WEIT 2012 Chap1

WHAT IS EVOLUTION

What is the definition of Evolution?

Evolution is a gradual process in which the biological populations change into a different and usually more complex or better form. Life on Earth began with a universal common ancestor. It changed gradually, taking several millions of years. This universal common ancestor, named LUCA (Last Universal Common Ancestor), branched out over time, throwing off many new and diverse species. This mechanism of evolutionary change is called natural selection. When you break that statement down, you find that it really consists of six components.

What are the six components?

The six components are evolution, gradualism, speciation, common ancestry, natural selection, and nonselective mechanisms of evolutionary change. Let see each of these components closer.

What is evolution?

Evolution is the fact that a species undergoes genetic change over time. The differences are based on the changes into the DNA. All the species evolve but not at the same rate.

What is nonselective mechanisms of evolutionary change?

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