Jeanne reveals which branches of the evolutionary tree of plants bear edible leaves and speculates about why that is.

Giant coconut palm (Cocos nucifera) fronds dwarf me

Most of the 300,000 + plant species have leaves, and the function of all of them is to perform photosynthesis.  They are the ultimate source for all of the oxygen and food for the rest of the food chain and help regulate the global carbon and water cycles.  They are also nutrition superstars.  To figure out why greens are good for you and whether all leaves are equal in this regard, we need to take quick look at global leaf structural variability and broad evolutionary patterns in the species that make their way onto our tables. Continue reading →