Thomson's gazelles are found mainly in Tanzania and Kenya, and there's a small population in southern Sudan. They form herds of up to 200 individuals, but form much looser groups while migrating. Like other gazelles they perform 'stotting' or 'pronking' when alarmed by a predator. This involves jumping repeatedly with legs stiff and back curved and landing on all fours. Stotting is thought to demonstrate to the predator the amount of energy the gazelle has and thus to forestall a long chase by telling it 'I'm too athletic for you to catch'.

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