GIVING EXAMPLES GIVE AN ACCOUNT OF THE EVIDENCES OF ORGANIC EVOLUTION. (20MKS

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Giving examples give an account of the evidences of organic evolution. (20mks)

          Comparative anatomy
Comparisons of structures of different organism show resemblances in structure and functions.  E.g. Digestive systems;
Homologous structures; like pentadactyl limb; have similar origins but perform different functions showing divergent evolution or adaptive radiation.
Invertebrates have similar structures that perform different functions; showing common ancestry;
Analogous structures; are morphologically different but perform similar functions; showing convergent in Evolution;

Comparative embryology;
Embryos of vertebrates have great similarity showing common ancestry; e.g. the long thin shape and other body systems;

Cell biology; Comparative serology; 
Cells from different organism have similarity in structure; and functioning; closely related animals have similar plasma proteins; suggesting common origin;

Geographical distribution and continental drift;
Organisms originated from a common dispersal centre when the continents were joined; continental drift occurred isolating the organisms bring different patterns of evolution due to adaptive radiation; e.g. the Galapagos finches.

Taxonomy;
Classification based on Evolutionary relationship show great  similarity in organism of  the same Taxa ; e.g. phylum having less common features while species have the highest common features.
[20mks]

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