Table 2: Stable isotope data from Cretaceous eggshells and associated phases.

From: Isotopic ordering in eggshells reflects body temperatures and suggests differing thermophysiology in two Cretaceous dinosaurs

Species or material*Localityn specimensn analysesδ13CCO3‰, V-PDBδ18OCO3‰, V-PDBΔ47‰, ARF§Δ47 Temp. (°C) inorganic eq.||Δ47 Temp. (°C) biogenic eq.δ18Owater ‰, V-SMOW#
Apparently well-preserved eggshells:
 OviraptoridUkhaa Tolgod39−5.7±0.3−2.1±0.20.671±0.01230.3±2.631.9±2.91.6±0.2
 TitanosauridAuca Mahuevo, level 437−12.7±0.00.4±0.00.650±0.00635.3±1.437.6±1.95.2±0.2
Eggshells of uncertain preservation:
 Putative titanosauridRousset, layers B–D67−9.2±0.3−4.8±0.10.642±0.00537.0±1.239.6±1.40.4±0.3
 OviraptoridBugin Tsav37−5.5±0.3−9.7±1.30.674±0.00529.7±1.031.3±1.2−6.4±0.5
 OviraptoridBayn Dzak12−3.6±0.0−11.5±0.10.684±0.01427.5±2.928.8±3.3−8.4±1.3
 Morphotype 2Ukhaa Tolgod413−5.7±0.2−3.0±0.40.667±0.00331.2±0.832.9±0.81.0±0.3
Poorly preserved eggshells:
 OviraptoridUkhaa Tolgod28−6.6±0.3−8.1±0.20.681±0.00928.2±1.929.6±2.2−4.8±0.8
 TitanosauridAuca Mahuevo, level 248−12.6±0.1−0.2±0.10.624±0.00441.6±0.944.8±1.06.0±0.1
 Putative titanosauridRoques Hautes36−10.5±0.4−3.4±0.70.616±0.01343.6±3.347.0±3.83.2±1.1
 Putative titanosauridRousset, layer A36−13.2±0.21.2±0.60.633±0.00139.4±0.442.3±0.46.9±0.6
Associated phases:
 Nodular carbonatesUkhaa Tolgod99−3.3±0.2−11.0±0.30.694±0.01125.2±2.326.3±2.6−7.9±0.3
 Spar calciteUkhaa Tolgod11−6.4±0.0−12.2±0.00.689±0.00726.4±1.427.6±1.6−8.9±0.4
 BoneUkhaa Tolgod11−3.6±0.0−11.7±0.00.668±0.01031.0±2.132.8±2.4−7.5±0.6
 Nodular carbonatesRoques Hautes77−8.9±0.1−4.9±0.10.641±0.00637.4±1.540.0±1.70.0±0.2
 Bulk sedimentAuca Mahuevo, level 211−9.8±0.0−4.6±0.00.630±0.00740.0±1.843.0±2.01.2±0.5
  1. ± Values are one s.e., or in the case of water isotope values, the propagated s.e.
  2. *Samples were considered to be of uncertain preservation if not enough information from multiple sources was available to make an informed assessment or if different types of analyses were not conclusive. See Supplementary Note 3 for full description of steps taken to assess preservation, and Supplementary Table 4 for justification for classification of individual specimens.
  3. Represents the number of distinct extractions of CO2 from a sample that were separately purified and analysed. See Supplementary Table 3 for additional data for samples.
  4. Stable isotope values of the carbonate mineral.
  5. §Values given on the ‘absolute reference frame’20.
  6. ||Calculated using the inorganic calibration of Ghosh et al.19 (Equation (2); Supplementary Note 2).
  7. Calculated using a compilation of published biogenic calibration (Equation (3), Supplementary Note 2) data collected in the Caltech laboratories and synthesized by Eagle et al.26. See Supplementary Note 2 text for more information on how this calibration was derived.
  8. #δ18O of mineral formation waters calculated using the equation of Kim and O’Neil38, and using the Δ47 (Biogenic) temperature). All eggshells are calcite. Error represents propagated one s.e.