Chapter 1 talked about how variation in domestic animals exists and how it led to the existence of new domesticated species. Chapter 2 does the same for variation under Nature.

Most of this chapter deals with the difference between variations and species.

It also mentions how these variations are caused by physical conditions and competition across different organisms.

It also talks about fruitful variation being passed down to offsprings and creating species that dominate a given environment.

Leading to the conclusion same as for domesticated animals that variations lead to the existence of distinct species.