A fossil is evidence of past life found in a rock or other materials.
             A fossil is the remains of an animal or plant that has been preserved in rock and other materials, and it's the evidence of past life.
             c) In rare case only, a complete animal may be preserved, as: an insect trapped in
             Fossils can be created when the remains of animal or plant are covered by sediments (dust, sand or mud) and become part of the sedimentary rock that is formed.
             Index fossils: Fossils that lived over a comparatively short period of time and were widespread and can help determine the age of layer of rock.
             a) An ammonite dies and falls to the bottom of the sea where it's covered by sediments and
             protected from being eating by other animals. The soft part of its body decay,
             b) More and more sediment covers and squeezed the shell. The shell may remain or be
             replaced with minerals such as quartz or limestone that seep into it in solution
             before the original shell dissolves.
             c) After millions of years, movements in the earth's crust may thirst the layer of
             sedimentary rock containing the fossils upwards to form part of a mountain range.
             d) Weathering and erosion may eventually wear away some of the rock to expose part
             of the fossil. Fossils are often found in road cutting or quarries.
             Q1: Are fossils the real bones and shells of dead animals?
             A1: No, almost never. Usually, over a long period of time, the plant or animal absorbed
             minerals from the rock around it and this makes it turn hard and preserved it. So,
             fossils are rock that is molded like bones. Actually, a fossil can be a footprint,
             animal dung, a piece of plant, or animal bone - all kinds of things.
             Q2: Are there fossils in the earth of all the trillions of animals that ever lived?
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