The biogenicity of modern terrestrial roll-up structures and its significance for ancient life on land

H. Beraldi-Campesi, Ferran Garcia-Pichel

Research output: Contribution to journalArticlepeer-review

26 Scopus citations


Roll-up structures (Roll-ups) are sedimentary structures formed by the desiccation-mediated curling of a surface, cohesive layer into a subcylindrical, coiled shape. Their origin in terrestrial environments has been attributed to the shrinking effect of argillaceous components, while microbes are thought to be the curling agent in intertidal marine settings. Roll-ups also exist in terrestrial environments and the rock record, but their genesis is unclear. Proving a biogenic origin of terrestrial roll-ups would make them excellent biosignatures to track ancient life on land. In this study, we tested the biogenicity of modern roll-ups from arid terrestrial environments, showing that, regardless of their geographic location and textural properties, they invariably contained large and distinct cyanobacterial populations compared to adjacent, non-rolled surface soil. Cyanobacterial populations inhabiting these roll-ups were genetically diverse, but consistently dominated by filamentous, non-heterocystous forms. We could also recreate roll-ups artificially by desiccating clay and organic polysaccharide slurries on sandy substrates, and show that clay roll-ups were less prone to re-form after wetting-and-drying cycles and less resistant to erosion than organically bound or naturally occurring ones. All this evidence suggests that fossil roll-ups found in ancient terrestrial deposits are biogenic features.

Original languageEnglish (US)
Pages (from-to)10-23
Number of pages14
Issue number1
StatePublished - Jan 2011

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Environmental Science(all)
  • Earth and Planetary Sciences(all)


Dive into the research topics of 'The biogenicity of modern terrestrial roll-up structures and its significance for ancient life on land'. Together they form a unique fingerprint.

Cite this