BBC's Misha Glenny and guests discuss the exchange of cultures and biology across the Atlantic and Pacific after 1492. That was when Columbus reached the Bahamas, a time when Europe had no potatoes, tomatoes, sunflowers or, arguably, syphilis in its most virulent form; the Americas had no cattle, bananas, sugar cane or smallpox.
The lists of what was then exchanged are long and as these flora, fauna and diseases moved between continents, their impact ranged from transformation to devastation. In parts of the Americas, European viruses helped kill over 90 percent of the population. In parts of Europe, Africa and Asia populations boomed on the new American foods. Sheep from Europe grazed fertile land into deserts in some parts of the Americas, while the lowered populations in others led to local reforestation which, arguably, is linked to a particularly cold period in the Little Ice Age.
