Estimates of when the first indigenous Australians; or Aboriginal Australians; settled in the continent range from 16;000 years to 120;000 years ago. They lived a hunter-gatherer lifestyle and were semi-nomadic until the British arrived in 1788 to colonize Australia. At that time; there were an estimated 500;000 indigenous people (approximately the same as the aboriginal population today) who spoke 250 to 300 languages and 600 dialects. With the arrival of Europeans; the aboriginal Australians lost much of their land and freedom; and diseases such as smallpox and measles decimated their population.