Which theory, developed by Darwin, explains the process of survival and reproduction of species?

The theory developed by Darwin that explains the process of survival and reproduction of species is natural selection. This concept posits that individuals within a species exhibit variation in their traits, and these variations can affect their ability to survive and reproduce in their environment. Those individuals with advantageous traits are more likely to survive and pass those traits on to their offspring. Over time, this leads to the adaptation of species to their environments, which can result in the emergence of new species. Natural selection is a foundational principle in the study of evolution and accounts for the diversity of life observed in nature. It illustrates how certain traits become more common in a population due to their advantages in survival and reproductive success.