Witnesses?
Your question doesn't really have all the information necessary to have an accurate answer.
The land was rugged containing Andes mountains, the coastline deserts, and the Amazon jungle. They eventually found solutions for their geographic problems. I hope this helps :)
Answer:
It reaches carrying capacity.
Explanation:
It can no longer carry for the lack of resources.
Roman Empire
The Fall of the Western Roman Empire (also called Fall of the Roman Empire or Fall of Rome) was the process of decline in the Western Roman Empire in which the Empire failed to enforce its rule, and its vast territory was divided into several successor polities.
Invasions by Barbarian tribes
The most straightforward theory for Western Rome's collapse pins the fall on a string of military losses sustained against outside forces. Rome had tangled with Germanic tribes for centuries, but by the 300s “barbarian” groups like the Goths had encroached beyond the Empire's borders
