diffusion theory rears its unattractive head again
I had to ditch Spivey because she had such screwy ideas. I'm a little concerned about Albala; in a summary of what Europeans were eating during the 1500-1800 time frame, he asserts that the pumpkin "may have arrived from Asia in classical times, or it may have come from the Americas." He also says that "the very fact that they could also be found as far away as China within a few years has led some scholars to suggest that they may have reached Asia even before they did Europe", regarding capsicum. And, "Perhaps more difficult to explain is the fact that corn was also grown as far as China by the early sixteenth century. This suggests that corn may have reached Asia from the Americas even before Columbus' encounter."
If he included any sources for any of these, it would be trivial to decide what to think of this. As it is, I'm just going to call bullshit and say, hey, pumpkins did _not_ arrive from Asia in classical times, and while Asians may have cultivated peppers and corn more quickly than Europeans, they did not lay hands on them any sooner than Columbus' first arrival in the New World. I don't have any trouble at all believing that Columbus might land a few times, and within the decade, China would be growing everything their spies could collects seeds. That sounds about right to me, anyway.