The evolution of locomotory behavior in profitable and unprofitable simulated prey

Area of Science:

• Evolutionary Biology
• Animal Behavior
• Predator-Prey Dynamics

Background:

• Unprofitable prey, such as those with noxious chemicals, often display slower, more predictable movement than profitable prey.
• Hypotheses suggest this may be due to reduced selection pressure for escape or active signaling of unprofitability.

Purpose of the Study:

• To empirically test hypotheses explaining movement differences between profitable and unprofitable prey.
• To investigate the role of predator avoidance and signaling in the evolution of prey locomotion.

Main Methods:

• Utilized a novel "artificial world" simulation with human selection over multiple generations.
• Manipulated locomotory characteristics (step size, waiting time, angular direction) of artificial prey.
• Varied prey recognizability and survival rates to simulate different ecological pressures.

Main Results:

• Unprofitable prey evolved significantly slower movement when easily recognized or when they frequently survived attacks.
• Slower movement in unprofitable prey was primarily driven by stronger selection on profitable prey to evade capture.
• Morphologically similar unprofitable prey evolved particularly slow movement, enhancing their recognition.

Conclusions:

• Provides empirical support for hypotheses explaining movement disparities between profitable and unprofitable prey.
• Demonstrates that locomotor mimicry by profitable prey is not guaranteed, even with morphological similarity.
• Highlights the adaptive significance of movement patterns in predator-prey interactions and defense strategies.