From - Wikipedia & Earth Unreal,
Edited by Amal Usawatta,
This species is a Five-banded gliding lizard (Draco quinquefasciatus).Draco is a genus of agamid lizards that are also known as flying lizards, flying dragons or gliding lizards. These lizards are capable of gliding flight via membranes that may be extended to create wings formed by an enlarged set of ribs. They are arboreal insectivores.
While not capable of powered flight they often obtain lift in
the course of their gliding flights. Glides as long as 60 m (200 ft)
have been recorded, over which the animal loses only 10 m (33 ft) in
height, which is quite some distance, considering that one lizard is only
around 20 cm (7.9 in) in total length, tail included. They are
found across Southeast Asia and southern India. and are fairly common in
forests, areca gardens, teak plantations and
shrub jungle.
Carl Linnaeus described the genus in 1758, with the type species being Draco volans. The name of the genus is from the Latin term for mythological dragons. In the early and mid 20th century, there was controversy about their gliding capabilities, with some authors suggesting that the patagia were solely for display, but research in the late 1950s firmly established the gliding function of the patagia.
Draco taeniopterus Gunther, 1861 from Bulon Island, Thailand
The lizards are well known for their "display structures" and ability to glide long distances using their wing-like, patagial membranes supported by elongated thoracic ribs to generate lift forces. The hindlimbs in cross section form a streamlined and contoured airfoil, and are also probably involved in generating lift. Gliding is both used to escape predators, and as the primary means of moving through their forest habitat. The folding and unfolding of the membrane is controlled by the iliocostalis and intercostal muscles, that in other lizards are used to control breathing. At takeoff, the lizard jumps and descends headfirst, orientating itself so that the underside of the body is parallel to the ground. During flight, the back arches, forming the patagium into a cambered surface, and the forelimbs grab the front of the patagium, forming a straight front edge to the aerofoil. The forelimbs are used to manipulate the patagium in order to adjust the trajectory during flight. Maximum gliding speeds have been found to be between 5.2 and 7.6 metres per second, depending on the species. During the landing process, the glide is mostly horizontal. Immediately before landing, the forelimbs release the patagium. The landing is forefeet-first, followed by hindfeet. The shape of the gliding membrane does not correlate with body size, meaning the larger species have proportionately less lift-generating surface area and consequently higher wing loading.
Habitat and ecology
Members of Draco are primarily arboreal, inhabiting tropical rainforests, and are almost never found on the forest floor. They are insectivorous, primarily feeding on ants and termites The colour of the patagium is strongly correlated to the colour of the local falling leaves, likely as camouflage against predatory birds
Life restoration of the weigeltisaurid Weigeltisaurus jaekeli, one of the oldest known gliding reptiles
Social behaviour and reproduction
Draco lizards are
highly territorial, with the home range consisting of one or a few trees. The
trees are actively guarded by males, with territory-less males searching the
forest landscape in search of vacant areas. Experimental studies have
determined that suitable unoccupied territories were claimed within a few hours
of the removal of a dominant male. Females move freely through the territories.
The patagium is used as a display structure during courtship and territorial
disputes between rival males, alongside the opening of a colourful dewlap The dewlap is translucent, and deliberately orientated
perpendicular to the orientation of the sun during display in order to enhance
visibility. Draco is sexually dimorphic, with females being larger than males.The
only time a female flying lizard ventures to the ground is when she is ready to
lay her eggs. She descends the tree she is on and makes a
nest hole by forcing her head into the soil. She then lays 2–5 eggs before
filling the hole and guards the eggs for approximately 24 hours, but then
leaves and has nothing more to do with her offspring
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