How interesting – both of us jumped to a conclusion about how geographers “usually” define North America, without any hard data to back up that claim. It’s just common knowledge, in both cases, depending on whatever we’ve heard over the years in our respective regions.
In the U.S., we’re taught that the Isthmus of Panama is the boundary between the two continents. In part that’s because the Panama Canal cuts across it, joining the waters of the Atlantic and Pacific. Of course, that isn’t unique to the Panama Canal. Few students are ever taught about the other waterway connections closer to home.
Or we learn about how the Darién Gap interrupts the Pan-American Highway, not that many here would dream of traversing the entire highway, but we hear about the gap increasingly often in the context of northward migration. Or we’re shown an animation of the Isthmus of Panama developing as the final portion of a land bridge between two continents.
By contrast, practically no one up here has ever heard of the Isthmus of Tehuantepec, but having heard of it, no one would dispute its narrowness. Is narrowness the sole, deterministic criterion for partitioning the Americas? Or is it just one of several convenient approaches? Plenty of maps delineate the two continents at the Colombia–Panama boundary or the Guatemala–Mexico boundary, as Geofabrik does, even though a political boundary is clearly irrelevant to physical features.
All of this is very interesting, but ultimately irrelevant if we map all three continents as a compromise and continue to represent them as simple nodes.
