EXPLAIN THE DIFFERENT EVIDENCES OF EVOLUTION (20 MARKS)

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 Explain the different evidences of evolution  (20 marks)

Comparative anatomy and taxonomy;
Members of a phylum or group show similarities; organisms have structures or organs performing the same function ; e.g. digestive system ; nervous system same function etc (any correct example 1mk)
The pentadactyl limb (any correct example); these are called homologous organs or structures; homologous- same origin but have different function;  
Analogous structures or different structures performing the same function e.g. wings of insects, bat and birds; Analogous – different origin but performing same function;

Fossil records / Paleontology; 
Remains of organisms preserved in naturally occurring materials for many years; show morphological changes of organisms over a long period of time; e.g. skull of man, leg of horse 

Comparative embryology; 
Embryos of vertebrates have similar morphology; suggesting the organisms have a common origin or ancestry ;

Geographical distribution; 
Continents present are thought to have been a single large landmass; joined together; as a result of continental drift; isolation; occurred bringing about different patterns of evolution; e.g. ilamas in the amazons resemble the camel /any other correct example e.g. kangaroo in Australia Jaguar in S. America; camel in Africa;

Comparative serology/physiology ; 
Antigen–antibody reactions/RH factor/blood groups/haemoglobin structure reveal some phylogenetic relationship among organisms/common ancestry.

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