Male Impala: Lobo Region, Serengeti National Park.
Impalas range between 73 and 92 cm (29 and 36 in) tall. Average mass for a male impala is 46 to 76 kg (100 to 170 lb), while females weigh about 37 to 50 kg (82 to 110 lb). They are normally reddish-brown in color (hence the Afrikaans name of "Rooibok"), have lighter flanks and white underbellies with a characteristic "M" marking on the rear. Males, referred to as rams, have lyre-shaped horns, which can reach up to 90 centimeters in length. Females, referred to as ewes, have no horns. [wiki]