When talking about flightless birds, the first species many people think of is the ostrich. And everybody knows that the ostrich lives in Africa. Do you know there are flightless birds in Australia and America that look just like the ostrich? Check the video to find out more: 

The two surviving species of ostrich inhabit Africa, though some were shipped to Australia, escaped and lived in the wild. Historically, there used to be ostriches in Asia. China had this awesome giant bird until the last ice age. 

The ostrich is the largest bird extant. It can be as tall as 2.1-2.8 meters, weighing 65-145 kilo, roughly two adult men. Its eggs are the largest eggs of all extant birds. It is also the fastest bird on land, with a top speed of 70 km/h and a single stride of 3-5 meters. 

The ostrich is distinctive with a conspicuous black-and-white combination, almost naked skin on the head and neck, with big eyes and beautiful long eyelashes. If you can get close enough, you can see that the bird has two toes on each foot, different from most birds. 

As the second-largest living bird, the emu is endemic to Australia, where there is a huge population. The emu can be 1.9 meters high, weighing 18-60 kilo. The most apparent difference between the ostrich and the emu is that the emu's wings are very short and not distinguishable, while the ostrich has two big wings though they cannot be used to fly. Also, the emu's neck is covered with feathers, not naked like the ostrich. It has three toes rather than two. 

The rhea is endemic to South America. It looks just like the emu but without the bluish face and neck. The rhea can reach up to 1.7 meters and weighs about 40 kilos. It has three toes. 

There are other two flightless bird species in Australia: the cassowary and the kiwi. Both are quite easy to recognize. 

The cassowary has a bright blue neck and a casque on the head. It is called the "most dangerous bird in the world" because of its dagger-like claw. Records even show at least two human deaths were caused by the bird. 

The kiwi, on the other hand, is much more harmless. The bird is just about the size of a chicken with wings so small that they are almost invisible. One fun fact is, the small bird lays big eggs. It is endemic to New Zealand and has become the country's symbol. 

(All images via VCG)

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