Catastrophism

Catastrophism is the view that Earth’s features were shaped chiefly by sudden, large-scale events, rather than by gradual processes alone.

Georges Cuvier: French naturalist Georges Cuvier established comparative anatomy and helped found vertebrate paleontology. His fossil studies supplied influential evidence for successive catastrophes and extinctions.
Mass extinction: A mass extinction is a geologically brief interval in which a large share of species disappears worldwide. Catastrophist explanations connect abrupt biological losses to sudden environmental upheavals.
Cretaceous–Paleogene extinction event: The Cretaceous–Paleogene extinction event, about 66 million years ago, eliminated non-avian dinosaurs and many other groups. It is linked to a large impact and illustrates a catastrophe with global consequences.
Paleontology: Paleontology is the scientific study of ancient life through fossils. Cuvier’s catastrophism grew from comparing fossils across rock layers.
Theory of the Earth: James Hutton’s 1788 account argued that geological processes operating over immense time shaped Earth. Hutton’s gradualist account became catastrophism’s leading geological rival.
Impact event: An impact event occurs when an asteroid or comet collides with a planetary body. Large impacts can produce abrupt changes on a global scale.
Chicxulub crater: Chicxulub is a large impact crater buried beneath Mexico’s Yucatán Peninsula. Its age and evidence of impact connect it to the end-Cretaceous catastrophe.
Extinction: Extinction is the permanent disappearance of a species or other taxonomic group. Catastrophism helped establish extinction as a real feature of Earth’s history.
Charles Lyell: Charles Lyell was a British geologist who championed uniformitarian explanations in the nineteenth century. His Principles of Geology popularized gradual change against catastrophic interpretations.
Volcanic winter: A volcanic winter is temporary global cooling caused by volcanic aerosols reflecting sunlight. It shows how a sudden geological event can rapidly alter climate.

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