fossil record: Quick Facts

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Diagram comparing two columns of rock layers, labeled A and B, each containing distinct fossil illustrations at various depths. The matching fossils in corresponding layers show how geologists use fossils to determine the relative ages of rock layers, even when the sections are separated by 200 miles.

Map depicting the ancient supercontinent Gondwana, with colored bands showing the overlapping geographic home ranges of four prehistoric species-Cynognathus, Lystrosaurus, Glossopteris, and Mesosaurus-extending across present-day South America, Africa, India, Antarctica, and Australia.

A vertical geologic time scale chart spanning from 650 million years ago to the present, with colored bands for each era and period. Illustrations and labels highlight key evolutionary events such as the appearance of skeletal elements, first fishes, land plants, amphibians, reptiles, dinosaurs, mammals, and humans.

Dr. Jingmai O'Connor smiles and gestures toward a fossil of Archaeopteryx on display at the Field Museum, with exhibit text visible in the background.

Side-by-side illustration comparing a modern black-and-white bird on the left with a feathered dinosaur, Archaeopteryx, on the right, both with wings spread.

The video thumbnail image shows an illustration of the bird dinosaur Longipteryx alongside two toy dinosaur figurines.

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Topics

law of faunal succession fossil biostratigraphic unit paleontology index fossil catastrophism life geochronology dating evolution cell Metabolism heredity death Biology coloration photosynthesis Sex

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Key People

Charles Darwin

Charles Darwin

British naturalist

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Per Teodor Cleve

Swedish chemist

Cross section of Earth showing the core, mantle, and crust

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