But what apes.
To big for chimps and too small for gorillas (in fact gorillas are their enemy).
Philip Jose farmer suggests they were cavemen, throw backs to a much primitive time.
The fact is that ERB never really saw a gorilla or a chimp outside of a zoo. He relied on the tales of adventurers and game hunters.
So the beasts that tolerated Tarzan as he grew (only Kala raised him)were ERB apes alone, creatures of imagination, powerful brutes but family creatures. inteligent enough for leaders and councils, clubs and drums but still beasts.
Thats how i love them, not categorised as a creature we know, just similar to one.
Tarzan is as much fantasy as John carter and for that he needs his imaginitive world.
A world where Kong exists and atlantis sank beneath the waves and Ayesha lives eternal waiting the return of her love.