Anti-predator behaviour changes following an aggressive encounter in the lizard Tropidurus hispidus

Area of Science:

• Behavioral Ecology
• Animal Behavior
• Evolutionary Biology

Background:

• Territorial defense can conflict with predator avoidance, as hiding residents cannot monitor or defend their territory.
• Persistent intruders may signal future intrusions, prompting territorial residents to prioritize minimizing intrusion costs, even at higher predation risks.

Purpose of the Study:

• To investigate how past and ongoing aggressive interactions influence anti-predator behavior in territorial lizards.
• To test the economic hypothesis predicting increased predation risk to minimize future territorial intrusion.

Main Methods:

• Experiments were conducted with male Tropidurus hispidus lizards.
• Key metrics recorded included approach distance to predators and time to re-emerge from refuge after hiding.
• Predation risk scenarios were manipulated relative to aggressive encounters.

Main Results:

• Lizards re-emerged sooner from refuge when a predator attacked 5 minutes after an aggressive encounter, compared to controls.
• Approach distance to predators was reduced when the predator attacked during an ongoing aggressive encounter.
• Results indicate lizards incur greater predation risks to minimize future territorial intrusion.

Conclusions:

• Tropidurus hispidus adjusts anti-predator behavior based on the immediacy and type of social interactions (past vs. ongoing aggression).
• Findings support an economic hypothesis balancing predation risk against territorial defense costs.
• Results inform studies on behavioral plasticity, social environment impacts, and the co-evolution of aggressive and anti-predator strategies.