Figure 2.

Flexibility of Escape Execution in Different Species.Escape directionality depends on the presence and location of shelter (left panels). (Top) When an animal has knowledge that a refuge is inaccessible, absent, or too far away, the predominant response to threat switches from escape to freezing behaviour. (Bottom) The presence of a suitable refuge in the environment guides precise escape trajectories to its location. If a refuge becomes unavailable and the animal finds a new one, flight paths are modified accordingly very rapidly. Escape trajectories are threat-dependent (middle panels). (Top) The type and location of a predator influences escape trajectory. A frog directs its escape away from a terrestrial predator such as a snake, but flees towards an aerial predator such as a bat to undercut their flight path [117]. (Bottom) Animals including birds, deer, fish, and frogs flee directly away from threatening stimuli, which may function to maximize the distance between predator and prey. The same animals can also escape at a 130–90° angle, for example, to facilitate visual monitoring of predators during escape in response to less threatening stimuli, or as a less predictable, evasive manoeuvre in response to a fast predatory strike [118]. The physical and social environment modulates escape (right panels). (Top) Flight trajectories take into account the presence of obstacles in the environment. For example, fish that usually flee away from an approaching predator may escape towards it if an obstacle occludes the optimal escape path. (Bottom) Solitary fish can initiate escapes at various onset angles, whereas schooling fish escape in straight and uniform trajectories owing to the spatial constraints imposed by the shoal.