I just came across an interesting tidbit on the nomenclature of the cultivated jujube (mostly on an obscure corner of the internet called Wikipedia...)
Ever since I learned the jujubes were actual fruit and not just a type of candy, I've been using Ziziphus jujube as the Latin name (now, granted, it's not like the Latin binomial for jujube comes up in my daily conversation that much). Well, apparently I'm a little bit behind the times, because the name seems to have been Ziziphus zizyphus since 1882.
I personally am so easily amused that this alone would be adequate to entertain me, but the story of how it wound up with that name is kind of interesting as well. In general, tautonyms (those in which the genus and species names are identical), while permitted in zoological nomenclature (hence Gorilla gorilla and Iguana iguana) are no good in botanical names. However, this one skated by on a technicality.
It was Mr. Taxonomy himself, Carolus Linnaeus, who gave the species its first modern binomial, Rhamnus zizyphus, placing it in the same genus as the buckthorns. However, in 1768 Philip Miller (a late and reluctant adopter of Linneaus' binomial system) decided it was sufficiently different to merit a separate genus, and gave it the name Ziziphus jujube. Why he changed it from a 'y' to an 'i' is unclear--it might well have been a typographical error. However, the arcane rules of taxonomy dictated that because Ziziphus and zizyphus were the first validly published and described names, and were not actually in violation of the tautonym rule thanks to the spelling difference, and thus the appropriate name, so in 1882 the name was changed to Ziziphus zizyphus.
And yes, I realize I'm probably one of about three people who found that interesting.