Why is Australia called a country riding on the back of sheep?

Australia is called a country riding on the back of sheep because it has the most Mianyang and the most wool exports in the world. "There are more sheep than people" is a true portrayal of Australia.

The reason why there are many sheep in Australia is that Australia has a vast territory, and natural grasslands account for about half of the total land area. Grassland is flat and vast, suitable for large-scale development of animal husbandry. More than 200 years ago, there were no sheep in the huge Australian industry. 1788, the first batch of British immigrants came to Australia and brought 29 European sheep, but they could not adapt to the local natural environment and failed to survive. 1997, another batch of British immigrants came to Australia and introduced the famous merino sheep. This kind of sheep is prone to foot rot in wet and rainy England, but it has been cured in dry Australia. In addition, there are abundant pastures and mineral-rich water sources here, which makes merino sheep breed rapidly.