Kehafossiile

Kehafossiile, also known as body fossils, are the preserved remains of an organism's actual body or parts of its body. This contrasts with trace fossils, which are impressions left by an organism's activity. Kehafossiile can include a wide range of preserved materials such as bones, teeth, shells, exoskeletons, and even softer tissues like skin or feathers in exceptional circumstances.

The preservation of kehafossiile typically occurs when an organism dies and is rapidly buried by sediment, such as mud, sand, or volcanic ash. This burial protects the remains from decomposition by scavengers and environmental factors like weathering and erosion. Over vast geological timescales, minerals in the surrounding sediment can infiltrate the organic material, replacing it or encasing it, leading to fossilization.

Different types of preservation exist for kehafossiile. Permineralization is common, where dissolved minerals precipitate into the porous spaces of bone or shell. Replacement occurs when the original material is completely substituted by minerals. Unaltered remains, where the original material is largely preserved, are rarer and often found in environments like ice, amber, or very dry conditions. The study of kehafossiile provides invaluable insights into the anatomy, physiology, behavior, and evolutionary history of past life forms.