Understanding Courtship Behavior in Animals

1. Courtship behavior By G.Mallanagoud, Asst. Prof. Dept. of Zoology Veerashaiva College, Ballari, Karnataka.

2. COURTSHIP BEHAIVOUR Introduction: The term courtship refers to the behavioral interaction that takes place between the male and females before, during and just after the act of mating. Courtship: “The behavioral interaction that occurs between the males and females before, during and just after the act of mating is called courtship”. • According to the De Morries “ The courtship is defined as the heterosexual communication system leading to consummator sexual act.” • Behavioral process whereby adults of a species try to attract a potential mate. Courtship behaviors ensure that males and females of the same species recognize each other. Environmental stimuli i.e seasonal changes will stimulate courtship. Sensory cues (for example chemical odor cues, visual displays, sounds or color) will serve as courtship attractants in animals. • • •

3. o During courtship some animals may for a long time and they involves vigorous and elaborate displays. o Generally male plays an active role during courtship. o Usually first male initiates sexual interaction. Male displays the courtship behavior in front of the female whose behavior is either receptive or non-receptive. o Generally the male partner is involved to attract the opposite sex for mating purpose. o Several factors affect on sexual responsiveness of the mates. It may drop the courtship behavior if an enemy appears. It may also fall gradually if an animal suffering from diseases (illness). o Sexual responsiveness may disappear completely during winter season. o In evolutionary terms courtship provides chances for better survival. o The courtship performs four major functions. They are as follows. 1. Mate finding 2. Persuasion 3.Synchronization 4. Reproductive isolation

4. Principles of courtship behavior The courtship performs four major functions namely, mate finding, persuasion, synchronization and reproductive isolation. 1. Mate finding: o The mate finding (identify the opposite sexes for sexual intercourse) is the highly organized process. o It involves use of one or more senses to find out the opposite sexes. Such as sense of sight, smell, sound (Ex. frog), touch and even tastes. Generally it occurs in higher animals. o The vision (sense of sight) is the main factor for both animals. diurnal and nocturnal o The vision plays an important role in recognizing (identifying) a mate. Ex: In Owls and certain insects have special lenses which enable them to find a mate by straight light. o In fireflies and Deep Ocean animals have light producing organs (Bioluminescence), which help in mate finding. o In sea cows and whales, rarely on chemical traits for mate finding and on land scents (pheromones) are very important for sexual intercourse, because they bring attract the sex together. o In frog, the male is responsible to produce the croaking sound to attract the female for copulation during breeding season.

5. 2. Persuasion: o In some animals, meeting of male and female leads to mate (copulate) immediately. o Normally the male is more ready to mate with the female than the others. o Male performs certain behavioral patterns, which stimulate the female until she (female) becomes sexually receptive. o The female is more valuable than the male, because she carries the eggs after mating and also protects the young one (parental care). In addition, the male is usually capable of fertilizing more than one female. Therefore, the female requires some persuasion. Generally the males are actively involved in the courtship. Ex: In spider, the female attracts the male and eats him. o Male Salamander deposits a small jelly covered packages of sperms or spermatophores either on land or in water according to the habit of species. Then female comes and pick up one of the spermatophores with the help of cloaca. It is placed inside her body in a spermatheca, where the sperms remain to fertilize eggs. Thus internal fertilization occurs in Salamander. o Male Bull frog produce croaking call or sound by the vocal cords to attract the female for copulation. Probably the louder and longer calls are more attractive to females. As a result the ova and sperms are released simultaneously and external fertilization takes place in water.

6. In male Newt (Triturus) develops a large crest having black and red spots and an orange belly in the breading season. The male performs a dance to attract the female. If she (female) follows and touches his (male) tail with her snout, then the male deposits spermatophores, which are picked up by her cloaca. 3.Synchronization: “An Occurrence of the same behavior in different individuals (male and females of a species) at the same time is called synchronization”. o For successful synchronization both the sexes respond to the external cues. Such as day length, lunar cycle, presence of predator etc., o In marine forms, synchronization is related with the tides and phases of moon. 4. Reproductive isolation: o The courtship behavior plays an important role to ensures that animals mate only with their own species. o Courtship displays are highly species specific. o The signals used for attraction, persuasion, appeasement and synchronization. Ex: In most of the frogs, male produce croaking calls (mating call), which are species specific in terms of their pitch and timing. Female frogs approaches (responds) only to the calls of their own species. In Antennae of many male moths selectively respond to the odor emitted by the females of their own species. As a result, hybridization between two species is extremely rare.

7. Courtship and mating in Animals • Courtship and mating in Scorpions: In Scorpions the male not only stimulates the female sexually but, it has to suppress the non-sexual behavior of the female, so that she may not eat him. In scorpions, the courtship done in the form of a dance called ‘promenades a dues’ on finding a suitable mate. The two scorpions stand face to face with their tails, upraised and move about in circles. In some other species like male Rock scorpion, the male seizes the female with his pedipalps and together they walk background and forward. The courtship behavior may last from10 minutes to hours depending on how long it takes to locate a suitable site for spermatophore deposition. i.e ferm surface. A wing like lever extends from the spermatophore. The male then maneuvers the female, so the genital area is over the spermatophore. Pressure on the lever of spermatophyte releases the sperm mass, which is taken up into the female orifice. Thus in scorpions, coitus does not occur. • • • • • • Fig: Courtship behavior in scorpions

8. Courtship in Tilapia: Different species of fishes display diverse courtship patterns. Tilapia melanotherm display four ‘pure’ courtship patterns. Such as follows. • Nod : (Rapid titling down and forward) • Quiver : (A pattern of head shaking) • Nib: (biting the substrate) • Skim : (Remaining motionless near the nest) In Guppies, the courtship is the adaptation of a sigmoid or S-shaped posture by the male. Fig: Courtship behavior in Tilapia

9. Courtship in Frog: • During their breeding season (June to September) the frog becomes lightly excited. Hormones are carried by the blood from the interstitial cell of the testes throughout the body and bring about many changes in male frog. i.e colour and brightness of the skin which has its counterpart in the female. Thus on both sides there is some degree of emotional excitement. • The male frog begins to croak. The function of this croaking seems to be simply that of recognition between the sexes. produces advertisement calls by their vocal cords i.e they produce croaking sound to attract the females for copulation. During breeding season male frog • As a result, the female frogs moves towards the male and copulation takes place. Usually the louder and longer calls are attracted by the females. But in past croaking is also an advertisement of the breeding grounds. Fig: Courtship behavior in Frogs.

10. Courtship in Reptiles: During breeding season, most of the reptiles exhibits well courtship behavior. • Males of certain lizards fight and display either to terrify each other to evoke a suitable response from the female. • The male American Chameleon (Anolis carolinesis) displays a rhythmical up and down, bobbing of his body to show his dewlap, which is a bright red spot beneath the skin. • As the female approaches the male, the latter twists his tail around the female and inserts his hemi penis, but also to suppress her non-sexual behavior. • In this way make establishes his identify as a mate and makes necessary arrangements to remove temporarily the carnivorous instinct of female before he approaches her. Fig: Courtship behavior in Lizards and Chameleon

11. Courtship in Birds Courtship in Jacana: o The nest is built with the help of beak by using loose plant debris, it rests or floats on the water. o The female pushes the eggs together under his belly with the help of wings. o So that they lie warm and protected between his breast and underside of his wings. o Most Jacana species exhibit polyandry and “sex role reversal”. Males maintain small territories. Males perform all parental care. o Females mate with multiple males and then leave eggs with males. The number of males and female mates determines her reproductive success because she doesn’t care for eggs. Fig: Mating dance and other courtship behavior in Jacana Sexual dimorphism: Females larger than males. Both the sexes are having the same coloration. Females aggressively fight other females and also their chicks (infanticide).

12. Courtship behavior in Spotted Dove: o The scientific name of the spotted dove is Streptopelia chinensis. o The courtship behavior is characterized by the bowing of the male, in which the body is held parallel to the ground, the tail lifted vertically and fanned out. Fig: Courtship behavior in Spotted Dove:

13. Courtship behavior in birds of Paradise: o Males are the most conspicuously decorated birds; parts of their plumage are reminiscent of silk or velvet or have a metallic glass. o They almost always have extremely varieties of colors and often prolonged decorative plumes of various types. Their son is of only moderate quality, some species are sound imitators. i.e They imitate the sound of others. o Most of them display in trees, but a few species display in a dancing area on the ground. Nests are usually cup-shaped structure. o Aru Island greater bird of paradise is introduced by loud calls of the males before the first rays of the rising sun have reached the branches of the trees. Some times it is repeated in the evening. Fig: Courtship behavior in Paradise birds

14. Courtship behavior in House Sparrows: o The mating habits or courtship behavior of the House Sparrow takes between January to july. o The males claim their nest sites and defend its immediate territory. o There is no defined area outside the nest that the bird defends. The male chirps by the nest site trying to attract a female. When a female comes by the male chirps louder and more quickly. o Sometimes the male will follow the female a short distance and hop or wing quiver around her if she passes by him. o Other males may join trying to attract the same female. Mating occurs throughout the breeding period (March to August) near the nest site and may occur several times during the day. o Once the birds become pair, nesting begins. These birds are monogamous. Although last mates are quickly replaced during the breeding season. Fig: Courtship behavior in House Sparrows

15. Courtship behavior in Peacocks: o During breeding season the male peacock gives colorful and impressive signal to the female for mating. One of the most striking features of a peacock’s tail is that some of the feathers end in an apparent eye-spot. o The eye-spots are spread over the tail but the number of eye-spots varies from male to male. o They advertise their presence by calling, their call being a harsh, unhealthy cry. Females visit the males at their display sites and select and mate with the male Peacock. o The female lays about 10 eggs and she is responsible for their incubation. o A large number of eye-spots indicate a large tail and probably an older male he will be a good mate because he is healthy and a good survivor. o The tail might attract predators, thus they only display to females. Usually the female is busy eating or minding her own business when a male comes over to her and starts fanning his tail and dancing around her. o It can seem very pushy and desperate especially when the female ignores him. Fig: Courtship behavior in Peacock

16. Courtship behavior in pigeons: o A male Pigeon puffs out his neck feathers, lowers his head and turns around in circles. o A male spreads his tail and drags it while running after a female. A male pigeon runs closely behind a female to move her away from other males. o A female puts her beak inside the male’s beak. Male Pigeon stands on top of a female and flaps his wings to keep his balance. o After mating, a male pigeon may make a display flight. In this display, the male ‘claps’ his wings twice. They are monogamous, often breeding in consecutive seasons for as long as both birds of a pair live. Fig: Courtship behavior in Pigeons

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