Carbonate “clumped” isotope signatures in aragonitic scleractinian and calcitic gorgonian deep-sea corals

Aragonitic scleractinian corals in the Cretaceous calcitic sea

Changes in seawater chemistry have affected the evolution of calcifying marine organisms, including their skeletal polymorph (calcite versus aragonite), which is believed to have been strongly influenced by the Mg/Ca ratio at the time these animals first emerged. However, we show that micrabaciids, a scleractinian coral clade that first appeared in the fossil record of the Cretaceous, when the ...

Carbonate clumped isotope thermometry of deep-sea corals and implications for vital effects

Here we calibrate the carbonate clumped isotope thermometer in modern deep-sea corals. We examined 11 specimens of three species of deep-sea corals and one species of a surface coral spanning a total range in growth temperature of 2–25 C. External standard errors for individual measurements ranged from 0.005& to 0.011& (average: 0.0074&) which corresponds to 1–2 C. External standard errors for ...

Statistical clumped isotope signatures

High precision measurements of molecules containing more than one heavy isotope may provide novel constraints on element cycles in nature. These so-called clumped isotope signatures are reported relative to the random (stochastic) distribution of heavy isotopes over all available isotopocules of a molecule, which is the conventional reference. When multiple indistinguishable atoms of the same e...

Estimating Cambro-Ordovician seawater temperature and isotopic composition using carbonate clumped isotope paleothermometry on calcitic and phosphatic fossils

Iodine in Gorgonian Corals

In 1896 Drechsel demonstrated that the horny axial skeleton of the Mediterranean coral, Gorgonia cuvolinii, contains iodine in organic combination in a nitrogenous substance termed gorgonin by him. Hundeshagen (1895) had previously investigated an iodine-containing organic material which he separated from marine sponges; and later Harnack (1898) isolated from the same source a compound which he...