Common ostrich
Common ostriches usually weigh from , or as much as two adult humans. The Masai ostriches of East Africa ("S. c. massaicus") averaged in males and in females, while the nominate subspecies, the North African ostrich ("S. c. camelus"), was found to average in unsexed adults. Exceptional male ostriches (in the nominate subspecies) can weigh up to . At sexual maturity (two to four years), male common ostriches can be from in height, while female common ostriches range from tall. New chicks are fawn in colour, with dark brown spots. During the first year of life, chicks grow at about per month. At one year of age, common ostriches weigh approximately . Their lifespan is up to 40–45 years.
Oestrus ovis
The adult fly is a bee-like insect about 10 to 12 millimetres (3/8–½ inches) long, slightly hairy with a banded, dark grey body and dull yellow head and legs. It is widely distributed across the world wherever sheep, deer and goats are found. This includes North America, Central America, the area round the Mediterranean Sea, The Middle East, Australia, Brazil and South Africa. Incidence of the fly in northern Europe has decreased in recent years.