Human Nature started as the 4 Trax in Sydney in late 1989 when Toby Allen (born 1973) and Phil Burton (born 1974) joined with brothers Andrew (born 1974) and Mike Tierney (born 1977). They represented Hurlstone Agricultural High School in a combined regional schools concert at the Bankstown Town Hall, on 27 November 1989. All four members had choir backgrounds and were inspired by groups from the Motown era, including the Four Tops. In Bankstown, they had sung The Penguins' hit "Earth Angel". Andrew later told Megan Riggs of What's on Highway Radio that it was the only song they knew and they were encouraged to listen to more Motown groups.