The Permian-Triassic extinction event, also known as the 'Great Dying', was the most severe extinction event in Earth's history, resulting in the loss of approximately 96% of marine species and 70% of terrestrial vertebrate species.

The Cretaceous-Paleogene extinction event, commonly known as the Chicxulub impact, is estimated to have caused the extinction of approximately 75% of all plant and animal species on Earth, including the non-avian dinosaurs.

While asteroid impact, volcanic eruptions, and sea-level changes are all potential causes of the Ordovician-Silurian extinction event, a gamma-ray burst is not a widely accepted hypothesis.

The Devonian-Carboniferous extinction event is believed to have been primarily caused by a combination of climate change and habitat loss, resulting in the extinction of approximately 70% of marine invertebrate species.

The Triassic-Jurassic extinction event, which occurred approximately 200 million years ago, marked the end of the dominance of dinosaurs and the rise of mammals as the dominant land animals.

Adaptive radiation is the process by which a group of organisms rapidly diversifies into a variety of new forms, each adapted to a specific ecological niche, following a mass extinction event.

The Permian-Triassic extinction event is associated with the Siberian Traps, a massive volcanic eruption that released large amounts of greenhouse gases and caused global warming.

The Cretaceous-Paleogene extinction event is believed to have occurred over a very short period of time, possibly as short as a single day, due to the impact of a large asteroid or comet.

The Ordovician-Silurian extinction event, which occurred approximately 444 million years ago, is associated with the disappearance of the trilobites, a group of marine arthropods that were common during the Paleozoic Era.

The Chicxulub impactor is the name given to the asteroid or comet that is believed to have struck the Earth approximately 66 million years ago, causing the Cretaceous-Paleogene extinction event.

The Triassic-Jurassic extinction event, which occurred approximately 200 million years ago, is associated with the rise of flowering plants, which became the dominant group of land plants.

The Permian-Triassic extinction event, also known as the 'Great Dying', is estimated to have caused the extinction of approximately 95% of all marine species and 70% of terrestrial vertebrate species.

The Cretaceous-Paleogene extinction event, commonly known as the Chicxulub impact, is associated with the disappearance of the dinosaurs, except for the ancestors of modern birds.

Natural selection is the process by which species adapt to new environmental conditions following a mass extinction event, resulting in the survival of those individuals with traits that are better suited to the changed environment.

The Permian-Triassic extinction event, which occurred approximately 252 million years ago, is associated with the rise of reptiles as the dominant land animals, replacing the amphibians that were dominant during the Carboniferous Period.