What do you mean by organic evolution?
What do you mean by organic evolution? Answer
The basic similarities in chemical and structural organization of all organisms as stated above, exclude the “Spontaneous Generation” and “Special Creation” theories from the list of acceptable explanations for diversity of “Life” upon earth. Moreover, these similarities imply origin of all diverse forms of organisms from a common ancestor. Like the concepts of “Cosmic” and “Chemical” evolutions, therefore, the concept of “Organic Evolution” is now universally accepted as an explanation for the origin of all diverse forms of “life” from the first primordial organisms that arinert matter’ upon primitive ‘earth.
Let us consider, for a while, the order and grading we can witness amongst the existing varieties of organisms themselves. We know that animals and plants are organisms of two very distinct categories, yet the distinction between these at the primitive, unicellular level of organization is so little that a common “kingdom Protista” has been proposed to include all unicellular animals and plants together. Similarly, we know that such diverse forms as houseflies, ants, mosquitoes, louse, bedbugs, grasshoppers, butterflies, etc., are all included into a common group “The Insecta”. Likewise, the fishes, frogs, lizards, birds and mammals form a common group, “The Vertebrata” in spite of their pronounced diversity.. All this order and grading proves a gradual “Organic Evolution” of diverse varieties of organisms from common ancestors at different levels.
BASIC IDEA OF ORGANIC EVOLUTION
“Descent with change or mod is the basic idea of “Organic Evolution”.
Literally, the term ‘Evolution’ means “Unrolling or unfolding to reveal modifications (e out + volvere to roll)”. We know that the present models of our cycles, cars, aeroplanes, rail engines, watches and other machines have emerged as a result of constant improvements upon their original and previous models in accordance with peoples’ requirements. Similarly, evolution briefly means that, generation after generation, offsprings of a species modify in accordance with environmental requirements and, by accumulation of these modifications through a long series of generations, turn into better organized and more complex new species. Thus, each present-day species has descended or ‘evolved’ from a simpler ancestral variety by gradual modifications accumulating through successive generations.
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