Sex Differences in How Territory Quality Affects Aggression in Convict Cichlids

Area of Science:

• Ethology
• Behavioral Ecology
• Animal Communication

Background:

• Resource value significantly impacts aggression in animal contests.
• Territorial species adjust defense investment based on territory quality.
• Understanding sex-specific responses to resource value is crucial in behavioral ecology.

Purpose of the Study:

• To investigate the effect of territory quality on territorial aggression in convict cichlids (Amatitlania nigrofasciata).
• To examine sex differences in aggressive behaviors in relation to territory value.
• To determine if territory quality modulates aggression differently between males and females.

Main Methods:

• Male and female convict cichlids were assigned to territories of low, medium, or high resource value.
• Territories varied in substrate, nest site availability, and food resources.
• Aggressive behaviors (displays, bites, chases) were recorded after intruder introduction.

Main Results:

• Territory quality affected low-intensity aggression (displays) but not high-intensity aggression (bites, chases).
• Significant sex differences in aggression were observed, with females exhibiting more low-intensity behaviors.
• A sex-by-territory quality interaction showed females increasing high-intensity aggression with higher territory value.

Conclusions:

• Territory quality influences specific aggressive behaviors, but not all types of aggression.
• Females appear more sensitive to territory quality, potentially linked to nesting requirements.
• Sex plays a critical role in modulating the relationship between territory value and aggression.