D7
Large-sized specimens of ammonites

Taxonomy, biostratigraphy and paleobiology of ammonites have been most actively studied field of paleonology in the University of Tokyo. There is a trend of size enlargement in the evolution of ammoniates in the Cretaceous. The largest ammonite specimen in this museum attains 70 cm and 90 kg. (Takenori Sasaki & Yasuhiro Ito)

References

Matsumoto, T. (1954a) [for 1953] The Cretaceous System in the Japanese Islands. Tokyo: The Japanese Society for the Promotion of Scientific Research.

Tanabe, K. & Shigeta, Y. (1987) Ontogenetic shell variation and streamlining of some Cretaceous ammonites. Transactions and Proceedings of the Palaeontological Society of Japan. New Series 147: 165–179.