Knowra Extinction event Extinction event An extinction event is a geologically brief interval when many species disappear from the fossil record worldwide. It can result from rapid environmental change, catastrophic impacts, or interacting pressures.
Asteroid impact : The collision of an asteroid with a larger body, including Earth, releasing immense energy and debris. The Chicxulub impact rapidly altered climate and ecosystems at the end of the Cretaceous.
Cretaceous–Paleogene extinction event : A mass extinction about 66 million years ago that eliminated non-avian dinosaurs and many other species. It is the best-known event, associated with the Chicxulub impact.
Fossil record : The preserved remains and traces of past organisms found in geological materials. Extinction timing and taxonomic losses are inferred primarily from fossils.
Extinction selectivity : The nonrandom pattern in which some traits, habitats, or groups face greater extinction risk than others. Different events eliminated distinct groups, revealing which organisms were vulnerable to their particular stresses.
Adaptive radiation : The rapid diversification of a lineage into multiple forms adapted to different ecological roles. Vacant niches after an extinction can enable surviving lineages to diversify.
Flood basalt : A vast outpouring of basaltic lava that covers large areas over relatively short geological intervals. Large eruptions can release gases that drive warming, cooling, and ocean stress.
Permian–Triassic extinction event : A mass extinction about 252 million years ago, the most severe known loss of life in Earth's history. Its scale and association with Siberian Traps volcanism make it a key comparison.
Geological time scale : A system for organizing Earth's history into nested intervals based on rocks, fossils, and chronology. It provides the framework for locating extinction pulses in deep time.
Extinction debt : The delayed loss of species after environmental change has already made their survival unlikely. Fossil boundaries may record losses that unfolded after the initiating disruption.
Ecological release : An increase in a population's abundance or ecological range after competitors or predators decline. Survivors may expand when extinction removes ecological constraints.
Show all 28