Denis-Huot / Common ostrich (Struthio camelus), female, standing at waterhole in front of Grant's zebras (Equus quagga boehmi). Tsavo East National Park, Kenya.

Nick Garbutt / Egg size comparison to scale: extinct Elephant bird (Aepyornis maximus) - shell reconstructed from fragments found in dry river beds in southern Madagascar - and Common ostrich (Struthio camelus). Pho...

Nick Garbutt / Egg size comparison to scale: extinct Elephant bird (Aepyornis maximus) and Common ostrich (Struthio camelus). Photographed with multiple flash set up.

Charlie Hamilton-James / Four Ostrich (Struthio camelus) and a lone Thompson's gazelle (Eudorcas thomsonii) silhouetted at dawn, Topi Plain, Masai Mara, Kenya.