determination of phenotypic static allometry for body shape and size.
- Estimation of additive genetic variation in allometric functions (slopes and elevation).
Main Results:
- Significant allometry detected: larger fish had smaller heads, longer dorsal fin bases, and longer, shallower caudal peduncles.
- Additive genetic variance found in body size and size-independent shape (allometric elevation).
- Little to no additive genetic variance found in allometric slopes.
Conclusions:
- Parallel body shape evolution in stickleback is unlikely a correlated response to selection on size, or vice versa.
- Allometry's influence on phenotypic evolution requires further study of genetic variation in allometric functions.
- Understanding genetic variance in allometry is crucial for explaining evolutionary patterns.
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