Mosses evolved two reproductive strategies trading dispersal distance against genetic novelty

Evidence

But sturdy little Tetraphis waits expectantly, for it is designed to harness the power of a raindrop. When a gemmae cup receives a direct hit, the raindrop breaks loose the gemmae and propels them outward, leaving the nest empty. The gemmae can be splashed up to fifteen centimeters away, which isn’t bad for a plant only one centimeter tall. In a favorable location, the gemmae can regenerate an entire new plant in the span of a single summer. In comparison to spores, which are at the mercy of a fickle breeze that deposits them anywhere, a rock or a rooftop or the middle of a lake, gemmae are more likely to land in the same neighborhood as their parents. As clonal propagules, the gemmae carry a combination of genes that has already proven successful on this stump. — Robin Wall Kimmerer, Gathering Moss, 323

Categorization

• XREF: The clonal-versus-sexual tradeoff parallels ch21’s finding that stable habitats favor clonal asexual reproduction, and connects to disturbance-diversity rules already developed. — connects to: Stable habitats favor clonal asexual reproduction over sexual spore production — Robin Wall Kimmerer, Gathering Moss: A Natural and Cultural…, 317; Tetraphis switches between clonal and sexual reproduction based on colony density — Robin Wall Kimmerer, Gathering Moss: A Natural and Cultural…, 340; Diversified flexibility confers resilience in unpredictable environments across scales — Robin Wall Kimmerer, Gathering Moss: A Natural and Cultural…, 343 (+2 more)
• SHARE: A raindrop-splash dispersal mechanism for a 1 cm plant is a delightful tidbit for a bryologist or naturalist friend.