New Plankton Species Evolved Within Thousands of Years After Chicxulub Impact
Approximately 66 million years ago, the Chicxulub asteroid impact triggered massive global fires, climate shifts, and the extinction of dinosaurs and many other species. However, a new study from the University of Texas at Austin, published in Geology, reveals that life recovered much faster than previously estimated. Researchers, led by Chris Lowery, found that new species of microscopic plankton, such as the foraminifera Parvularugoglobigerina eugubina (P. eugubina), emerged within just a few thousand years—possibly under 2,000 years—after the disaster. This rapid evolution contrasts sharply with typical speciation timelines that span millions of years. The team refined the recovery timeline using helium-3 isotope concentrations in ocean sediments from six K/Pg boundary sites across Europe, North Africa, and the Gulf of Mexico. Helium-3 accumulates steadily, allowing precise sedimentation rate calculations despite post-impact disruptions like increased erosion from vegetation loss and the disappearance of calcareous plankton. These changes had previously skewed estimates, suggesting recovery took tens of thousands of years. The study indicates 10 to 20 new foraminifera species appeared within about 6,000 years, highlighting life's resilience. Co-author Timothy Bralower from Penn State noted this 'geologic heartbeat' recovery offers hope for modern ecosystems facing anthropogenic threats.
