I came from a rural background, so I always sort of knew. The problem was keeping donkeys and mules straight. The only way I could remember was by reminding myself that mules are the ones that are stubborn, so, too stubborn to breed, except sometimes too stubborn to know they can’t breed…well, it worked for me as a memory aid.
Anyway, I wasn’t the only one who had trouble remembering, maybe because horses were a luxury and neither donkeys nor mules were common in these parts. In high school I was on the scholastic bowl team, and since there was no such thing as, say, Class M scholastic bowl, we were constantly ending up playing schools several times larger where one actually had to try out for scholastic bowl. So one day we had journeyed a considerable distance to a semi-metropolitan area for a tournament, fulling expecting to come in last as usual, when a minor miracle occurred and there was actually a question we had hope of being able to answer first.
This question was, “What is the only animal unable to reproduce?” (Yes, I know, there is more than one, but obviously they meant the most obvious.)
Our team leader hit the buzzer and blurted out, “The donkey!” As soon as he said it, he knew he’d made the wrong equine choice. What’s more, he had just handed the answer over to the other side, because, duh, if it’s not the donkey it must be the mule.
To our surprise, the other team, not farm kids, sat there in complete puzzlement, shaking their heads. We could hear some of them muttering, “All animals can reproduce…”
We lost the game anyway. We came in second-to-last at the tournament that day, which I believe was our highest finish that year. We were so excited we never did ask how we managed that feat when we had lost every game that day.