We May Be Living Through a Sixth Mass Extinction-but Scientists Think Some of the First Five Never Happened

Key Points:

• New research using an AI model called OneStrata challenges the traditional view of Earth's five major mass extinctions, suggesting that several occurred gradually over millions of years rather than abruptly.
• OneStrata, developed by Shuzhong Shen and colleagues at Nanjing University, analyzes fossil data at a much finer resolution—around 1,000 years—compared to previous studies that grouped fossils into million-year timespans.
• The study finds that the Late Devonian, end-Triassic, and end-Cretaceous extinctions unfolded over extended periods, contrasting with rapid events like the End-Permian extinction, which happened in about 63,000 years.
• This research highlights the complexity of extinction events, noting that while biodiversity declined, species extinction and replacement may have occurred simultaneously, complicating the definition of "mass extinction."
• The number and nature of mass extinctions remain debated, with estimates ranging from three to twenty, and ongoing concerns that current human-driven environmental changes may constitute a sixth mass extinction.