Isotopologue thermometry of fossil hard tissues: A new approach to inferring dinosaur body temperature.

恐龙是冷血动物还是温血动物？越来越多的生理模型、解剖特征、骨骼显微结构和氧同位素数据表明，至少有一些恐龙是恒温的，甚至是吸热的。为了更好地了解恐龙，特别是巨型蜥脚类恐龙的热生理，将使用基于碳酸盐矿物的13 C-18 O过量温度关系的新型化学同位素温度计来确定恐龙体温。该方法将通过分析具有已知体温的现存脊椎动物的骨骼和釉质来校准含碳酸盐的骨骼生物磷灰石。保存化石硬组织中的原始同位素组成是用这种化学温度计测定已灭绝脊椎动物体温的关键。这将通过不同的矿物学和地球化学方法进行测试。将分析保存完好的恐龙蛋壳和牙釉质磷灰石中的13 C-18 O过量碳酸盐，以确定这些生物硬组织的生物矿化温度，从而确定恐龙体温。牙齿和蛋壳的各种蜥脚类动物类群不同的身体大小，个体发育年龄，并从一系列的paleolatitudes，以及牙齿同域变温脊椎动物将进行分析，以确定他们的体温。埋藏温度将推断从成岩碳酸盐包埋沉积物或同一牙齿标本的蚀变牙本质。

Were dinosaurs cold-blooded or warm-blooded animals? There is growing evidence from physiological models, anatomical features, bone microstructure, and oxygen isotope data indicating that at least some dinosaurs were homeothermic or even endothermic. For a better understanding of the thermophysiology of dinosaurs and the gigantic sauropods in particular, dinosaur body temperatures will be determined using a novel chemical isotopologue thermometer based on the 13C-18Oexcess-temperature relation for carbonate minerals. This method will be calibrated for carbonate containing skeletal bioapatite by analyzing bones and enamel of extant vertebrates with known body temperatures. Preservation of the original isotope composition in fossil hard tissues is crucial for determining body temperatures of extinct vertebrates with this chemical thermometer. This will be tested by different mineralogical and geochemical methods. The 13C-18Oexcess of carbonate in well preserved dinosaur eggshells and tooth enamel apatite will be analyzed to determine the biomineralisation temperature of these biogenic hard tissues and hence the dinosaur body temperature. Teeth and eggshells of various sauropod taxa of different body size, ontogenetic age, and from a range of paleolatitudes, as well as teeth from sympatric ectothermic vertebrates will be analyzed to determine their body temperatures. Burial temperatures will be inferred from diagenetic carbonates of the embedding sediment or the altered dentine of the same tooth specimens.