An adaptation that makes bipedalism possible is the need to get around. If your slithering on the ground, you could get diseases, or get hurt.
Answer:
Agricultural revolution, start of Neolithic era, maybe 12000 yrs ago
Explanation:
They might be going through the S Phase of the cell cycle which is DNA replication. Usually, when the cells go through this phase they end up to dividing.
Eukaryotic organisms contain translocation factors that are suited to perform the same function. A translocation that results in Tu being replaced with G or G being replaced with Tu will not affect the function of the protein.