中国科学院古脊椎动物与古人类研究所法籍博士后Romain Amiot与中科院地质与地球物理研究所王旭等组成的一个多国合作团队近日在著名学术刊物美国《国家科学院院刊》（PNAS）发表了一篇题为“东亚地区恐龙氧同位素揭示早白垩世寒冷的气候”(Oxygen isotopes of East Asian dinosaurs reveal exceptionally cold Early Cretaceous climate) 的论文。这项他在博士后期间完成的研究表明，恐龙生活时期不全是温暖的气候，至少在早白垩世的某些阶段（如著名的热河生物群繁盛的时期，距今约1.25亿年前），中国东北地区为温带气候为主，冬天寒冷。这一结论可能还会对研究这一时期恐龙羽毛的功能提供一些启示。

他们采集的分析样品来自恐龙、似哺乳爬行动物、鳄类、龟类和鱼类化石的牙齿和骨骼，包括了中国以及日本和泰国相同时期的地层中的化石。通过对样品中氧同位素的分析，对亚洲地区早白垩世的大气温度进行了恢复。他们的研究结果显示，早白垩世这一时期的平均温度与今天相同纬度的地区气候大致相当。因此，热河生物群应当生活在一个较为寒冷的温带气候中，恐龙、鸟类和哺乳类的羽毛或者毛发能够帮助这些动物在冬天保持活力。

Amiot博士从2007开始与中科院古脊椎所周忠和研究员以及中科院地质与地球物理研究所丁仲礼院士等合作开展博士后研究，重点是对中生代脊椎动物的骨骼和牙齿进行氧、碳同位素的分析，从而恢复当时生物的习性和古气候。他于2010年出站后，在法国科学研究院（CNRS）获得了终身研究职位。

原始出处：

PNAS  doi: 10.1073/pnas.1011369108

Oxygen isotopes of East Asian dinosaurs reveal exceptionally cold Early Cretaceous climates

Romain Amiota,1,2, Xu Wangb, Zhonghe Zhoua, Xiaolin Wanga, Eric Buffetautc, Christophe Lécuyerd,2, Zhongli Dingb, Frédéric Fluteaue, Tsuyoshi Hibinof, Nao Kusuhashig, Jinyou Moh, Varavudh Suteethorni, Yuanqing Wanga, Xing Xua, and Fusong Zhangb

Abstract

Early Cretaceous vertebrate assemblages from East Asia and particularly the Jehol Biota of northeastern China flourished during a period of highly debated climatic history. While the unique characters of these continental faunas have been the subject of various speculations about their biogeographic history, little attention has been paid to their possible climatic causes. Here we address this question using the oxygen isotope composition of apatite phosphate (δ) from various reptile remains recovered from China, Thailand, and Japan. δ values indicate that cold terrestrial climates prevailed at least in this part of Asia during the Barremian—early Albian interval. Estimated mean air temperatures of about 10 ± 4 °C at midlatitudes (～42 °N) correspond to present day cool temperate climatic conditions. Such low temperatures are in agreement with previous reports of cold marine temperatures during this part of the Early Cretaceous, as well as with the widespread occurrence of the temperate fossil wood genus Xenoxylon and the absence of thermophilic reptiles such as crocodilians in northeastern China. The unique character of the Jehol Biota is thus not only the result of its evolutionary and biogeographical history but is also due to rather cold local climatic conditions linked to the paleolatitudinal position of northeastern China and global icehouse climates that prevailed during this part of the Early Cretaceous.