A unique coral biomineralization pattern has resisted 40 million years of major ocean chemistry change.
Today coral reefs are threatened by changes to seawater conditions associated with rapid anthropogenic global climate change. Yet, since the Cenozoic, these organisms have experienced major fluctuations in atmospheric CO2 levels (from greenhouse conditions of high pCO2 in the Eocene to low pCO2 ice-house conditions in the Oligocene-Miocene) and a dramatically changing ocean Mg/Ca ratio. Here we show that the most diverse, widespread, and abundant reef-building coral genus Acropora (20 morphological groups and 150 living species) has not only survived these environmental changes, but has maintained its distinct skeletal biomineralization pattern for at least 40 My: Well-preserved fossil Acropora skeletons from the Eocene, Oligocene, and Miocene show ultra-structures indistinguishable from those of extant representatives of the genus and their aragonitic skeleton Mg/Ca ratios trace the inferred ocean Mg/Ca ratio precisely since the Eocene. Therefore, among marine biogenic carbonate fossils, well-preserved acroporid skeletons represent material with very high potential for reconstruction of ancient ocean chemistry.
Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, PL-00-818 Warsaw, Poland.
Jarosław
J
Stolarski
Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy.
Francesca R
FR
Bosellini
Biodiversity &Geosciences Program, Queensland Museum, South Brisbane, Qld 4101, Australia.
Carden C
CC
Wallace
University of Washington, School of Oceanography, Box 357940, WA 98195-7940, Seattle, USA.
Anne M
AM
Gothmann
Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
Maciej
M
Mazur
MCAM UMR7245 Muséum National d'Histoire Naturelle - CNRS, Sorbonne-Universités, Paris, France.
Isabelle
I
Domart-Coulon
The Mina &Everard Goodman Faculty of Life Science, Bar-Ilan University, 52900 Ramat-Gan, Israel.
Eldad
E
Gutner-Hoch
Institut für Geologie, Mineralogie und Geophysik, Ruhr-Universität Bochum, D-44780 Bochum, Germany.
Rolf D
RD
Neuser
The Mina &Everard Goodman Faculty of Life Science, Bar-Ilan University, 52900 Ramat-Gan, Israel.
Oren
O
Levy
Department of Earth and Planetary Sciences, The Weizmann Institute of Science, P.O. Box 26, 76100 Rehovot, Israel.
Aldo
A
Shemesh
Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.|Center for Advanced Surface Analysis, Institute of Earth Sciences, Université de Lausanne, CH-1015 Lausanne, Switzerland.
Anders
A
Meibom
D000818:Animals; D037421:Anthozoa / Q000737:chemistry* / Q000145:classification / Q000502:physiology / Q000648:ultrastructure; D002113:Calcification, Physiologic; D002118:Calcium / Q000737:chemistry; D002245:Carbon Dioxide / Q000737:chemistry*; D057894:Coral Reefs; D005580:Fossils / Q000266:history* / Q000648:ultrastructure; D049690:History, Ancient; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry; D009792:Oceans and Seas; D010802:Phylogeny; D012623:Seawater / Q000737:chemistry*; D013696:Temperature
D002245:Carbon Dioxide; D008274:Magnesium; D002118:Calcium