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Biological soil crusts (BSCs) are ubiquitous and crucial components of modern dryland ecosystems and probably were the first community type to colonize the Precambrian land surface. BSCs are complex symbioses of eubacteria, cyanobacteria, green algae, mosses, lichens, and fungi. BSCs, having adapted to intense ultraviolet radiation and drastic variations in precipitation and temperature, have likely been prevalent in terrestrial environments since the Precambrian and are undoubtedly under-reported in the rock record. This is probably due to the crusts' inconspicuous appearance and preservational taphonomy. In order to improve understanding of the diverse appearances of BSCs in sedimentary strata, this study reviews the biology, biologically produced structures, and morphological variation of modem BSCs using examples from Colorado Plateau BSC of southern Utah (Grand Staircase-Escalante National Monument). Sediment coring into modern BSCs identified a variety of pedouenic features. Simple compaction experiments on the cores illustrate the taphonomic destruction of pedouenic features. In addition, a comparison of the modern BSC features to those preserved in a Cretaceous BSC found in Utah demonstrates the utility of understanding the nature of the various stages of development of modern BSCs. These descriptions of potentially preserved expressions of BSCs should facilitate identification and separation of fossilized BSCs from other physical sedimentary structures.