The secret lives of desert moss

Abstract

Desert plants experience extreme fluctuations in light, temperature, and water availability. These intense conditions shape the development, life history, and evolutionary trajectory of desert mosses. In this talk, I will present on two such processes: vegetative growth and sexual reproduction. First, I discuss the discovery of Mojave Desert mosses occurring as hypoliths under milky quartz rocks. To characterize this unique moss microhabitat, we deployed microclimate dataloggers and collected samples in a Mojave site containing quartz hypoliths. The results of this study highlight the need to consider microhabitats, especially in extreme environments where mosses may find refuge from the prevailing macroclimatic conditions. Second, I discuss how natural populations of many desert mosses appear highly female-biased based on the presence of reproductive structures. The dryland moss Syntrichia caninervis is notable for its low frequency of sex expression and strong female bias. Using molecular methods, we uncovered the genetic sex of non-expressing shoots and compare the patterns of phenotypic and genotypic sex ratios in Mojave populations. The findings shared in this talk contribute to our understanding of how the environment may modulate habitat filtering, vegetative growth, and sexual reproduction in S. caninervis either through its direct influence on physiology or through selection.

Jenna Ekwealor

Biodiversity Genomics Postdoctoral Researcher

I am a Biodiversity Genomics Postdoctoral Fellow studying evolutionary eco-physiology of stress tolerance in plants with the Smithsonian Institution Data Science Lab.