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Published on: May 13, 2016
Heterospecific aggression and adaptive divergence in brook stickleback (Culaea inconstans)
1Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada. kpeiman@uoguelph.ca
Summary
Brook stickleback evolved increased aggression towards ninespine stickleback when they coexist. This evolved aggression, along with pre-existing traits, structures stickleback communities.
Area of Science:
- Behavioral Ecology
- Evolutionary Biology
- Animal Behavior
Background:
- Agonistic behavior between species can lead to resource or habitat shifts.
- Aggression can evolve to exclude competitors from resources, mimicking ecological character displacement without exploitative competition.
Purpose of the Study:
- To determine if brook stickleback (Culaea inconstans) evolved heterospecific agonistic behavior towards ninespine stickleback (Pungitius pungitius).
- To assess the heritability of heterospecific aggressive behavior in brook stickleback.
Main Methods:
- Compared aggressive behavior in allopatric brook stickleback populations with sympatric populations coexisting with ninespine stickleback.
- Rearing family groups in a common environment to test for heritable variation in aggression.
Main Results:
- Allopatric brook stickleback were more aggressive than ninespine stickleback.
- Sympatric adult brook stickleback exhibited greater aggression towards ninespine stickleback compared to allopatric individuals.
- Heterospecific aggressive behaviors were found to be heritable.
- Aggression in juvenile brook stickleback increased with age in sympatric but not allopatric populations.
Conclusions:
- Brook stickleback have evolved increased aggression in response to coexistence with ninespine stickleback.
- Both evolved and pre-existing variation in brook stickleback aggression shape stickleback community structure.
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