[AOE:DE] What am I supposed to do once the world runs out of resources?

The wood is gone, the stone is gone, the gold is gone. Soon I won't be able to make farms, or even fish. My people will starve and I can only make axemen until then. In Age of Mythology and 2 I remember that some food sources were infinite, and I could sell food for other resources at the market. Am I simply out of options? What can I do?