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Seedless. Nutritious. Portable. Tasty. Yellow. You pretty much know what you're going to get with a banana. And you should get it before it's gone.
Bananas -- or more accurately, the Cavendish, a specific type of banana that most of us consider to be "the" banana -- are an incredibly consistent fruit. There's a reason for that. All Cavendish bananas are clones, and therefore genetically identical to every other Cavendish out there. (It's not uncommon for fruits to be cloned. Navel oranges are also clones, for example.) And being clones has a big downside -- if there's a disease that affects one Cavendish, it affects all Cavendish.
Which is why the bananas most people eat -- and we eat a lot of them, over 25 pounds of bananas per American each year (that's the most of any fresh fruit!) -- aren't the same bananas that were eaten 50 years ago.
Prior to 1960, the standard commercial banana type was the Gros Michel (aka "Big Mike"), a larger banana type that, by many accounts, was also tastier. But the Gros Michel was susceptible to Panama disease, caused by a fungus that attacked the roots of banana plants. Panama disease spread rapidly through major banana plantations, crippling businesses and making Gros Michel cultivation commercially impossible. After billions of dollars of research and development, the Cavendish -- which is genetically resistant to Panama disease -- became the world's top banana.
Could the Cavendish go the way of the dodo and the Gros Michel? Absolutely. A relatively new strain of Panama disease, Tropical Race 4 ("TR4"), can destroy Cavendish crops, and the only known way to stop it is genetic resistance, which the Cavendish (being a clone) won't ever develop. TR4 has already attacked banana plantations in Australia, Taiwan, Malaysia, Indonesia, and has spread to Southeast Asia. Experts believe that it is only a matter of time, perhaps decades, before TR4 sends the Cavendish down the same path as Big Mike.