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Abstract BackgroundAggression is observed across the animal kingdom, and benefits animals in a number of ways to increase fitness and promote survival. While aggressive behaviors vary widely across populations and can evolve as an adaptation to a particular environment, the complexity of aggressive behaviors presents a challenge to studying the evolution of aggression. The Mexican tetra,Astyanax mexicanusexists as an aggressive river-dwelling surface form and multiple populations of a blind cave form, some of which exhibit reduced aggression, providing the opportunity to investigate how evolution shapes aggressive behaviors. ResultsTo define how aggressive behaviors evolve, we performed a high-resolution analysis of multiple social behaviors that occur during aggressive interactions inA. mexicanus.We found that many of the aggression-associated behaviors observed in surface-surface aggressive encounters were reduced or lost in Pachón cavefish. Interestingly, one behavior, circling, was observed more often in cavefish, suggesting evolution of a shift in the types of social behaviors exhibited by cavefish. Further, detailed analysis revealed substantive differences in aggression-related sub-behaviors in independently evolved cavefish populations, suggesting independent evolution of reduced aggression between cave populations. We found that many aggressive behaviors are still present when surface fish fight in the dark, suggesting that these reductions in aggression-associated and escape-associated behaviors in cavefish are likely independent of loss of vision in this species. Further, levels of aggression within populations were largely independent of type of opponent (cave vs. surface) or individual stress levels, measured through quantifying stress-like behaviors, suggesting these behaviors are hardwired and not reflective of population-specific changes in other cave-evolved traits. ConclusionThese results reveal that loss of aggression in cavefish evolved through the loss of multiple aggression-associated behaviors and raise the possibility that independent genetic mechanisms underlie changes in each behavior within populations and across populations. Taken together, these findings reveal the complexity of evolution of social behaviors and establishA. mexicanusas a model for investigating the evolutionary and genetic basis of aggressive behavior.
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Aggressive behavior across ant lineages: importance, quantification, and associations with trait evolution
Aggressive behavior, or lack thereof, is vital to the success of a social insect colony. A diversity of aggressive behaviors are exhibited in varying degrees by workers across ant species. To better understand this suite of behaviors, we review the extensive literature around ant aggression in order to assess the importance of aggression to the success of ant lineages, the ways in which aggression has been quantified in the literature, and potential correlations between aggression and other key functional traits. Our new contributions to this body of literature include an interaction framework for contextualizing the variation of behaviors, a new suggested scale for quantifying aggressive behaviors, and finally an investigation into traits that are correlated with aggression across ant lineages. Based on our phylogenetic comparative analyses, we find a negative correlation between eye length and aggression and that body size, worker polymorphism, and potentially participation in mutualisms with plants and other insects are evolutionarily linked to an increase in aggressive behavior.
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- Award ID(s):
- 2210800
- PAR ID:
- 10567239
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Insectes Sociaux
- Volume:
- 70
- Issue:
- 4
- ISSN:
- 0020-1812
- Page Range / eLocation ID:
- 393 to 403
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s00040-023-00931-6
