Karoo

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Map of the two Karoo ecoregions as delineated by the WWF on a satellite image from NASA. The yellow line encloses the two ecoregions, with the green line separating the Succulent Karoo to the west, from the Nama Karoo to the east.[n 1]

The Karoo (a Khoisan word of uncertain etymology[1]) is a semidesert natural region of South Africa. It consists of two closely related ecoregions – the Nama Karoo, which has mostly summer rainfall, and the Succulent Karoo, which has predominantly winter rain. The Nama Karoo has three main subregions – the Upper Karoo in the north – which is divided from the Great Karoo in the middle by the Great Escarpment, thus the Upper Karoo rivers flow northwards into the Orange River – and the Little Karoo in the south. The western section is the Succulent Karoo, situated in a winter rainfall region near the Atlantic coast.

In geological terms, the Karoo Supergroup refers to an extensive and geologically recent (100- to 260-million-year-old) sequence of sedimentary and igneous rocks, which is flanked to the south by the Cape Supergroup, and to the north by the more ancient Witwatersrand Supergroup. It covers two-thirds of South Africa[n 2] and extends in places to 8,000 m below the land surface, constituting an immense volume of rocks which was formed, geologically speaking, in a short period of time.[2][3]

Geological history[edit]

Extinct Karoo vertebrates

Bradysaurus
Lystrosaurus

The Great Karoo has an area of more than 400,000 km2 (150,000 sq mi). From a geological point of view, it has been a vast inland basin for most of the past 250 million years. At one stage, the area was glaciated; the evidence for this is found in the widely distributed Dwyka tillite. Later, at various times, there were great inland deltas, seas, lakes, and swamps from which formed enormous deposits of coal, today one of the pillars of South Africa's economy. Ancient reptiles and amphibians prospered in the wet forests, and their remains have made the Karoo famous amongst palaeontologists.

Flat topped hills (called Karoo Koppies) are highly characteristic of the southern and southwestern Karoo landscape. These hills are capped by hard, erosion resistant dolerite sills. This is solidified lava that was forced under high pressure between the horizontal strata of the sedimentary rocks that make up most of the Karoo’s geology. This occurred about 180 million years ago, when huge volumes of lava were extruded over most of Southern Africa and adjoining regions of Gondwana, both on the surface and deep below the surface between the sedimentary strata. Since this massive extrusion of lava, Southern Africa has undergone a prolonged period of erosion exposing the older softer rocks, except where they were protected by a cap of dolerite.

About 180 million years ago, volcanic activity took place on a titanic scale, which brought an end to a flourishing reptile evolution.[4] These genera represent some of the extinct animals of the Karoo:

The first Karoo fossils were discovered in 1838 by Scots-born Andrew Geddes Bain at a road cutting near Fort Beaufort. He sent his specimens to the British Museum, where fellow Scotsman Robert Broom recognised the Karoo fossils' mammal-like characteristics in 1897.[4]

Modern history[edit]

The first European settlers who landed in the Cape of Good Hope in 1652 began to move inland when arable land around the Cape became scarce. The Europeans who first settled in the Karoo were the trekboers in the mid-1700s. Before that time, large herds of antelope, zebra and other large game roamed the grassy flats of the region. The Khoi and Bushmen, last of the southern African Stone Age peoples, wandered far and wide. The Bantu people to the east of the Karoo did not occupy this arid region due to the lack of summer rainfall which prevented the farming of cattle. The two ethnic groups mentioned above differed substantially in their cultures and lifestyles: the Hottentots were described as grazers of sheep and cattle, while the Bushmen were hunter-gatherers. (These were the original names given to these tribes[clarification needed] by the Dutch. The terms may not be regarded as politically correct today). With the occupation of the region by European settlers, sheep gradually replaced the game and the cover of grass degenerated, owing to changes in the pattern of grazing and in the climate.

Starting in the middle years of the 19th century, a railway track was extended into the Karoo from Worcester in the south. This was eventually extended into Bechuanaland, South West Africa, Johannesburg, Rhodesia, and far beyond. The impact of this railroad on the history of southern Africa is difficult to exaggerate.

During the Second Anglo-Boer War of 1899–1902, three Republican commando units, reinforced by the rebels from the Cape Colony, conducted widespread operations throughout the Karoo. Countless skirmishes took place in the region, with the Calvinia magisterial district, in particular, contributing a significant number of fighters to the Republican cause. Fought both conventionally and as a guerrilla struggle over the Karoo's vast expanses, it was a bloody war of attrition wherein both sides used newly developed technologies to their advantage. Numerous abandoned blockhouses can still be seen at strategic locations throughout the Great Karoo; a prime example is located next to the Geelbeks River, 12 km (7.5 mi) outside the town of Laingsburg.

Currently, sheep farming is still the economic backbone of the Karoo, with other forms of agriculture established in areas where irrigation is possible. Lately, game farms and tourism have also started to make an economic impact.

Little Karoo[edit]

As the name implies, the Little Karoo is the smaller (and more southerly) of the two Karoo subregions. Locally, it is usually called the Klein Karoo, which is Afrikaans for Little Karoo. Geographically, it is a valley (bounded on the north by the Swartberg, and on the south by the Langeberg and Outeniqua mountains). Although the boundaries of the region are not strictly defined, most people consider the western limit of the Little Karoo to be in the region of Barrydale and the eastern extremity around Uniondale.

The main town of the region is Oudtshoorn. Other towns/settlements in the region include Ladismith, Calitzdorp, and De Rust, and well-known mission stations such as Zoar, Amalienstein, Barrydale, and Dysselsdorp. On the railway line Cape Town-Johannesburg lies the historical town of Matjiesfontein, seat of majestic Lord Milner hotel, still extant.

This area was explored by European settlers in the late 17th century, who encountered Khoisan people living in this rather dry area. Modern farming methods have brought productivity and wealth to this district.

Karoo in literature[edit]

Poet Thomas Hardy wrote in his poem The Dead Drummer:[5]

Young Hodge the Drummer never knew -
Fresh from his Wessex home -
The meaning of the broad Karoo,
The Bush, the dusty loam,
And why uprose to nightly view
Strange stars amid the gloam.

A blockhouse in the eastern Karoo

In Bridge-Guard in the Karroo, Rudyard Kipling evoked the loneliness experienced by blockhouse soldiers at Ketting station on the Dwyka River while guarding the Karoo railway track, a lifeline during the South African War (excerpts):[6]

Sudden the desert changes,
  The raw glare softens and clings,
Till the aching Oudtshoorn ranges
  Stand up like the thrones of Kings –

We hear the Hottentot herders
  As the sheep click past to the fold –
And the click of the restless girders
  As the steel contracts in the cold –

And the solemn firmament marches,
  And the hosts of heaven rise
Framed through the iron arches –
  Banded and barred by the ties, ...

Karoo gallery

Dolerite outcrops of the Nuweveld range, central Great Karoo
Nuweveld range and its foothills, central Great Karoo
Cape Fold Belt at Anysberg, northern Little Karoo

See also[edit]

Notes[edit]

  1. ^ National boundaries are shown in black on the map. Note that the ecoregions given the name "Karoo" do not coincide exactly with the geographical boundaries of what is traditionally recognized as The Karoo sensu stricto. For example, few people in southern Africa would hold that 'The Karoo' proper extends into Namibia.
  2. ^ Karoo geology covers a large area to the north and east of the Karoo ecoregions, including all of Lesotho.

References[edit]

  1. ^ Oxford English Dictionary, Second Edition, 1989, OED Online
  2. ^ Bulpin, Thomas Victor (1985). "7. The lost world of the dinosaurs: The Karoo sequence". Scenic Wonders of Southern Africa. Books of Africa. pp. 199–221. ISBN 0-949956-26-0. 
  3. ^ Reid, R. (ed.) (2005). "7. The lost world of the dinosaurs: The Karoo sequence". The Story of Earth & Life. Struik Publishers. pp. 199–221. ISBN 1-77007-148-2. 
  4. ^ a b c Walton, Christopher (ed.) (1984). "Anatomy of South Africa: 200 million years ago". Atlas of Southern Africa. The Reader's Digest Association South Africa. pp. 14–15. ISBN 0-947-008-02-0. 
  5. ^ The Dead Drummer
  6. ^ Hamer, Mary. ""Bridge-Guard in the Karroo": Notes". Retrieved 22 April 2012.  The poem was first published in The Times of 5 June 1901.

External links[edit]

Coordinates: 32°21′S 22°34′E / 32.350°S 22.567°E / -32.350; 22.567