Over the weekend, I stumbled over a great Damn Interesting post about the history and future of the banana. Some of you already know the basic story here: Bananas, as we know them, cannot reproduce. The ones we eat are sterile hybrids. Like mules. The only way that there are more bananas is that humans take offshoots from the stems of existing banana trees, transplant them, and allow them to grow into a tree of their own. It's basically a cheap, low-tech version of cloning, and it has a long history in agriculture. (Note: This would be why Christian evangelist Ray Comfort's video on bananas has become a classic Internet LOL. In the video, Comfort presents the banana—particularly its seedless flesh, handy shape, and easy-access peel&mash;as a testament to the perfection of supernatural design ... completely ignoring the fact that all those things are the result of human-directed agricultural selection.)
The downside to this is that clones are, shall we say, not terribly genetically diverse. Turns out, a lack of genetic diversity is a great way to make yourself vulnerable to disease. Back in the 1950s, a fungus all but wiped out a variety of banana called the Gros Michael. Up until then, the Gros Michel had been the top-selling banana in the world. It was the banana your grandparents ate. You eat the Cavendish, a different variety that replaced Gros Michael largely on the strength of its resistance to the killer fungus.