5 female ostriches may lay their eggs in one scrape (nest) but only the major female incubates them. Being able to recognise her own eggs she ensures that they are in the centre. The rest will be moved to the side with many not be incubated.
Chicks hatch with their eyes open and a coat of black tipped spiky down (fine fur) on their backs which makes them look like hedgehogs.
Because ostriches lack an egg tooth they have to rely on muscular spasms to break from their shells, this can take 9 hours. During this process they ingest part of the yolk sac which sustains them over the first 24 hours of life outside of the shell.
Of up to 40 eggs laid (by 5 females) only half may be incubated as even an ostrich is not big enough to cover them all. Of these only 7.5 may hatch with a survival rate of just 12% due cold weather and predation by caracals, martial eagles and jackals.
The booming call of the ostrich, which is made mainly at night, resembles a lion’s roar.
Whilst most birds have four toes the ostrich only has two, this appears to be an adaptation for running. However, they run on just one toe with the second being used for balance.
The males mating dance, known as “kantling”, is quite spectacular. They will approach the female with feathers raised before dropping to their knees and rocking from side to side as he waves his wings and twists his neck.
At 5 cm wide, the ostrich has the largest eyeball of any land-living animal. This along with its long neck allows it to see over the long distances of its flat habitat.