Systematics and population genomics of western Syntrichia

Mon, 01 Jan 0001 00:00:00 +0000

Western North America is home to diverse and ecologically important mosses in the genus Syntrichia, including species that dominate biological soil crusts, tolerate extreme drying, and occupy a wide range of dryland and montane habitats. This project investigates relationships among western Syntrichia lineages, with an emphasis on species complexes where morphology, geography, ecology, and evolutionary history may not tell the same story. We use field collections, herbarium material, genomic data, and comparative analyses to clarify patterns of relatedness, population structure, and trait variation. A major goal is to understand how evolutionary history and environmental variation interact to shape traits involved in stress tolerance, reproduction, and habitat use. This work also incorporates controlled growth studies to distinguish flexible environmental responses from more fixed differences among lineages or populations. This project connects moss systematics with questions about adaptation, biogeography, and the evolution of survival strategies in dry and variable environments.

Variation in biocrust photosynthesis

Mon, 01 Jan 0001 00:00:00 +0000

Desert mosses experience long periods of drying interrupted by brief windows of hydration, making photosynthesis highly dependent on when, where, and how water becomes available. This project examines how biocrust-forming mosses vary in photosynthetic traits across desert environments that differ in precipitation seasonality, temperature, and atmospheric drying demand. We are especially interested in whether seasonal shifts in photosynthetic performance reflect flexible physiological plasticity, longer-term differentiation among populations, or some combination of both. Using field collections, controlled growth experiments, pigment analyses, and chlorophyll fluorescence approaches, this work asks how desert mosses balance carbon gain with protection from excess light, heat, and drought. By comparing natural variation with responses under shared growth conditions, we aim to better understand how much of this variation is environmentally responsive and how much may reflect fixed differences among populations. This project contributes to broader efforts to predict how changing precipitation regimes and warming may affect biocrust carbon balance in dryland ecosystems.

Plasticity | MEEP Lab @ SFSU

Systematics and population genomics of western Syntrichia

Variation in biocrust photosynthesis