Diversity can mean a lot of things. In an ecosystem, diversity can refer to the number of different species or ecological niches that are present. Scaling things up, within a region, there can be a diversity of ecosystems. If we move down to the species level, genetic diversity is how much genetic variation there is in a population. Genetic diversity is important because the more genes are in a population, the more likely that one of those genes will prove helpful in the face of threats such as climate change or a new disease. Genetic diversity is related to the ability of a species to adapt to a changing environment