Advertising elusiveness

Elusiveness signals are given by prey during the close approach of a predator, acting to inform the predator that the prey would be difficult to catch and subdue, and, therefore, that an attempt to catch the prey is likely to be unsuccessful. These signals will be restricted to mobile prey that can mount an active response to impending attack and they will not normally be displayed continuously, but instead be triggered by the perception by the prey that they are under imminent risk of attack. There are two different types of such elusiveness signals: 1) pursuit deterrent signals, communicating fleetness or strength to coursing predators, and 2) perception advertisement, communicating detection of a stalking or ambushing predator. Elusiveness signals can only be effective if mounting attacks is expensive to predators in some way. There is also an element of generalization required for elusiveness signals to be effective but, by signalling fleetness, strength, or awareness of the predator, the prey also seek to differentiate themselves from other potential prey. We first document current empirical evidence for elusiveness signalling, before discussing evolutionary considerations—starting with theory on how such signalling might evolve and be maintained—ecological aspects, and co-evolutionary considerations.