To know where it rightfully belongs to. Variation of certain traits is caused by multiple factors of an individual of the same kind. Depending on their physical appearance, their environment and nature of survival.
Hope this might help.
Answer:
Another evidence of evolution is the convergence of form in organisms that share similar environments.
Some scientists hypothesize that the eukaryotic cells are really the result of symbiotic processes!
Specifically, the internal organs of the cells could be a remnant of a symbiotic relationship in which one cell lived inside of another cell. These two cells then both split upon reproduction and eventually the cell inside was reduced to an organelle.
But according to this theory, it is very likely that the prokaryotic cells engaged in a number of symbiotic relationship, and that this actually lead to the emergence of eukaryotic cells!
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<span>Mutation
Adaptations are the result of evolution in different living organisms. This process occurs amazingly through gene mutation but it takes a very long period in time. Adaptation processes occur to help species survive and thrive in the ecological balance of life. Structural adaptations are physical features of an organism that adapted through time. An example of this are the bills of a bird and the fur of bears that they generally need for their survival; birds for hunting, and bears to protect them from low climate areas.</span>