TY - JOUR

T1 - Effect of a Jurassic oceanic anoxic event on belemnite ecology and evolution

AU - Ullmann, Clemens Vinzenz

AU - Thibault, Nicolas Rudolph

AU - Ruhl, Micha

AU - Hesselbo, Stephen P

AU - Korte, Christoph

PY - 2014/7/15

Y1 - 2014/7/15

N2 - The Toarcian oceanic anoxic event (T-OAE; ∼183 million y ago) ispossibly the most extreme episode of widespread ocean oxygendeficiency in the Phanerozoic, coinciding with rapid atmosphericpCO2 increase and significant loss of biodiversity in marine faunas.The event is a unique past tipping point in the Earth system, whererapid and massive release of isotopically light carbon led to a majorperturbation in the global carbon cycle as recorded in organic andinorganic C isotope records. Modern marine ecosystems are projectedto experience major loss in biodiversity in response toenhanced ocean anoxia driven by anthropogenic release of greenhousegases. Potential consequences of this anthropogenic forcingcan be approximated by studying analog environmental perturbationsin the past such as the T-OAE. Here we present to our knowledgethe first organic carbon isotope record derived from theorganic matrix in the calcite rostra of early Toarcian belemnites.We combine both organic and calcite carbon isotope analyses ofindividual specimens of these marine predators to obtain a refinedreconstruction of the early Toarcian global exogenic carbon cycleperturbation and belemnite paleoecology. The organic carbon isotopedata combined with measurements of oxygen isotope valuesfrom the same specimens allow for a more robust interpretation ofthe interplay between the global carbon cycle perturbation, environmentalchange, and biotic response during the T-OAE. We inferthat belemnites adapted to environmental change by shifting theirhabitat from cold bottom waters to warm surface waters in responseto expanded seafloor anoxia.

AB - The Toarcian oceanic anoxic event (T-OAE; ∼183 million y ago) ispossibly the most extreme episode of widespread ocean oxygendeficiency in the Phanerozoic, coinciding with rapid atmosphericpCO2 increase and significant loss of biodiversity in marine faunas.The event is a unique past tipping point in the Earth system, whererapid and massive release of isotopically light carbon led to a majorperturbation in the global carbon cycle as recorded in organic andinorganic C isotope records. Modern marine ecosystems are projectedto experience major loss in biodiversity in response toenhanced ocean anoxia driven by anthropogenic release of greenhousegases. Potential consequences of this anthropogenic forcingcan be approximated by studying analog environmental perturbationsin the past such as the T-OAE. Here we present to our knowledgethe first organic carbon isotope record derived from theorganic matrix in the calcite rostra of early Toarcian belemnites.We combine both organic and calcite carbon isotope analyses ofindividual specimens of these marine predators to obtain a refinedreconstruction of the early Toarcian global exogenic carbon cycleperturbation and belemnite paleoecology. The organic carbon isotopedata combined with measurements of oxygen isotope valuesfrom the same specimens allow for a more robust interpretation ofthe interplay between the global carbon cycle perturbation, environmentalchange, and biotic response during the T-OAE. We inferthat belemnites adapted to environmental change by shifting theirhabitat from cold bottom waters to warm surface waters in responseto expanded seafloor anoxia.

KW - Faculty of Science

KW - Ecology

KW - Belemnites

KW - Oceanic Anoxic Event

KW - Toarcian

KW - Carbon Isotopes

KW - Oxygen isotopes

U2 - 10.1073/pnas.1320156111

DO - 10.1073/pnas.1320156111

M3 - Journal article

C2 - 24982187

VL - 111

SP - 10073

EP - 10076

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 28

ER -