The Australian climate ranges from wet tropical in the northeast and northwest to arid in the centre. There were active volcanoes on the eastern mainland as recently as 4,600 years ago, and this is reflected in Aboriginal place names and creation stories. However, the Australian plate is moving north-northeast at a rate of about 6 to 7 cm a year and is currently in collision with the Eurasian plate and Pacific plate. A 2022 study by the industry lobby group, The Tech Council of Australia, stated that the Australian technology sector combined contributes $167 billion a year to the economy and employs 861,000 people. In 2020, Australia produced 27.7% of its electricity from renewable sources, exceeding the target set by the Commonwealth government in 2009 of 20% renewable energy by 2020. According to the Australian Council of Social Service, the poverty rate of Australia exceeds 13.6% of the population, encompassing over 3.2 million. It is the world's fourteenth-largest by nominal terms, and the 18th-largest by PPP. In 2022, defence spending was 1.9% of GDP, representing the world's 13th-largest defence budget. The executive branch of the Commonwealth government has overall control of the military through the minister of defence, who is subject to the decisions of Cabinet and its National Security Committee. In the performing arts, Aboriginal peoples have traditions of religious and secular song, dance and rhythmic music often performed in corroborees. Australian public intellectuals have also written seminal works in their respective fields, including feminist Germaine Greer and philosopher Peter Singer. Miles Franklin is the namesake of Australia's most prestigious literary prize, awarded annually to the best novel about Australian life. Their works are still popular; Paterson's bush poem "Waltzing Matilda" (1895) is regarded as Australia's unofficial national anthem. In the 19th century, Henry Lawson and Banjo Paterson captured the experience of the bush using a distinctive Australian vocabulary. Many Australians identify egalitarianism, mateship, irreverence and a lack of formality as part of their national identity. Contemporary Australian culture is diverse and reflects the country's Indigenous traditions, British and Irish heritage, and post-1945 history of multicultural immigration. In 2019, 30% of the Australian resident population, or 7,529,570 people, were born overseas. At that time, the indigenous population was estimated to have been between 315,000 and 750,000. More than 400 distinct Australian Aboriginal peoples have been identified across the continent, distinguished by unique names designating their ancestral languages, dialects, or distinctive speech patterns. Dispersing across the Australian continent over time, the population expanded and differentiated into hundreds of distinct groups, each with its own language and culture. Indigenous Australians is an inclusive term used when referring to both Aboriginal and Torres Strait islanders (the "first peoples"). The Torres Strait Islanders are a distinct people of Melanesian ancestry, indigenous to the Torres Strait Islands, which are at the northernmost tip of Queensland near Papua New Guinea, and some nearby settlements on the mainland. Indian Australians are Australians of Indian ancestry, and are the second-largest Asian Australian ancestry, comprising 3.1% of the total population. There is a growing self-declared indigenous population—including Torres Strait Islanders, who are of Melanesian descent. The dingo was introduced by Austronesian people that traded with indigenous Australians around 4000 B.C.E. Many plant and animal species became extinct after human settlement, including the Tasmanian Tiger. Only the southeast and southwest corners of the continent have a temperate climate and moderately fertile soil. Australia—owing to its size and isolation—is often dubbed the "island continent" and is sometimes considered the world's largest island. Australia, the continent and the country, may have been quite isolated at the beginning of the 20th century, but it entered the 21st century a culturally diverse land brimming with confidence, an attitude encouraged by the worldwide fascination with the land “Down Under” and demonstrated when Sydney hosted the 2000 Olympic Games. At the beginning of the 20th century, Nellie Melba was one of the world's leading opera singers, and later popular music acts such as the Bee Gees, AC/DC, INXS and Kylie Minogue achieved international recognition. The most striking characteristics of the vast country are its global isolation, its low relief, and the aridity of much of its surface. Australia is the last of lands only in the sense that it was the last continent, apart from Antarctica, to be explored by Europeans. On the other hand, whereas the landscape history of extensive areas in Europe and North America has been profoundly influenced by events and processes that occurred since late in the last Ice Age—roughly the past 25,000 years—in Australia scientists use a more extensive timescale that takes into account the great antiquity of the continent’s landscape. In simple physical terms, the age of much of the continent is certainly impressive—most of the rocks providing the foundation of Australian landforms were formed during Precambrian and Paleozoic time (some 4.6 billion to 252 million years ago)—but the ages of the cores of all the continents are approximately the same. The surf lifesaving movement originated in Australia in the early 20th century, following the relaxation of laws prohibiting daylight bathing on Australian beaches. The Australian national cricket team competed against England in the first Test match (1877) and the first One Day International (1971), and against New Zealand in the first Twenty20 International (2004), winning all three games.