Australia is made up of several states and territories with a population of over 21 million people that primarily speak English. The climate varies widely across the country from deserts to tropical regions to grasslands. Notable animals include kangaroos, koalas, and platypuses. Aboriginal culture has blended with immigrants from Europe, Asia, and Africa to influence Australia's diverse culture. Popular sports include Australian rules football and cricket. Famous tourist attractions include the Sydney Opera House, the Great Barrier Reef, and Ayers Rock.