Most of the books and texts we read during our learning on topics related to genetics and evolution describe genetic variation as “the raw material for evolution”. This statement is accurate; however, in this chapter, we will explore this topic and its definitions in greater depth to better understand its applications. We will explore a few key questions: why is genetic diversity necessary for a neotropical species? What is the importance of genetic variation for the use and domestication of genetic resources? Why do we need to conserve existing genetic diversity? Genetic diversity is generally higher in neotropical regions than in other areas on our planet. This makes sense as in this region we also have a wide range of environments variation (altitudes, temperatures, soil types, salinity, among others). The interaction between genetic and environmental variation results in more adapted phenotypes or phenotypes with greater potential for use by humans. However, other aspects of genetic variation, such as epigenetics, influence rapid adaptation, a process that we will address in this chapter.