THE PROCESS OF FOSSILIZATION AND THE IT’S SIGNIFICANCE IN THE INTERPRETATION OF THE EVOLUTIONARY EVENTS.

Fossils refer to the remains of plants and animals that existed many or long time ago and it is mostly occurring in sedimentary rocks and the process of fossilization occurs when living organisms such as animals and plants dies. This process of fossilization mostly occurs near the river where there is a lot of sand. Fossilization mostly occurs on big organisms that have hard body parts such as bones, teeth, clews and shells. It is impossible for small animals to be fossilised because they have a soft bodies and they do not live for the long time, so they can became extinct.


When the animals died, their meat is eaten by their enemy or predators and leaves their bones. "These bones will be left untouched, and when the wind blows the sand and sediments, these bones will be covered and place underground. The organism must be covered by sediment soon after they died or decaying process and the sediments will continue cover up the bones until they are hidden far underneath the ground. After they have been covered with sediment they become solid and they will be covered into rock and organic remains replaced with a minerals and it is called diagenesis form" (Wikipedia contributors, 2006).


During the process of fossilization "minerals, calciums and hydroxyapatite found in the bones replace by the minerals that are found in the sand and after many years, and there will be a lack of an organic materials in the bones because they will turn to solid rock and end up to being a fossils. There are two types of fossils, namely: organic fossils which were once part of living organism and trace fossils which are the trackways, burrows, footprints, eggshells, nests and worms holes" (Wikipedia contributors, 2006).


The fossils of small animals such as insects, spider, and small lizards can be found in "the mud stone or sandstone and psedofossills are produced by natural occurring in the geological process and same of these fossils such as dendrites are formed by naturally occurring in the rock that filled up with the percolated minerals. Other examples of the psedofossils are kidney ore and moss agaster" (Wikipedia contributors, 2006).


The reef-building corals fossils show that "the rocks were deposited in warm and were found in the tropical seas where sunlight can pass through the water to reach the their photosynthesising algae within their cells. Fossils may be formed close to the edge of the body of water. The Koonwarra fossil includes fossilised fish, plants, insects spiders and bird feathers. These fossils show that the deposit was formed in the dip part of the large freshwater lake because the insets are living in cool mountain streams and in lakes. These insects were not transported far after their death"(Wikipedia contributors, 2006).


Most of the fossils are found in the sedimentary rocks that have been formed by the consolidation of the soft sedimentary such as sand and mud. Fossils which are found in igneous rocks are hidden from a molten state or in the metamorphic rocks that have undergone intense pressure and heat. The fossils occur in sediments such as rocks, and incorporated as an integral part of the rock formation. Unconsolidated sediments such as sand or muds are good for burial. The other thing is that fossilization is the process of the hard part of the skeletons and shells etc and these were fossilized under high favourable conditions.


References:

1.Wikipedia contributors. Fossilization [internet]. Wikipedia, The Free Encyclopedia; 2006 May 4, 13:36 UCT [cited 2006 May 8] available from:
http://en.wikipedia.org/wiki/fossils

2. Fossilisation [Internet ] Wikipedia [cited 2006 May 03] Availabe from: http://www.museum.vic.gov.dinosaurs/sci-form.html



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