Group chase and escape with prey's anti-attack behavior

Group chase and escape is widely observed in nature, where the predators approach the prey and the prey try to escape. An interesting phenomenon occurs when a prey group is under attack, whereby some individuals perform anti-attack behavior that places themselves at a greater risks of being caught. It remains unclear why certain prey would risk their survival and what conditions and internal mechanisms trigger this anti-attack response. Using a set of local interaction rules among prey and predators, we proposed a continuous-space and discrete-time model that incorporates energy level, variable speed and handling time by considering different aggregation preferences of prey. We found that anti-attack behavior contributes to enhance the survivability of the prey group and the effect is more efficient in the presence of aggregation preference. The survivability can be improved if the fleeing prey have no aggregation preference while the anti-attack prey use a general aggregation preference.