Great bustard it well camouflaged in open habitats. Immature birds resemble the female. The eastern subspecies ("O. t. dybowskii") is more extensively grey in colour in both sexes, with more extensive barring on the back. The great bustard has long legs, a long neck and a heavy, barrel-chested body. It is fairly typical of the family in its overall shape and habitat preferences. Three other bustard species overlap in range with this species: the Macqueen's ("Chlamydotis macqueenii"), houbara ("Chlamydotis undulata") and little bustards ("Tetrax tetrax"). However, none of these attains the plumage coloration nor approach the body sizes of this species. Thus,
Porphyria cutanea tarda Porphyria cutanea tarda Porphyria cutanea tarda (PCT) is the most common subtype of porphyria. The disease is named because it is a porphyria that often presents with skin manifestations later in life. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood. Hepatoerythropoietic porphyria has been described as a homozygous form of porphyria cutanea tarda, although it can also be caused if two different mutations occur at the