Discuss the various evidences which show that evolution has taken place.(20mrk)

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Comparative anatomy / taxonomyMembers of the phylum / group / show similarities; organisms have similar structures / similar organs performing same functions e.g. digestive system, urinary system, nervous system/ appendix/ coccyx/ vesceval/ heart/the pentadactyl limb, / any correct example. These are called homologous structures same in origin different functions e.g wings of insects, bats and birds;- Divergent evolution; Analogous structures- different in origin same functions; leading to convergent evolution 8mks. Max. (5mks)
Fossils records / PalaentologyThese are remains of organisms preserved in naturally occurring materials; for many years; shows morphological changes of organisms over a long period of time; e.g skull of man/leg of horse; (4mks)
Comparative embryologyEmbryos of vertebrates which are morphologically similar; suggesting organisms have a common origin / ancestry; (3mks)
Geographical distributionPresent continents are thought to have been a large land mass; as a result of continental drift; Isolation occurred; bringing different patterns of evolution; e.g Thus in Africa .This resulted into formation of new species; (5mks)
Comparative serology;Antigen- Antibody reactions / rhesus factor / blood group/ haemoglobin structure occur in oyster reveal some (phylogenetic) relationship among organism / common ancestry. (3mks)

Total (20 mrks)

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