themarginalian.org · 6 hours ago

Why Leaves Change Color and How We Become Who We Are: the Science of Chlorophyll and the Poetics of Personhood...

Maria Popova traces the science of autumn leaf color back through two centuries of discovery, finding in chlorophyll's seasonal retreat something far larger than botany. When daylight fades and trees stop producing chlorophyll, the other pigments that were present all along - the yellows, oranges, and reds - are finally free to show themselves, which Popova reads as "a living reminder that every loss reveals what we are made of." Even more startling: under ultraviolet light, ripening bananas produce a blue fluorescent pigment invisible to the human eye, a discovery that arrived two hundred years after chlorophyll was first named and identified. The scientists who named it in 1817 offered a quiet model of intellectual humility, writing that they had "no right to name a substance long-known" and proposing their term only tentatively, "without granting it any importance." In that restraint, and in the ongoing mystery of a molecule nature invented more than a billion years ago, Popova finds an honest portrait of the human condition: creatures straining toward understanding with limited senses, forever reaching, as Maria Mitchell once wrote, only "a bit of the curtain that hides the infinite from us" - and finding that thrilling rather than defeating.