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Updated: Jun 3, 2026
08:51
Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks
Published on: May 13, 2016
Cryptic genetic variation and body size evolution in threespine stickleback
Katrina McGuigan1, Nicole Nishimura, Mark Currey
1School of Biological Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia. k.mcguigan1@uq.edu.au
Evolution; International Journal of Organic Evolution
|April 6, 2011
Summary
Environmental conditions can unlock hidden genetic variation for body size evolution in threespine stickleback. This discovery sheds light on how populations adapt to new habitats.
Area of Science:
- Evolutionary Biology
- Ecology
- Genetics
Background:
- The environment acts as a selective force, driving evolutionary change.
- Environmental influence on the expression of genetic variation is less understood, especially in novel environments.
Purpose of the Study:
- To investigate how environmental conditions affect the evolvability of body size in threespine stickleback (Gasterosteus aculeatus).
- To understand the genetic basis of rapid size evolution in freshwater stickleback populations.
Main Methods:
- Rearing an oceanic stickleback population under high (ancestral) and low (freshwater colonization) salinity conditions.
- Assessing genetic variation for body size under different salinity treatments.
Main Results:
- Low genetic variation for body size was observed under high salinity.
- Significant increase in genetic variation for body size occurred under low salinity.
Conclusions:
- Oceanic stickleback populations possess standing genetic variation for body size.
- This genetic variation becomes accessible for selection only after colonization of new environments, such as freshwater habitats.
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