How do blood oranges turn red? And what does that have to do with the climate?

This Video is my contribution to the Fast Forward Science competition 2022/22 #FFSci #scientistaward. More information at www.fastforwardscience.de.
Blood oranges differ from other oranges in that they produce anthocyanins. However, they only do this under very specific conditions, namely when it is cold. In order to get a beautiful red color, the fruits need very specific climatic conditions with cold nights during their ripening period. Because the cold activates a retrotransposon, a small parasitic genetic element, which also activates the anthocyanin production.
Here is a link to the google form to record your blood orange observations: docs.google.co...
Open access paper about Ruby in blood oranges: academic.oup.c...
More about transposons in plant genomes: www.pflanzenfo...
www.pflanzenfo...
www.sciencedir...
And more from and about Barbara McClintock:
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