Gemsbok Oryx gazella mammal animal animals Bovidae Antelopes GEMS ORYGAZ adult Grassland Steppe desert East Africa Standing Herbivore rare threatened Sossusvlei Namibia March evening sunset Gemsbuck antelope savannah big antler horn horns landscape sun sunny sky elegant sunrise red Oryx-Antelope beautiful black kalahari orange travel safari game reserve wild wilderness wildlife group herd flock clouds meadow pasture grassland