Fossils are the preserved remains, impressions, or traces of ancient life, offering a glimpse into the Earth’s distant past. They form when plants, animals, or other organisms are buried under sediment that protects them from decay. Over time, minerals seep in and replace or surround organic material, turning it into stone. The study of fossils helps scientists understand how life evolved and how environments shifted across geological eras.
There are several main types of fossils, each telling its own story about prehistoric life and environmental conditions. Some preserve the actual remains of once-living organisms, while others capture the imprints or activity those creatures left behind.
- Body Fossils – Preserved remains like bones, shells, or teeth; they show the organism’s physical structure.
- Cast and Mold Fossils – Impressions left in rock; a mold is the hollow imprint, while a cast is the filled-in form that creates a natural sculpture.
- Trace Fossils – Evidence of activity such as footprints, burrows, or nests, revealing how organisms moved or behaved.
- Petrified Fossils – Organic material replaced by minerals, turning wood or bone into stone while retaining texture and detail.
- Carbon Film Fossils – Thin layers of carbon residue left when soft tissues decay, often capturing plants or delicate creatures.
- Amber Fossils – Small organisms like insects preserved perfectly in hardened tree resin.