Gone Bananas

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 which most of us consider to be “the” banana — if nothing else, 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 which can affect one Cavendish, it effects 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 which, by many accounts, was also tastier.  But the Gros Michel was susceptible to Panama disease, caused by a fungus which 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.

Bonus fact:  Bananas are radioactive.  Specifically, the potassium they contain is actually a rare radioactive isotope thereof.   The radiation is at low enough levels where it is not very dangerous, to say the least: eating 2,000 bananas will have the same toll one your lifespan as smoking one and a half cigarettes, per Wikipedia.  That said, the amount of radioactivity is real and measurable, so much so that bananas have been known to set off false alarms at U.S. ports looking for smugglers of nuclear materials.

From the Archives: Navel Oranges: The Mutant Clones in Your Kitchen: Navel oranges also have an interesting history.

Related: Want to be a radioactive banana next Halloween?  Heres’ An adult-sized banana costume.  Uranium sold separately.