A warmup question? How is Persimmon like cacao? If you said “they both need to ferment,” you’re in good company. But the truth is that they are both considered food of the gods. Persimmon’s species name is Diospyros, while cacao’s is Theobroma. Dios pyros translates as fruit of the gods, literally “the wheat of Zeus”. Theo broma, likewise, is the food of the gods. Both Greek. [1]
On the jujube, like many others who stumble late onto the wonders of odd edible species, I had for the most part assumed it was some kind of long-lost trade name for a suckable sweet, a throat lozenge, if you will. In fact the jujube (or, as Vavilov would have it, the ju-ju) is the fruit of the jujube tree, known these days as Ziziphus zizyphus. Vavilov called it Zizyphus jujube, which indeed it was until 1882. In that year, the tree became Ziziphus zizyphus officially.
Tautonyms (genus=species) are permitted in zoology (from Alces alces to Zungaro zungaro) but they are forbidden in botany. How, then, did Ziziphus zizyphus get accepted?
The eagle-eyed among you will have spotted that the genus is spelled with an i, while the specific epithet is spelled with a y. Why?
I didn’t know, but I found out by reading The Evil Fruit Lord’s blog post on the subject.
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 … in 1882 the name was changed to Ziziphus zizyphus.
So much to learn, so little time.
Notes:- Of course, what I really would like is for a genuine scholar to explain this better. [↩]
{ 4 comments… read them below or add one }
I always thought that Diospyros meant “divine fire” – looks like I was wrong.
There’s a proposal that’s been submitted to maintain Ziziphus jujuba, but a decision doesn’t appear to have been published yet.
“Ziziphus zizyphus” is apparently a “paratautonym”. There’s a word I will never use in conversation.
I would guess that the “pyros” of Diospyros and “Pyrus”, as in pear, probably come from a common root?
Looks like zizi-fruit has reached Australia: http://www.fructidor.com/news/innovative-farmer-takes-a-chance-on-chinese-date-also-called-zizi-fruit–5872.aspx