Display (zoology)

Communication is very important for animals all throughout the animal kingdom, even those with fairly simple nervous systems and body plans. For example, since female praying mantids are sexually cannibalistic, the male will typically avail of a concealment form of display behaviour.[2] This is a series of creeping movements executed by the male as it approaches the female with freezing of the body whenever the female looks towards the male. However, according to laboratory studies conducted by Loxton in 1979, one type of praying mantis, Ephestiasula arnoena, shows both male and female counterparts performing overt and ritualized behaviour before mating.[2] Both displayed a semaphore behaviour, meaning both displayed their front legs in a boxing fashion before the slow approach of the male from behind.[2] This semaphore display in E. arnoenaiskey in communicating between both mantids that both are ready for copulation and, by extension, the continuance of their genetic line.

Along with the display behaviour shown by the praying mantid, flies belonging to the genus Megaselia also show such behaviour.[4] Contrary to the typically female-selected mating that occurs for most organisms, these flies have females that show the display behaviour and males that choose the mate. Females have a bright orange colouring that attracts the male and also perform a series of fluttering wing movements that make the insect appear to "dance" and make the openings on their abdomens to swell in order to attract a male.[4] It is also interesting to note that there is experimental evidence that implies the female may also release pheromones that attract the male; this is an instance of chemical display behaviour that plays a large role in animal communication.[5]

This auditory courtship behavior is also seen in fruit flies like A. suspensa when they perform calling and pre-copulatory songs before mating. Both of these sounds are created by rapid flapping of the males wings.[6]

Many arachnids show ritualized displays. For example, the family Salticidae consists of jumping spiders with keen vision which results in very clear display behaviours for courting in particular.[1] Salticids are very similar in appearance to ants that live in the same area and therefore use their appearance to avoid predators. Since this similarity in appearance is so obvious, salticid spiders can use display behaviours to communicate both with members of their own species and also with members of the ants that they mimic.[1]

Birds also very commonly use display behaviours for courtship and communication. Manakin birds (in the family Pipridae) in the Amazon undergo large demonstrations of display behaviour in order to court females in the population.[7] Since males provide no other immediate benefit to females, they must undergo ritualized behaviours in order to show their fitness to possible mates; the female then uses the information she gathers from this interaction to make a decision on who she will mate with.[7] This display behaviour consists of various flight patterns, wing and colour displays, and particular vocalizations.[7] As a result of this performance, the males will be chosen by the female and reproduction will commence.

Along with invertebrates and birds, vertebrates like the harbour seal also show display behaviour. Since the harbour seal resides in an aquatic environment, the display behaviours expressed are slightly different from those seen in terrestrial mammal species. Male harbour seals show specific vocalization and diving behaviours while demonstrating such behaviours for possible mates.[3] As seals are distributed over such a large area, these display behaviours can slightly change geographically as males try to appeal to the largest number of females possible over a large geographical range. Dive displays, head flicks, and various vocalizations all work together in a display behaviour that signifies to the females in a colony that the males are ready to mate.[3]