Explain the theory of evolution and mention the proof supporting it
Ans :
Progressive development of plants and animal from the ancestors having different structural and functional organization is called evolution. According to the theory of evolution, first living material (protoplasm) has been formed in ocean. In due course of time, unicellular organism was formed. Gradually, changes occurred in the unicellular organisms from which larger and more complex organisms were formed. All those changes were slow and gradual. Duration of all these changes is at the most 300 crore years. Changes and development in living organisms had been all round and multi-dimensional and this let to evolution of different types of organisms. Hence, this overall process is called as evolution which is organizational. Collective thinking on the theory of evolution implies that it is an everlasting process of changes.
Following are the various proofs available in support of the theories -
1) Morphological Evidences - Similarities in superficial characters.
2) Anatomical Evidences - Similarities in bone structures.
3) Vestigial Organs - Degenerated or underdeveloped useless organs of organisms. Example: Tail bone (coccyx), Appendix, Wisdom teeth and Body hairs.
4) Paleontological Evidences - Study of fossils.
5) Connecting links - Plants and animals show some morphological characters by which they can be related to two different groups.
6) Embryological Evidences - Comparative study of embryonic developmental stages of various vertebrates.