16,500,000 years ago, Africa became arider as fluctuations in the climate caused a majority of the woodland environments to be replaced by open savannas. As a result, the ancestors of the Hominidae family, the greater apes, underwent speciation from the Hylobatidae family, the lesser apes, as the Hominoidea superfamily separated out into different species of hominids and gibbons.
16,000,000 years ago, hominids were beginning to use more and more elaborate systems of communication, although complex language did not yet exist. As time went on, they produced an array of sounds through the use of vocal organs as well as by way of chest-thumping, ground-slapping, and tree-drumming. Facial expressions, like teeth-baring, along with body postures also played an important role in this.
15,000,000 years ago, drier, more seasonal woodlands spread in eastern Africa so the distribution of fruits became less spatially and temporally abundant. As a consequence of this, leaves became the common dietary staple of the hominid populations that lived a million generations ago.
14,000,000 years ago, more and more primates in the Hominidae family began to leave the treetops and live on the ground, and they exhibited a greater range of sizes than that of modern apes. However, less hospitable cooler conditions in the Northern Hemisphere eventually caused many species to die out, although some hominids survived by migrating south.
13,500,000 years ago, Hominidae populations migrated to Southern Asia where the hominines eventually speciated from the ancestors of the orangutan. The Homininae comprised all of the extinct and extant species that arose after the split from Ponginae.
12,000,000 years ago, the diversity of hominids and hominines declined as the tropical and subtropical habitats of Europe and Asia began to contract and become concentrated closer to the equator as a result of tectonic forces.
10,500,000 years ago, as the hominines gave rise to hominins the descendants of the early apes diverged into two lineages, the gorillas and the line that…