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Pogona vitticeps, Photo: Michael Lahanas Cladus: Eukaryota
Pogona vitticeps, one month old, Photo: Michael Lahanas Name Pogona vitticeps Ahl, 1926 Vernacular Names ------- Pogona vitticeps, the Central (or Inland) Bearded Dragon, is a species of agamid lizard occurring in a wide range of arid to semi-arid regions of Australia. This species is often kept as a pet and exhibited in zoos. Description Pogona vitticeps was first described by Ernst Ahl in 1926, placing it in the genus Amphibolurus.[1] [2] Ecology and behavior This dragon is native to the semi-arid woodland, arid woodland, and rocky desert regions of Central Australia. They are skilled climbers, and often spend just as much time perching on tree limbs, fenceposts, and in bushes as they do on the ground. They spend the morning and early evening sunning themselves on an exposed branch or rock, and retreat to shady areas or underground burrows during the hottest parts of the afternoon. Bearded dragons do not vocalize, except to hiss softly when threatened. Instead, they communicate through color displays, posture, and physical gestures like arm waving and head bobbing. Bearded dragons are not social animals, but will sometimes gather in groups, especially in popular feeding or basking areas. At these times, a distinct hierarchy will emerge: the highest-ranking animals will take the best - usually the highest or sunniest - basking spots, and all other individuals arrange themselves lower down. If a low-ranking animal tries to challenge one of the dominant dragons, the dominant animal will demonstrate its superiority by bobbing its head and inflating its beard, at which point the challenger may signal submission by waving one of its forearms in a slow circle. If the low-ranking dragon does not submit, it will return the head-bob, and a standoff or fight may ensue. There are several different kinds of head bob gesture. These are: - Slow bowing motion - often used by adult females to signal submission to a male. - Fast bob - used by males to signal dominance (often accompanied by an inflated and/or blackened beard). - Violent bob - used by males just before mating. This bob is much more vigorous, and usually sets the animal's whole body in motion. Gravid females will often refuse the advances of a male by chasing him and lying on his back. There are also arm waving gestures that can be displayed by both male and the female theses are: -The male will only arm wave to show submission to a dominant male , whereas the female will arm wave to show that she is ready to mate followed by a slow head bob. Reproduction Central bearded dragons reach full sexual maturity around 18 months of age. Males will become very aggressive towards each other and will assert their dominance by inflating their beards and through fast head bobbing. Breeding typically occurs in the early spring Females will lay a clutch of eleven to thirty oblong-shaped eggs in a shallow nest dug in the sand. After being laid the eggs are buried and are left unattended. The eggs will hatch approximately 60 to 80 days later depending on the incubation temperature. In captivity, they can be incubated in a styrofoam fish box, but without a male lizard the eggs the female lay will not be fertile. However a female bearded dragon can retain sperm, and thus produce fertile eggs even after being separated from a male. Bearded Dragon courtship involves the male "head bobbing" to display dominance. If the female displays submissive behavior the male will use its mouth to grab the back of the females head and the male will also wrap its front legs around the females upper torso to keep her from moving. Copulation and insemination doesn't take very long. The gestation period averages about a month and a half. Captive breeding Captive Bearded Dragons world wide are threatened by Agamid adenovirus, a virus that when showing symptoms compromises the immune system of the dragon, and leads to death from other diseases, however majority of the infections are sub-clinical. Sub-clinically infected animals show no signs themselves but are active carriers of the disease and will infect other Bearded Dragons. When the female is ready to lay eggs she will generally stop eating and spend most of her time trying to dig 1. ^ Ahl,E. 1926. Neue Eidechsen und Amphibien. Zool. Anz. 67: 186-192 * Pogona vitticeps at the TIGR Reptile Database Source: Wikispecies, Wikipedia: All text is available under the terms of the GNU Free Documentation License |
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