The next Nobel Prize in Economics will be in the realization that all trade from all time was cultural. That the direct or indirect exchanges of all goods and services was to reaffirm cultural desires. It was never about money - money was just a measured reflection of what successful merchants considered culture moving backward from this date. From this realization onwards, the only purpose of economics was acknowledged as but one measurement of culture: the god particle of markets. That GDP existed alone to measure culture. That the pulse and conditions of culture would dictate the market for all trade.
That to understand the culture market was now a faster route than the money market.
Was to understand the additive effects of clashing cultures and was akin to financial forecasting.
Was to find the value created in the environments where cultures collided was manifest.
Edge effects occur in the intersection of two cultures. Its sequitur is that this intersection will contain the most diversity, more so than either culture. In ecology, these exist as valleys, fjords, islands, areas with a mixing of ocean currents or air currents, migration paths for animals. In culture, edge effects occur as major trade routes, ports and cities, emigration and exploration vectors. As people encounter each other in these edge areas they discover new methods and mindsets for what are universal activities. They trade cultures, they exchange their portfolio, they diversify a phenotype.
Understanding this exchange, culture can be seen as the impetus of all interaction.