| Growth | Accelerated growth |
| Timeline | 2.5 million BC - present |
| Challenges | Political challenges • Conflicts |
| Urban centers | Massive urban centers • Trade hubs • Cultural exchange |
| Political entities | Unified but decentralized government |
| Alien relationships | Early collaboration • Unified government with decentralized control |
| Evolutionary history | Humans evolve with a longer evolutionary history |
| Culture and technology | Diverse cultures • Advanced technology |
