Cretaceous Jehol Biota Lived in a Cold Climate

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

Authors:

1. Romain Amiot (a,1,2)

2. Xu Wang (b),

3. Zhonghe Zhou (a)

4. Xiaolin Wang (a)

5. Eric Buffetaut(c)

6. Christophe Lécuyer(d,2)

7. Zhongli Ding(b)

8. Frédéric Fluteau(e)

9. Tsuyoshi Hibino(f)

10. Nao Kusuhashi(g)

11. Jinyou Mo(h)

12. Varavudh Suteethorn(i)

13. Yuanqing Wang(a)

14. Xing Xu (a)

15. Fusong Zhang(b)

Institutions:

a) Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), 142 Xi Zhi Men Wai DaJie, Beijing 100044, China;

b) Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, 19 Beitucheng Xilu, Beijing 100029, China;

c) CNRS (Centre National de la Recherche Scientifique) UMR (Unité Mixte de Recherche) 8538, Laboratoire de Géologie de l’Ecole Normale Supérieure, 24, Rue Lhomond, 75231 Paris Cedex 05, France;

d) CNRS (Centre National de la Recherche Scientifique) UMR (Unité Mixte de Recherche) 5125, Université Claude Bernard Lyon 1, 2, Rue Raphaël Dubois, 69622 Villeurbanne Cedex, France;

e) Institut de Physique du Globe de Paris, 1 Rue Jussieu, 75238 Paris Cedex 05, France;

f) Shiramine Institute of Paleontology, Kuwajima, Hakusan, Ishikawa 920-2502, Japan;

g) Department of Earth's Evolution and Environment, Graduate School of Science and Engineering, Ehime University, 2-5 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan;

h) Faculty of Earth Sciences, China University of Geosciences, 388 Lumo Road, Wuhan 430074, China;

i)Department of Mineral Resources, Rama VI Road, Bangkok 10400, Thailand

Abstract:

Early Cretaceous vertebrate assemblages from East Asia and parti- cularly the Jehol Biota of northeastern China flourished during a period of highly debated climatic history. While the unique charac- ters 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 phos- phate (δ18 Op ) from various reptile remains recovered from China, Thailand, and Japan. δ18Op values indicate that cold terrestrial cli- mates 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 agree- ment 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 north- eastern 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.

Interesting. And it makes sense. This is not the first time that there has been a deviation from the hot house model for the Cretaceous. I'm reading the paper slowly because I have a lot to do. However, take a look. Link in the title, as always.