macrofossil

Macrofossil refers to fossilized remains of organisms large enough to be seen with the naked eye, typically exceeding a few millimeters in size. Macrofossils contrast with microfossils, which require magnification. They include bones, teeth, shells, wood, leaves, stems, seeds, and imprints of soft tissues or tracks. They form when biological material is buried and preserved by permineralization, replacement, carbonization, casting or compression, or fossilizable in amber or ice. Macrofossils provide direct morphological and anatomical information, enabling taxonomic identification and reconstruction of ancient life, behavior, and ecosystems.

Depositional contexts such as sedimentary rocks, peat, and amber produce macrofossils. Dating relies on the surrounding stratigraphy for relative ages, while radiometric methods or associated index fossils can yield absolute ages. The record is biased toward organisms with hard parts and favorable preservation conditions, and many environments yield incomplete or distorted remains due to taphonomic processes.

Major uses include biostratigraphy, paleoecology, and paleoclimatology. Well-known macrofossil records include dinosaur bones and teeth, mammal teeth, fish skeletons, shelled invertebrates, plant impressions and fossil wood. In some cases, soft-tissue impressions or carbonaceous films provide limited insight into anatomy or coloration.

Excavation, preparation, and imaging (including CT scanning and microscopy) are standard methods to study macrofossils. Their study complements microfossil analysis to build a comprehensive view of past life and environments.