Cargando…
Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
Solenopora jurassica is a fossil calcareous alga that functioned as an important reef-building organism during the Palaeozoic. It is of significant palaeobiological interest due to its distinctive but poorly understood pink and white banding. Though widely accepted as an alga there is still debate o...
Autores principales: | , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2015
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4569467/ https://www.ncbi.nlm.nih.gov/pubmed/26367117 http://dx.doi.org/10.1371/journal.pone.0138305 |
_version_ | 1782390050406793216 |
---|---|
author | Barden, Holly E. Behnsen, Julia Bergmann, Uwe Leng, Melanie J. Manning, Phillip L. Withers, Philip J. Wogelius, Roy A. van Dongen, Bart E. |
author_facet | Barden, Holly E. Behnsen, Julia Bergmann, Uwe Leng, Melanie J. Manning, Phillip L. Withers, Philip J. Wogelius, Roy A. van Dongen, Bart E. |
author_sort | Barden, Holly E. |
collection | PubMed |
description | Solenopora jurassica is a fossil calcareous alga that functioned as an important reef-building organism during the Palaeozoic. It is of significant palaeobiological interest due to its distinctive but poorly understood pink and white banding. Though widely accepted as an alga there is still debate over its taxonomic affinity, with recent work arguing that it should be reclassified as a chaetetid sponge. The banding is thought to be seasonal, but there is no conclusive evidence for this. Other recent work has, however demonstrated the presence of a unique organic boron-containing pink/red pigment in the pink bands of S. jurassica. We present new geochemical evidence concerning the seasonality and pigmentation of S. jurassica. Seasonal growth cycles are demonstrated by X-ray radiography, which shows differences in calcite density, and by varying δ(13)C composition of the bands. Temperature variation in the bands is difficult to constrain accurately due to conflicting patterns arising from Mg/Ca molar ratios and δ(18)O data. Fluctuating chlorine levels indicate increased salinity in the white bands, when combined with the isotope data this suggests more suggestive of marine conditions during formation of the white band and a greater freshwater component (lower chlorinity) during pink band precipitation (δ(18)O). Increased photosynthesis is inferred within the pink bands in comparison to the white, based on δ(13)C. Pyrolysis Gas Chromatography Mass Spectrometry (Py-GCMS) and Fourier Transform Infrared Spectroscopy (FTIR) show the presence of tetramethyl pyrrole, protein moieties and carboxylic acid groups, suggestive of the presence of the red algal pigment phycoerythrin. This is consistent with the pink colour of S. jurassica. As phycoerythrin is only known to occur in algae and cyanobacteria, and no biomarker evidence of bacteria or sponges was detected we conclude S. jurassica is most likely an alga. Pigment analysis may be a reliable classification method for fossil algae. |
format | Online Article Text |
id | pubmed-4569467 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-45694672015-09-18 Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica Barden, Holly E. Behnsen, Julia Bergmann, Uwe Leng, Melanie J. Manning, Phillip L. Withers, Philip J. Wogelius, Roy A. van Dongen, Bart E. PLoS One Research Article Solenopora jurassica is a fossil calcareous alga that functioned as an important reef-building organism during the Palaeozoic. It is of significant palaeobiological interest due to its distinctive but poorly understood pink and white banding. Though widely accepted as an alga there is still debate over its taxonomic affinity, with recent work arguing that it should be reclassified as a chaetetid sponge. The banding is thought to be seasonal, but there is no conclusive evidence for this. Other recent work has, however demonstrated the presence of a unique organic boron-containing pink/red pigment in the pink bands of S. jurassica. We present new geochemical evidence concerning the seasonality and pigmentation of S. jurassica. Seasonal growth cycles are demonstrated by X-ray radiography, which shows differences in calcite density, and by varying δ(13)C composition of the bands. Temperature variation in the bands is difficult to constrain accurately due to conflicting patterns arising from Mg/Ca molar ratios and δ(18)O data. Fluctuating chlorine levels indicate increased salinity in the white bands, when combined with the isotope data this suggests more suggestive of marine conditions during formation of the white band and a greater freshwater component (lower chlorinity) during pink band precipitation (δ(18)O). Increased photosynthesis is inferred within the pink bands in comparison to the white, based on δ(13)C. Pyrolysis Gas Chromatography Mass Spectrometry (Py-GCMS) and Fourier Transform Infrared Spectroscopy (FTIR) show the presence of tetramethyl pyrrole, protein moieties and carboxylic acid groups, suggestive of the presence of the red algal pigment phycoerythrin. This is consistent with the pink colour of S. jurassica. As phycoerythrin is only known to occur in algae and cyanobacteria, and no biomarker evidence of bacteria or sponges was detected we conclude S. jurassica is most likely an alga. Pigment analysis may be a reliable classification method for fossil algae. Public Library of Science 2015-09-14 /pmc/articles/PMC4569467/ /pubmed/26367117 http://dx.doi.org/10.1371/journal.pone.0138305 Text en https://creativecommons.org/publicdomain/zero/1.0/ This is an open-access article distributed under the terms of the Creative Commons Public Domain declaration, which stipulates that, once placed in the public domain, this work may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. |
spellingShingle | Research Article Barden, Holly E. Behnsen, Julia Bergmann, Uwe Leng, Melanie J. Manning, Phillip L. Withers, Philip J. Wogelius, Roy A. van Dongen, Bart E. Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica |
title | Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
|
title_full | Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
|
title_fullStr | Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
|
title_full_unstemmed | Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
|
title_short | Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
|
title_sort | geochemical evidence of the seasonality, affinity and pigmenation of solenopora jurassica |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4569467/ https://www.ncbi.nlm.nih.gov/pubmed/26367117 http://dx.doi.org/10.1371/journal.pone.0138305 |
work_keys_str_mv | AT bardenhollye geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica AT behnsenjulia geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica AT bergmannuwe geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica AT lengmelaniej geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica AT manningphillipl geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica AT withersphilipj geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica AT wogeliusroya geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica AT vandongenbarte geochemicalevidenceoftheseasonalityaffinityandpigmenationofsolenoporajurassica |