As I have pointed out many times, there are no fossil humans or fossil gorillas in Miocene rocks, although Miocene rocks contain many fossils of other species of apes (e.g. Proconsul, Kenyapithecus, Dryopithecus, Oreopithcus, Graecopithecus, and Samburupithecus). Obviously modern humans and modern gorillas must have had Miocene ancestors, and the obvious inference is that these ancestors were some of the extinct species of apes whose fossil remains are found in Miocene rocks. In other words, these Miocene apes did not remain Proconsul, Kenyapithecus, Dryopithecus, etc; instead, they evolved into new species, some of them the modern apes and humans. What other explanation can you offer for these observed facts?
You say that gorillas stay gorillas and humans stay humans. Did Australopithecus afarensis, Australopithecus africanus and Australopithecus sediba stay the same species, and if so, why are they not still living in Africa? Present the evidence for your answer.