This spring, up to 16 states across the US will see a natural phenomenon of spectacular proportions not seen in over 200 years, as an estimated trillion periodical cicadas emerge in the same season. While there are over 1,500 different species of cicada, only seven emerge as a brood every 7 years, 13 years or 17 years. Because these cycles are all prime numbers, it is incredibly rare that the different broods emerge during the same year. But 2024 is one of those years. The Briefing's Simon Beaton spoke with one of Australia's leading cicada experts, Lindsay Popple, to find out more about these strange insects, and what a trillion cicadas will mean for the US. See omnystudio.com/listener for privacy information.