massautrýming

Massautrýming is an Icelandic term that translates to "mass extinction." It refers to a widespread and rapid decrease in the biodiversity on Earth. During a mass extinction event, a significant percentage of species on the planet are wiped out. These events are often characterized by the extinction of a large number of life forms across diverse groups of organisms, including plants, animals, fungi, and microorganisms.

Geological and paleontological evidence indicates that Earth has experienced several major mass extinction events throughout its history. The most well-known include the end-Ordovician, late Devonian, end-Permian, end-Triassic, and end-Cretaceous extinctions. The end-Permian extinction, often called the "Great Dying," is considered the most severe, with an estimated 96% of marine species and 70% of terrestrial vertebrate species becoming extinct. The end-Cretaceous extinction is famously associated with the demise of non-avian dinosaurs, likely caused by an asteroid impact.

The causes of mass extinctions are varied and can include catastrophic geological events such as massive volcanic eruptions, significant changes in sea level, and asteroid or comet impacts. Climate change, both warming and cooling, and shifts in atmospheric or oceanic composition also play crucial roles. The recovery of biodiversity after a mass extinction can take millions of years, with new species evolving to fill the ecological niches left vacant by the extinct organisms. Understanding past mass extinctions helps scientists assess the vulnerability of current ecosystems and biodiversity to ongoing environmental changes.