AP BIOLOGY

Detailed explanation-1: -Fossils are the remains or traces of ancient life that have been preserved by natural processes. Examples of fossil include shells, bones, stone imprints of animals or microbes, exoskeletons, objects preserved in amber, petrified wood, coal, hair, oil, and DNA remnants.

Detailed explanation-2: -What is a fossil? Fossils are the preserved remains of plants and animals whose bodies were buried in sediments, such as sand and mud, under ancient seas, lakes and rivers. Fossils also include any preserved trace of life that is typically more than 10 000 years old.

Detailed explanation-3: -Body Fossils and Trace Fossils The fossils of bones, teeth, and shells are called body fossils. Most dinosaur fossils are collections of body fossils. Trace fossils are rocks that have preserved evidence of biological activity. They are not fossilized remains, just the traces of organisms.

Detailed explanation-4: -Fossils are preserved by three main methods: unaltered soft or hard parts, altered hard parts, and trace fossils. You already learned about trace fossils in Chapter 4. Unaltered fossils are rare except as captured in amber, trapped in tar, dried out, or frozen as a preserved wooly mammoth.

Detailed explanation-5: -Fossils are the geologically altered remains of a once-living organism and/or its behaviour. There are two main types: body fossils represent all or part of the organism’s body, and trace fossils show evidence of the organism’s behaviour.