Cooler winters as a possible cause of mass extinctions at the Eocene/Oligocene boundary

  title={Cooler winters as a possible cause of mass extinctions at the Eocene/Oligocene boundary},
  author={Linda C. Ivany and William P. Patterson and Kyger C. Lohmann},
The Eocene/Oligocene boundary, at about 33.7 Myr ago, marks one of the largest extinctions of marine invertebrates in the Cenozoic period. For example, turnover of mollusc species in the US Gulf coastal plain was over 90% at this time. A temperature change across this boundary—from warm Eocene climates to cooler conditions in the Oligocene—has been suggested as a cause of this extinction event, but climate reconstructions have not provided support for this hypothesis. Here we report stable… 
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Synchronous turnover of flora, fauna, and climate at the Eocene–Oligocene Boundary in Asia
The results show that climate change forced a turnover of flora and fauna, suggesting there was a change from large-size perissodactyl-dominant fauna in forests under a warm-temperate climate to small rodent/lagomorph-Dominantfauna in forest-steppe in a dry- Temperate climate across the Eocene–Oligocene Boundary.
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Onset of long-term cooling of Greenland near the Eocene-Oligocene boundary as revealed by branched tetraether lipids
The Eocene-Oligocene (E-O) boundary interval is considered to be one of the major transitions in Earth’s climate, witnessing the fi rst major expansion of the East Antarctic Ice Sheet. However, the
Shallow-marine ostracode turnover during the Eocene–Oligocene transition in Mississippi, the Gulf Coast Plain, USA
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Oxygen isotope data from planktonic foraminifera for the warm Eocene epoch suggest that tropical sea-surface temperatures (SSTs) may have been cooler than at present. Such data have stimulated
Terrestrial cooling in Northern Europe during the Eocene–Oligocene transition
The authors' data show a decrease in growing-season surface water temperatures corresponding to an average decrease in mean annual air temperature from the Late Eocene to Early Oligocene, which suggests a close linkage between atmospheric carbon dioxide concentrations, Northern Hemisphere temperature, and expansion of the Antarctic ice sheets.
Eocene–Oligocene latitudinal climate gradients in North America inferred from stable isotope ratios in perissodactyl tooth enamel
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Migration of a Late Cretaceous fish
The ontogenetic history of a Maastrichtian-age fish, Vorhisia vulpes, is reconstructed by using the carbon, oxygen and strontium isotope ratios of four aragonite otoliths collected from the Fox Hills Formation of South Dakota.


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The Eocene-Oligocene boundary is widely cited as the "other" example (besides the Cretaceous-Tertiary boundary) of a known relationship between mass extinctions and bolide impacts. The stratigraphic
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The equator to high southern latitude sea surface and vertical temperature gradients are reconstructed from oxygen isotope values of planktonic and benthic foraminifers for the following five time
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Abstract Biostratigraphic zonation of the Paleogene formations in the eastern Gulf Coastal Plain of the U.S.A., based on calcareous nannoplankton, allows a reassessment of the timing and pattern of
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Molluscs removed from 12 bulk samples of the Yazoo Formation (upper Eocene), exposed in a quarry at Cynthia, Mississippi, are similar in composition and diversity to those found in the underlying
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Eocene to Oligocene marine carbonate shelf deposits in a continuous core in Baldwin County, Alabama, were evaluated within a sequence stratigraphic framework to determine characteristic stable