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Territoriality: Many species of butterflies maintain a clear-cut territory which is essentially a strategy to ensure greater chances of success in the search for partner, food as well as protection. In territorial behaviour, the dominant male termed as the ‘Holder’, will perch on a vantage point and patrol the area by flying through the habitat in search of receptive females as well as food. It will chase away any intruder which is generally a member of the same sex and species. When a suitable female is sighted, courting normally begins. Hilltopping is another form of territorial behaviour observed in butterfly species inhabiting mountains. In such species, males perch on hill-tops awaiting the arrival of receptive females. It will mate with the virgin females flying in to these areas. After mating, the female will subsequently leave the area searching for larval host plants for egg laying. Males will remain in the perching sites for most of their life and leave only periodically to visit nectar sources (Mathew 2011).

Perching/ Patrolling: The ways to locate mates vary greatly between species, but there are also examples of animals where the mate locating strategy varies within species (Krebs & Davies 1993; Andersson 1994). In species where the competition between males is strong and the ability to acquire matings is limited, males that lose contests with dominant opponents have to adopt a suboptimal strategy to acquire matings. Among insects subordinate males often adopt the role of a satellite in the vicinity of a dominant male and acquire matings by intercepting females on their way to a territory owner (Otte 1972; Cade 1980; Alcock 2005).

Courtship: The courtship of butterflies involves a variety of behavioural, physiological and biochemical mechanisms. A male butterfly actively searches for the female, using visual and olfactory stimuli. Sexual excitement of the female takes palce due to the scent produced by the pheromone glands of the androconia situated on the forewings of the male. Most male pheromones are effective only over short distance. In courtship display, the male moves round the female and make contact with its abdomen. If the female is receptive, she raises her wings so as to uncover the tip of her abdomen allowing the male to mate. While mating is in progress, one of the pair usually flies, clumsily dragging along the other, who hangs passively (Mathew 2011).

Flight: While most of the butterflies fly during day time (diurnal), a few butterflies, especially the skippers fly during night (nocturnal). The flight of butterfly may be of two kinds- fluttering or gliding. Butterflies that characteristically fly by fluttering the wings usually possess broad wings which they beat up and down. Gliding is a passive flight performed by butterflies either during migration or while moving from the canopy to the ground. Gliding is the usual flight pattern in certain large butterflies such as the Tree nymph, Idea malabarica (Mathew 2011).

Mud sipping/ Mud puddling: Adult butterflies frequently aggregate on damp soil mainly for their salt requirement. The newly emerged adults usually have enough reserve of sodium in their body. The males exhaust their sodium reserves during spermatogenesis while the female replenish their sodium reservethrough the sperms received from the males during copulation. Males make up for this loss of sodium by licking the sodium deposits contained in damp soil. The mud puddling aggregations usually comprise a large congregation of many species of butterflies. Only the male butterflies take part in mud puddling (Mathew 2011).

Basking: Butterflies being ‘cold-blooded’ organisms cannot generate enough heat from their own metabolism for flight. Therefore, butterflies bask in the sun with open wings to keep the thoracic muscles warm for flight. Thermal energy received from the sun is used to warm the surface of the wings. Basking may be dorsal or lateral. In the former, the wings are kept spread out while in the latter, the wings are held together above the body with the ventral surface kept perpendicular to the sun when the dark pigments on the underside of the wings absorb radiant energy warming the flight muscles of the thorax efficiently. Butterflies having white wings characteristically hold their wings in a V- shaped position in order to reflect the sun rays directly to the thorax. The black areas near the wing bases absorb the heat efficiently which is then directly transferred to the flight muscles. At dusk or during cloudy days, when solar radiation falls beneath the levels needed to ensure sufficient heating, butterflies seek shelter on the branches of trees. In the tropics, the flight activity lasts longer because of the longer duration of warm day hours (Mathew 2011).

Defence Mechanisms: All stages of butterflies are susceptile to a variety of natural enemies such as Spiders, Preying Mantis, Ants, Wasps, Parasitic Wasps, Parasitic Flies, Birds, Rats, Toads, Lizards and Snakes. Unlike other insects, butterflies do not have any specialised organs of defence. However, as a part of self defence, butterflies have developed various strategies to keep away from the predators. Warning coloration, camouflauge, accumulation of toxic materials in the body etc. are some of the adaptations found in butterflies (Mathew 2011).

Camouflage: The simplest form is copying the colour of the background or having dark and light stripes or having various patterns on the wings which render recognition of organisms difficult while resting. These complex patterns which make it difficult for predators to distinguish the outline of the butterfly from the environment are called "disruptive coloration". In order to escape from predators, the immature stages also present various adaptations. The larva may be variously coloured, worm-like and is provided with spines or worts to escape from predators. The larva of the lime butterfly Papilio demoleus resembles a bird dropping in the initial stages but later it becomes greenish perfectly matching with the leaf. Caterpillars of ceratin papilionids possess a gland known as osmeterium just behind the head. When disturbed, they may evert a horn-like appendage and eject a fluid on the predator. Caterpillars of Hesperiidae live inside a fold cut from the leaf edge. Larvae of Palm butterflies (Elymnias spp.) live inside rolled leaves. Symbiotic relationships between lycaenid caterpillars and ants are well known. Protective colouration (crypsis) is noticed in the larvae of Hairstreaks and Skippers which resemble their host plants in colour and pattern. Butterflies are potentially most vulnerable in the pupa stage and in order to escape from predators they have developed the ability to camouflage themselves by resembling their surroundings. The pupa of the Commom mime (Chilasa clytia) closely resembles a dead twig. This is also an example of protective colouration (Mathew 2011).

Migration: Like birds, butterflies also migrate. However, the reasons for migration are not fully worked out. It is presumed that butterflies migrate to tide over unfavourable conditions such as over crowding, scarcity of food, unfavourable weather conditions etc. The classical example of butterfly migration is that of the Monarch butterfly (Danaus plexipus) from Canada to Mexico, traversing a distance of 3200 km. In this case, migration begins with the onset of winter season and the return journey is undertaken during the spring. Since butterflies are short-lived, they cannot survive to complete the round trips and the return journey is usually undertaken by the offsprings (Mathew 2011). Mottled Emigrant (Catopsilia pyranthe), Common Albatross (Appias albina), Blue Tiger (Tirumala limniace) and the Common Crow (Euploea core) are some of the migrant butterflies in this country.