Some mosses thrive on a tiny fraction of the sunlight others require

Evidence

Schistostega pennata, the Goblins’ Gold, is unlike any other moss. It is a paragon of minimalism, simple in means, rich in ends. So simple you might not recognize it as a moss at all. The more typical mosses on the bank outside spread themselves out to meet the sun. Such robust leaves and shoots, though tiny, require a substantial amount of solar energy to build and maintain. They are costly in the solar currency. Some mosses need full sun to survive, others favor the diffuse light of clouds, while Schistostega lives on the clouds’ silver lining alone. Inside the shoreline caves light is reduced to mere watery reflections from the lake surface. … It is only one-tenth of one percent of the light outside. — Robin Wall Kimmerer, Gathering Moss, 628

Categorization

• XREF: Connects to the eco-justice thread of organisms thriving at margins and to the observational lesson that scarcity of one resource (light) forces architecture minimalism, echoing ch12’s point on leaves optimizing for water where trees optimize for light. — connects to: Moss leaf shape optimizes for water where trees optimize for light — Robin Wall Kimmerer, Gathering Moss: A Natural and Cultural…, 191; Cellular lenslike facets let Schistostega focus scarce light onto one chloroplast — Robin Wall Kimmerer, Gathering Moss: A Natural and Cultural…, 632; Light scarcity forces Schistostega to abandon leaves and shoots entirely — Robin Wall Kimmerer, Gathering Moss: A Natural and Cultural…, 630