The shift from the Miocene, which had greater diversity of ape species and fewer monkey species, to a living assemblage with greater diversity of monkey species and fewer ape species may be the result of .

A differential ability to exploit habitats after global climate change

Explanation:

According to the evolutionary theory proposed by Darwin (1859), it is not the strongest nor the most intelligent who survive, but those that are most adaptable to change. The animals that disappeared during the Miocene, a geological epoch from around 23 million years ago to 5 million years ago, likely failed to adapt to changes in environmental (temperature and vegetation) conditions. During this epoch (Miocene), a more severe climate and coarser vegetation likely contributed to the extinction of several mammal species (e.g., species of apes) and diversification of others (e.g., the divergence between chimpanzee and hominid lineages).