According to a research published in the journal Proceedings of the National Academy of Sciences mustard and wasabi came to have this flavor thanks to caterpillars. It seems that these creatures contributed to making plants produce chemicals which make these flavors delicious to humans.
It seems that about 90 million year ago the plants which were the ancestors of the Brassicale order of today found a way to protect themselves from hungry caterpillars. The Brassicale order includes mustard, wasabi and horseradish.
The ancestor plants started producing glucosinolates, which are sharp-tasting chemicals poisonous for caterpillars. However in time the caterpillars developed defense against the chemicals and continued feeding on the plants. So as a result the plants had to produce an even stronger poison.
Researchers say that this led to an evolutionary arms race. The new defensive adaptations of caterpillars made the plants produce more complex glucosinolates which were also sharper. And even though neither the plants nor the caterpillar won, humans were the ones who gained some benefits after this fight.
Lead author of the study biologist Chris Pires from the University of Missouri said that this is the reason why plants have flavors and are spicy. It was not meant for humans, but it is other reason behind it and that is evolution. Glucosinolates are present in almost half of the condiments used most often nowadays such as mustard, horseradish and wasabi.
It was already known that plants and caterpillars evolved together, but this is the first study to show how this actually happened. After analyzing how the cabbage butterfly and the Brassicales evolved researchers noted that instead of tweaking the already existing genes the “combatants” created fresh new copies of their genes and even entire genomes in some cases.
Professor Peter Raven of the Missouri Botaniacl Garden was not involved in the study, but he remarked that the study confirms existing theories about patters of co-evolution which were never really understood. He said:
“The wonderful array of molecular and other analytical tools applied now under leadership of people like Chris Pires, provide verification and new insights that couldn’t even have been imagined then.”
Pires believes that this discovery could help the Brassicales increase their defense. Their genes could be altered in such a way that the crops will be pest-resistant.
Image Source: The Guardian