Implications of a 3.472–3.333 Gyr-old subaerial microbial mat from the Barberton greenstone belt, South Africa for the UV environmental conditions on the early Earth
Pourquoi ce travail est-il dans la base ?
Une base qui oublie comment elle a trouvé un travail ne peut pas être vérifiée. Voici les voies qui ont admis celui-ci.
Dossier post-publication
- Nature
- Correction
- Motif
- Concerns/Issues about Authorship/Affiliation;
- Date
- 12/29/2006 0:00
- Signalé par OpenAlex ?
- Oui
Source : Retraction Watch, jointe par DOI. OpenAlex consigne la rétractation dans is_retracted, un booléen sur un espace d'états à au moins quatre valeurs ; il ne peut donc exprimer ni une expression de préoccupation, ni une correction, ni un rétablissement, et les rapporte comme false, ce qui se lit comme « rien à signaler ».
Résumé
Modelling suggests that the UV radiation environment of the early Earth, with DNA weighted irradiances of about three orders of magnitude greater than those at present, was hostile to life forms at the surface, unless they lived in specific protected habitats. However, we present empirical evidence that challenges this commonly held view. We describe a well-developed microbial mat that formed on the surface of volcanic littoral sediments in an evaporitic environment in a 3.5-3.3Ga-old formation from the Barberton greenstone belt. Using a multiscale, multidisciplinary approach designed to strongly test the biogenicity of potential microbial structures, we show that the mat was constructed under flowing water by 0.25 microm filaments that produced copious quantities of extracellular polymeric substances, representing probably anoxygenic photosynthesizers. Associated with the mat is a small colony of rods-vibroids that probably represent sulphur-reducing bacteria. An embedded suite of evaporite minerals and desiccation cracks in the surface of the mat demonstrates that it was periodically exposed to the air in an evaporitic environment. We conclude that DNA-damaging UV radiation fluxes at the surface of the Earth at this period must either have been low (absorbed by CO2, H2O, a thin organic haze from photo-dissociated CH4, or SO2 from volcanic outgassing; scattered by volcanic, and periodically, meteorite dust, as well as by the upper layers of the microbial mat) and/or that the micro-organisms exhibited efficient gene repair/survival strategies.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
La notice
- Revue
- Philosophical Transactions of the Royal Society B Biological Sciences
- Thématique
- Planetary Science and Exploration
- Domaine
- Physics and Astronomy
- Établissements canadiens
- Western University
- Organismes subventionnaires
- —
- Mots-clés
- SubaerialGreenstone beltAstrobiologyEarly EarthMicrobial matVolcanoEvaporiteBanded iron formationGeologyGeochemistryMars Exploration ProgramEarth sciencePrecambrianCyanobacteriaArcheanBiologyPaleontologyBacteriaSedimentary rock
- Résumé présent dans OpenAlex
- oui