Question

How do fossils indicate that the Earth might be very old?

Answer 1

Hint: Fossils are nothing but any traces or any impression of the living organisms that left on the earth after their extinction, and some of the examples for the fossils are skeletons, some stones, and shells, and some imprints of the animals and plants, and the study of the fossils is called as paleontology.

Complete answer:
Paleontology is the study of fossils which includes the types of fossils, formation, and age of the fossils and their evolutionary significance.
Fossils that are found on the earth indicate previous living organisms and they are of various types when coming to the size, they are of small microorganisms to dinosaurs, and they also include the big and old trees which are many meters long and they weigh many tons.
Fossils do not mean the complete organism, it may be a small portion of the deceased organism, where the portion which we generally considered as fossils now are the ones which are mineralized during their life such as bones and teeth of vertebrates.
Fossils may also consist of marks that are left behind the organism while they are alive, such as animal tracks or feces.
These type of fossils are called trace fossils that are opposite to that of body fossils whereas some fossils which are biochemical and those fossils are called chemo fossils.
Fossilization includes a lot of processes where they have several steps that are pre mineralization, followed by Authigenic mineralization, and then a replacement, recrystallization, and adpression, carbonization, bioimmuration.
This process shows long long back animals and organisms that formed very early on the earth, so these fossils indicate that the earth is very old.

Note: Fossils are the part of old living organisms that are extinct, remain on the earth, as were the mineralized parts of the organisms such as skeletons, teeth, shells, and woods of the plants and stones and even microbes.