Macroevolution: Charles Darwin's Theory Of Evolution

Evolution is the theory that all living forms came from ancient ancestors. Through a series of mutations, genetic drift, migration, and natural selection today’s descendants show an amazing amount of similarities and diversity. Evolution on a small scale is called microevolution, relating to the changes that occur such as insects becoming resistant to pesticides. Macroevolution refers to the grand scale. It is associated with extinction, change, stability, and lineage. At the time of its “birth”, it was a controversial subject. Charles Darwin was the first to formalize the theory of evolution, but before him there were more scientists interested in it.

Charles Darwin was born in England and originally planned to take up a career in medicine.

Instead of focusing on a single branch, macroevolution focuses on that chunk of the tree. It identifies patterns and transformations, then figures out how and why it happened. Mutation, migration, genetic drift, and natural selection are basic mechanisms that apply to both micro- and macroevolution to determine these patterns.For 3.8 billion years mutations have been passing through the filter of natural selection, creating stronger and more resilient descendants. Changes and extinctions that have happened over the years are all part of macroevolution. Some changes take place slowly, this is called stasis. An example of this is the cœlacanth, a fish hauled onto a ship in 1938, it was thought to be extinct for 70 million years. Extinction is an important part of evolution. Every species has a chance that it will become extinct. Microevolution is an even more important part of the evolutionary theory. As previously discussed, it is evolution on a small scale. It is the changes in animals to adapt to their habitats and the changing environment. Microevolutionairy changes can be seen by changes in gene frequency. A few of the mechanisms that affect these changes are mutation, migration, genetic drift, and natural selection. If a random cell is mutated, for example if a yellow bird has some purple chicks and the rest are yellow. The genes in the yellow bird would have been mutated to produce purple chicks. If the purple chicks moved to another island, and the yellow birds on that island immigrated to the island that purple birds had previously inhabited, that is known at migration, or gene flow. When a mutated gene is passed to more offspring and out numbers the original colored offspring it is called genetic drift. As for natural selection, it means that the more well equipped animals are the most likely to survive. For example if the purple birds lived in a purple tree they would be more likely to survive than their