What is an orange?
The world of citrus fruit is an incestuous one.
I had long wondered what the difference is between a mandarin, clementine, satsuma and tangerine. It turns out that the answer is: ‘bad question’; clementines, satsumas and tangerines are all varieties of mandarin. Looking a little further into the convoluted family tree of the citrus fruit reveals a pretty complicated soap opera style mess of relationships, with most of the common fruits we enjoy being hybrids of other, more unusual ones.
To try and make sense of the mess I made the above ‘Citrus venn diagram’ to try and illustrate the relationships between fruit. Each circle represents a variety of citrus and those contained where others overlap signify hybrids of the two.
For example: a grapefruit is a cross between a pomelo and an orange (which is itself a cross between a pomelo and a mandarin).
It’s a rough representation, I’m not making any distinction between species and cultivars (or even a sub-genus like papeda) but at least I finally understand how mandarins, clementines, satsumas and tangerines all relate to each other. There are many more hybrids out there, but I tried to include only the more common varieties. In fact the ongoing search for a better citrus seems to be an important scientific endeavour, there is even a research centre dedicated to the exploration of citrus located, of course, in Florida.
UPDATE: You can download a higher resolution versions here.
(all data was sourced from Wikipedia)