Karoo an immense volume of rocks which was formed, geologically speaking, in a short period of time. Although almost the whole of the Great Karoo is situated on Karoo Supergroup rocks, the geological Karoo rocks extend over a very much larger area, both within South Africa and Lesotho, but also beyond its borders and onto other continents that formed part of Gondwana. The Karoo Supergroup was formed in vast inland basin starting 320 million years ago, at a time when the part of Gondwana which would eventually become Africa lay over the South Pole. Icebergs that had calved off the glaciers
Karoo chat similar grey form of the female mountain wheatear, from which it also differs in having a grey (not white) rump and completely white outer tail feathers. Its larger size and all-white outer tail feathers prevent confusion with the tractrac or sickle-winged chats. The Karoo chat has "chak-chak" and "trrat-trrat" calls. The Karoo chat builds a cup-shaped nest of straw and leaves on the ground, usually under a bush or shrub. It lays two to four green eggs. This species is monogamous, mating for life. The Karoo chat is usually seen singly or in pairs. It forages from the ground for