Graveyard of Civilization—destruction

In the future, human beings will suffer from survival crises due to disasters such as the depletion of earth's resources and radiation from the sky. Scientists screened out Homo habilis and Homo sapiens through genetic screening and ability tests. Homo sapiens used scientific means to reduce their size and occupy the earth's resources to establish a civilization base in Australia. Homo sapiens was left behind to survive on a resource-depleted continent. How could humans survive the disaster without technology? Isolated by the sea, could Homo sapiens guard Utopia and obtain eternal life?