What could an archeologist infer from the fact that fish bones have been found at mountain sites of the Inca Empire while potatoes a mountain crop have been found at coastal Inca sites?

The presence of fish bones at mountain sites suggests that fish were either transported from coastal areas to the mountains, or that the Inca people living in the mountains traded with coastal regions. The discovery of potatoes, a mountain crop, at coastal sites could indicate trade networks that allowed for the exchange of different types of produce between regions within the Inca Empire.