You may not know it. But your bananas have been under attack for more than a decade by a small fungus, Fusarium oxysporum. Half of the global production of bananas is in a variety called Cavendish which has become susceptible to a new strain of the fungus. A previous strain of Fusarium wiped out the Gros Michel variety of bananas which used to dominate world markets until the 1950s.
The Cavendish seemed immune to the previous strain and could therefore be planted on the same land—Fusarium lives in the soil—that the Gros Michel occupied. The Cavendish is what is mostly exported to countries that do not grow bananas and therefore what most people see in modern supermarkets and greengrocers. It is named after William Cavendish, the sixth Duke of Devonshire, who received a shipment from a friend who had gotten them from Mauritius. Cavendish's gardener proceeded to cultivate them in the duke's greenhouses.
If you are a banana eater, you may have noticed that the Cavendish you peel and eat every morning has no seeds. It turns out that the Cavendish is propagated by cloning—which means that Cavendish banana trees around the world are genetically identical. And so, every one of them will likely eventually succumb to the new strain of Fusarium as it spreads worldwide.