es, when large populations of springbok roamed the Kalahari Desert and Karoo, millions of migrating springbok formed herds hundreds of kilometres long that could take several days to pass a town. These mass treks, known as trekbokking in Afrikaans, took place during long periods of drought. Herds could efficiently retrace their paths to their territories after long migrations. Trekbokking is still observed occasionally in Botswana, though on a much smaller scale than earlier. Springbok often go into bouts of repeated high leaps of up to 2 m (6 ft 7 in) into the air – a practice known as pronking (derived from the Afrikaans pronk, "to show off") or stotting. In pronking, the springbok performs multiple leaps into the air in a stiff-legged posture, with the back bowed and the white flap lifted. When the male shows off his strength to attract a mate, or to ward off predators, he starts off in a stiff-legged trot, leaping into the air with an arched back every few paces and lifting the flap along his back. Lifting the flap causes the long white hairs under the tail to stand up in a conspicuous fan shape, which in turn emits a strong scent of sweat. Although the exact cause of this behaviour is unknown, springbok exhibit this acti