C1856 Origin of Rebirth(last Part)

In fact, there was always a question in the history of human evolution, which was, why did the ape appear 3 million years ago, and only walk in a semi-upright state, which lasted until 800,000 years ago, before being able to walk in full upright? In the history of human evolution, only this little bit of it evolved over 2 million years ago, but 40,000 years ago, human intelligence began to