Struthio camelus

The largest bird on earth is the African ostrich, which is also a flightless bird. In biological classification, it is the only species of the family Struthionidae. The African ostrich is about 183-300 cm long, 240-280 cm tall, and weighs 130-150 kg. The female bird is slightly smaller. The snake-like slender neck supports a very small head with a short, flat, triangular mouth composed of several keratin sheaths.

The main feature of the African ostrich is that the keel is not well developed and it cannot fly. It is also the only two-toed bird in the world. It has a dangerous nail about 7 cm long on each big toe of its feet. The hind limbs are strong and powerful, suitable for running.

The African ostrich lives in the desert grasslands and savannahs of Africa. It is widely domesticated in many countries because of its high economic value of feathers, skins and meat, fast growth, strong fertility, easy breeding and strong disease resistance.

The African ostrich is the only species in the order Struthionidae and is also a representative of walking birds. The ancestor of the ostrich is also a flying bird. How it became what it is today is closely related to its living environment. African ostriches are tall, have long necks, and sharp eyes. When foraging in groups, the intervals between each bird raising its head are irregular, one after another, so there are always some individuals looking up, so that they can find enemies in time and inform other animals to quickly avoid them. They run very fast in the desert, with each step reaching 3.5 meters. They can run continuously at a speed of 50 kilometers per hour, can run for more than 5 minutes, and sprint at a speed of more than 70 kilometers per hour. They can also cross obstacles more than 5 meters high. They like to drink water and bathe.

The ostrich is a primitive remnant bird, which represents an evolutionary direction in which animals in open grasslands and desert environments gradually develop towards tallness and good running. At the same time, the ability to fly gradually weakens until it is lost. The running ability of the African ostrich is amazing. Its toes tend to be reduced because it is suitable for running. It is the only bird in the world with only two toes, and the outer toe is smaller, while the inner toe is particularly developed. It can jump 2.5 meters in the air and sprint at a speed of more than 70 kilometers per hour. At the same time, the sturdy legs are the main defensive weapon of the African ostrich, and can even kill lions and leopards.

African ostriches mainly live in deserts, grasslands, and scrublands. The Somali species sometimes enters dense thorny scrub and is even found on steep rocky plateaus in southwestern Africa.

It has a very strange appearance, with a very small head supported by a long and thin neck like a snake, and a short and flat triangular beak made up of several keratin sheaths. The upper beak is yellow, the lower beak is slightly pink, and there are two big brown eyes like frog eyes, which are bright and sharp. The trunk is short and thick, the sternum is flat, and there is no keel protrusion. There is a pair of short wings on it that are very disproportionate to the body. They have degenerated and have no flight feathers, so they cannot fly. The feathers of adult male birds are obviously black and white, while the feathers of adult female birds are mostly gray-brown. There are only two toes left, and there are no feathers on the strong legs. They stand on two toes, and the larger one is like a hoof. This is the unique adaptation of the ostrich, in order to run fast in order to cope with sudden danger. The huge eyeballs of the ostrich, with thick black eyelashes, are the largest eyeba