Determining Whether Differences in Morphology Across an Elevation Gradient is the Result of Long Term Environmental Plasticity or Genetic Population Differentiation in Keystone Biocrust Moss: Syntrichia caninervis
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Unlike vascular plants, mosses are at higher risk for water scarcity in deserts because they experience higher temperatures and intense solar radiation which are known to limit growth and abundance, and because they lack specialized tissues and structures to transport water internally from below ground. Prior research done in the Mojave Desert on a keystone soil moss species, Syntrichia caninervis, observed differences in morphology related to plant size across three life zones (vegetation communities) influenced by elevation (low-890m, medium-1680m, high-2060m) and a water-stress gradient. Our study used a laboratory common garden by culturing 22 S. caninervis genotypes compiled from each life zone and measuring the resulting adult morphology to determine if phenotypic variation was due to genetic differences in a given population or environmental plasticity. Common garden morphometrics were compared to source field genotypes and included length of shoots, leaves, and leaf points (awns), and leaf length and width. We found that mean field shoot height, awn and leaf length, and leaf width trended upwards with elevation. In garden shoots, we found evidence for genotypic effects as this pattern was largely retained except for shoot height, which is thus a stress-induced trait. Three genotypes lacking field awns developed awns in culture, evidencing plasticity. This research advances moss ecology by confirming phenotypic plasticity for shoot height and awns over an elevation gradient. Second and third generation cultures will be grown in the future to confirm whether the observed life zone trait patterns are genetic or due to long-term plasticity.
Plasticity; Common garden; Mophometrics; Mojave Desert
Davis, Andie, "Determining Whether Differences in Morphology Across an Elevation Gradient is the Result of Long Term Environmental Plasticity or Genetic Population Differentiation in Keystone Biocrust Moss: Syntrichia caninervis" (2021). Undergraduate Research Symposium Podium Presentations. 7.