One's personality is both a composition and reflection, but if I have to choose one of them, I will choose reflection as the "self" is more important to me than "me". One's composition may change, walking across the cultural landscapes and climbing the social ladder but one's self is tied to one's reflections. The fun part is that reflections are not bound to "Time-Space" barriers ( it is not time-space) and respective mental constructs, which have grown so thick over ages, that they had reduced the image of humans to Sisyphus, rolling different sizes of boulders on hills of different heights.… As the name of this Blog indicates, knols are my perspectives on topics of interests, sweet/bitter experiences or just doodling :)

Monday, November 28, 2011

Redefining Fossils

The history of life is deeply embedded in history of earth and similarly the history of earth is embedded in the history of universe. So when we look to fossils as relicts and evidences of history we can't confine ourselves to the history of life only. (Even a biological fossil have clear aspects: 1- The morphology and sometimes anatomy of animals, plants or any other life forms preserved tell us the position of organisms in a clade or tree of life. 2- The biozone from where the fossil or fossils are found tell us about the geological age of the organism and 3- the sediments in which fossil is preserved tell us about the environment where organism was living or it has tried to live in ). If so is the case then we have to expand the definition of fossils to include physical, chemical and biological relicts under terms of fossils. Yes! for sake of specification we can put an adjective to specify our fossils. For example, Physical fossils, Chemical fossils and Biological fossils.
1. Physical fossils:
Physical fossils are used to determine the age of universe. As big bang produced, heat (radiation), sound (Shock waves), light and velocity so these four aspect of first explosion is used to look back into history of universe. The relict, light, velocity (distance), shock waves and radiations are physical fossils of universe.
Chemical Fossils:
Elements which are the base of the all chemical reactions, molecules and compounds are resulted in process of nucleosynthesis in the stars. Certainly this process still continues though Universe has lost its initial concentrated energy by expansion. Contrary to formation of elements in nucleosynthesis process in stars, there is a reverse process of breaking down of heavy nuclei into lighter daughter nuclei and hence creating new elements. This is known as decay of radioactive isotope. This reverse process is used in absolute dating or radiomatric dating by Scientists.
As radioactive isotopes has a constant rate of decay so they work as chemical fossils in determining age of rocks, minerals and even an organism in which they are scattered.
Biological Fossils:
Biological fossils are well known to all. Biological fossils are divided into several categories,
a. Macrofossils: Fossils that could be observed by naked eyes including famous massive fossils of Dinosaurs.
b. Microscopic fossils: Fossils of microscopic animals, unicellular organism and pollens and spores.
c. Biomarkers: The organic compounds or fragments of cells that could be related to their sources.

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