Courtship display

These behaviors often include ritualized movement ("dances"), vocalizations, mechanical sound production, or displays of beauty, strength, or agonistic ability.

[9] When conducting a dive display, the male typically ascends approximately 20–35 m (66–115 ft) in the air then abruptly turns and descends in a dive-like fashion.

As the male flies over the female, he rotates his body and spreads his tail feathers, which flutter and collide to produce a short, buzzing sound.

This technique can be seen in the satin bowerbird (Ptilonorhynchus violaceus) of Australia, males of which build and decorate nest-like structures called "bowers".

[19][20] Such energy costs can include the effort associated in obtaining nuptial gifts for the female[21] or performing long courtship or copulatory behaviors.

In this case, the female of a species developed a sexually selected signal which serves a dual function of being both attractive to mates and deterring rivals.

Many anuran amphibians, such as the green tree frog, may use visual cues as well as auditory signals to increase their chances of impressing a mate.

[25] When the calls of the tree frogs were held equal, it was determined that females tended to overlook an auditory-only stimulus in favor of males who combined auditory/visual multi-modal signals.

During courtship, male peacock spiders compete using both visual displays and vibratory signals for intersexual communication.

In dance flies (Rhamphomyia longicauda), females have two ornaments — inflatable abdominal sacs and pinnate tibial scales — that they use as courtship displays in mating swarms.

With many socially monogamous species such as birds, their duet facilitates pre-copulatory reassurance of pair bonding and strengthens post-copulatory dedication to the development of offspring (e.g., great crested grebe, Podiceps cristatus).

[33] For example, male and female crested auklets, Aethia cristatella, will cackle at one another as a vocal form of mutual display that serves to strengthen a bond between the two.

[34] In some cases, males may pair up to perform mutual, cooperative displays in order to increase courtship success and attract females.

[38] Sexual ornaments can serve to increase attractiveness[39] and indicate good genes and higher levels of fitness.

For example, female canaries have been shown to produce larger and denser eggs in response to male supranormal song production.

The chemicals kill off older sperm from any previous mates, up-regulates the female's egg-laying rate, and reduces her desire to re-mate with another male.

[48] Even though this claw developed as a weapon, it is also closely linked with the crabs' courtship display: it is waved in a certain pattern to attract females for mating.

[53] This courtship period, which involves displays to attract a mate by a member of a species, is usually short, lasting anywhere from 15 minutes to a few days.

Emperor penguins engage in an extended courtship period that can last up to two months, the longest of any Arctic seabird.

[56] Under laboratory settings, courtship behaviours in this species, although complex and involving the release of pheromones,[57] represent as little as approximately one per cent of its daily calorie intake.

[56] In contrast, species that engage in prolonged or elaborate displays expend considerable amounts of energy and run the risk of developing fatigue.

During the peak of their breeding season, which lasts up to three months during spring,[58] leks are frequently visited by groups of up to seventy females.

[59] In response to such a large presence of females, males engage in a strutting display up to six to ten times per minute[60][61] for approximately three to four hours per day.

[54] In guppies (Poecilia reticulata), variation in the light environment plays a huge role in their ability to attract mates.

[62] Guppy males alter both their 'courtship mode', whether they perform a full courtship display or try to 'engage' in sneak copulations, and distance from females as light intensity changes.

[66] There are multiple hypotheses about how courtship displays may have evolved in animals, including the Fisherian runaway model and the good genes hypothesis.

However, as time goes on and generations pass, the survival advantage associated with one trait may dissipate due to extreme exaggeration to the point that it decreases fitness.

Only males with good genes are able to support a large investment into the development of such traits, which, in turn displays their high fitness.