QUOTE from THE RISE OF YEAST

"Yeast fell into its intimate relationship with alcohol after an abnormal act of copulation. Around 100 million years ago, when pterosaurs wheeled in the skies, a couple of yeast cells that had been budding in tree sap nudged against each other and mated. this liaison caused a genetic eruption called a whole genome duplication. Offspring produced from normal mating reactions have the same number of genes as either of their parents. in this instance, infant sugar fungi were born with double the number of genes: 10 000 instructions coded in the DNA of each cell rather than the usual 5000 gene recipe for making yeast."
The Rise of Yeast: How the Sugar Fungus Shaped Civilization  - Nicholas P. Money

Nicholas P. Money in The Rise of Yeast:  How the Sugar Fungus Shaped Civilization (2018)