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Evollution

One of the most popular explanations for evolution is micro and macro evolution. Micro evolution is changes within alleles and the genes of beings to promote survival within a small amount of time. These genetic changes can happen to bacteria or genes and result in phenotypic changes in an organism which may increase or decrease chances for survival. A good example of micro evolution is how bacteria develop antibiotic resistance. Germs, once they experience a certain antibiotic, can mutate, and then withstand that exact antibiotic. This explains why certain diseases can’t be cured at this time. But the bacteria itself micro evolved to survive the antibiotic.
Macro evolution is the change of entire gene pools over a long period of time.   Certain animals go through macro evolution, such as the finches, in order to survive in a new environment. Macro evolution also contains widespread phenotypic changes within a gene pool. An example, aside from the finches, is the Galapagos Island tortoises. The tortoises have certain shell shapes and neck lengths depending on the amount of vegetation the island got.   Islands with low vegetation have tortoises with a dome shaped shell and a short neck because the vegetation is easy to get to. And the island with higher vegetation has more of an opened shaped shell and a longer neck to be able to reach the food.
Another convincing piece of evidence for evolution concerns homologies, any resemblances between the anatomical, genetic or function of organisms. Anatomical homologous pairs are identified by comparing similar structures that serve a common function, while functional homologous pairs just concern the functions. Genetic homologous pairs are measured by comparing proteins or DNA sequences. Homology is very effective at suggesting a common ancestor that all species have evolved from. A human arm, a cat leg, a whale fin and a bat wing all homologous to each other because they are made up of the same type of bones: a humerus, an...