Final answer:
Africa holds the greatest genetic diversity due to its status as the cradle of human lineage and the subsequent environmental, dietary, and climate adaptations that have occurred over a longer period compared to other continents.
Step-by-step explanation:
The continent with the greatest genetic diversity is Africa. This is attributed to the fact that humans have most likely descended from Africa, and consequently, the genetic variation in Africa serves as a repository for the earliest human genetic lineage.
As discussed in Chapter 4, the longer a population has existed, the more time there has been for mutations to occur, leading to a wider range of genetic adaptations and variations. This is why the genetic variance within the African continent is greater than in the rest of the world.
The Out of Africa model supports this idea and is backed up by genomics evidence that indicates all non-African human genomes are closely related to those found in Africa.
Additionally, the study of coevolution between humans and lice provides insights into human evolution and supports the fact that human diversity has been shaped by a variety of factors including environment, diet, and climate variability.