Deception in animals

At the third level, the deceptive behaviour is at least partially learnt, as when a bird puts on a distraction display, feigning injury to lure a predator away from a nest.

Some types of deception in animals are completely involuntary (e.g. disruptive coloration), but others are under voluntary control and may involve an element of learning.

Most instances of voluntary deception in animals involve a simple behaviour, such as a cat arching its back and raising its hackles, to make itself appear larger than normal when attacked.

[6] Newly moulted mantis shrimps frequently deceive competitors in this way, even though their still-soft exoskeletons mean that they could not fight without damaging themselves.

[8] Anglerfish have a long filament (the illicium) sprouting from the middle of the head above the eyes and terminating in an irregular growth of flesh (the esca).

These are large dark markings that help prey escape by causing predators to attack a false target.

[11] Camouflage is the use of any combination of materials, coloration, or behaviour that helps to conceal an animal by making it hard to see (crypsis) or by disguising it as something else (mimesis).

These include, resemblance to the surroundings, disruptive coloration, eliminating shadow, self-decoration, cryptic behaviour, motion camouflage, changeable skin appearance, countershading, counter-illumination, transparency, and silvering to reflect the environment.

Similarly, the katydids, a group of grasshopper-like insects found worldwide, are nocturnal and use their cryptic colouration to remain unnoticed during the day.

A wide range of animals, e.g. lizards, birds, rodents, and sharks, behave as if dead as an anti-predator adaptation, as predators usually take only live prey.

[15] Birds often feign death to escape predation; for example tonic immobility in quail reduces the probability of attacks by cats.

[24] The philosopher Kristina Šekrst[4] uses the findings to show that if this is held to involve self-deception, then belief is implied to be present, meaning at least Mitchell's third level of deception.

The evolutionary ecologist Michael Angilletta et al. show that to establish adaptive self-deception, biologists must quantify the cost and benefit of ignoring one's true competitive ability.

[4] Tactical or functional deception is the use of signals or displays from an animal's normal repertoire to mislead or deceive another individual.