Eastern bearded dragon

Eastern bearded dragon
The Eastern Bearded Dragon, Pogona barbata
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Iguania
Family:	Agamidae
Genus:	Pogona
Species:	P. barbata
Binomial name
Pogona barbata Cuvier, 1829

The eastern bearded dragon or Jew lizard, Pogona barbata, is a lizard found in wooded parts of Australia. It is most common in eastern Australia south of Cape York Peninsula, but specimens have been collected from Cape York, through central Australia, and even from the west coast of Australia. It is a large species of grey-black colour distinguished from its relative, the central bearded dragon, Pogona vitticeps, by its less robust body and the row of spines along the lateral edge of the body, which continues over the forearm (Cogger, 1992). It tends to be more cryptic in its behaviour than the Central bearded dragon and performs its bearded display more often. It has an adult snout-tail length of about 24 inches (60 cm). When threatened, in addition to its beard display, it gapes – turning its mouth a very pale yellow colour.

Physical description

The eastern bearded dragon resembles its close relative the smaller central bearded dragon. It is usually grey-black in skin colour and is sometimes reddish-brown, yellowish-brown, or dark brown. Juveniles are paler in colour than the adults and have patterns that fade as they mature. As it matures it develops a hard to notice pale yellow, blue, or green tinge on the forepart of its head. The adult males can grow up to about 24 inches (60 cm), and females up to 20 inches (50 cm). The adult males have a dark grey to black "beard".

Behavior

Eastern Bearded Dragons are diurnal. They are semi-arboreal and perch on semi-high places retreating to lower and darker places when too hot. The eastern bearded dragon is also known to do the arm wave as a sign of submission or just for general communication. Their beard is displayed when agitated or threatened, or for territorial and mating displays. When agitated they also gape and hiss. The eastern bearded dragon is more aggressive than the central bearded dragon, demands more space and is less docile. The males are very territorial and only have submissive females and juveniles in their territory. Dominant males are usually the biggest dragons and get the highest perch.

Diet

Juvenile eastern bearded dragon in the undergrowth of a blackberry bush. Note that the dark spot at the tip of the nose is the shadow of the same bush.

The eastern bearded dragon feeds on a variety of small vertebrates and invertebrates including crickets, small grasshoppers, worms, beetles, katydids, small mice, and small reptiles. In captivity they also eat a few vegetables. These include clover and dandelion flowers.

Venom

In late 2005, University of Melbourne researchers discovered that Komodo dragons, Varanus komodoensis, Perenties, Varanus giganteus, other monitors, gila monsters, Heloderma suspectum, Iguanians such as Pogona barbata and beaded lizards, Heloderma horridum, are somewhat venomous. Previously, it had been thought that bites inflicted by these lizards were simply prone to infection because of bacteria in the lizards' mouths, but these researchers have shown that the immediate effects – at least in the Komodo dragon, spotted tree monitor, Varanus scalaris, and lace monitor – are caused by mild envenomation. The eastern bearded dragon "retains characteristics of the ancestral venom system, namely serial, lobular non-compound venom-secreting glands on both the upper and lower jaws . . .".

See also

• Bearded dragon

References

• Chris T. McAllister, Steve J. Upton, Elliott R. Jacobson and Wayne Kopit (1995-04). "A Description of Isospora amphiboluri (Apicomplexa: Eimeriidae) from the Inland Bearded Dragon, Pogona vitticeps (Sauria: Agamidae)". The Journal of Parasitology, Vol. 81, No. 2. The American Society of Parasitologists. Retrieved 2008-06-04. {{cite journal}}: Check date values in: |date= (help)CS1 maint: multiple names: authors list (link)
• Fry, Brian G., et al. (2006). "Early evolution of the venom system in lizards and snakes." Nature. Letters. Vol. 439/2 February 2006. Pdf file available for download at: [1]

External links

• Bearded Dragons basic caresheet
• Bearded Dragons forum