In recent years, problems related to global environmental disturbances have been growing more and more. In ancient times, inoceramid bivalves managed to survive by changing their species diversity and size over one meter to one centimeter, and by replacing themselves with newly originated species in order to adapt to global environmental changes, but finally they had been extinct in the Cretaceous. However, this fact is not commonly known, although it is well-known that dinosaurs had been ruined due to ancient global environmental disturbances by an extraterrestrial impact. The author took an interest in the extremely sensitive responses of inoceramid bivalves to a variety of global environment changes, examined extensively the specimens of fossils collected in Hokkaido, Japan and made a comprehensive survey of relevant literature. The author would like to provide paleontologists, geologists, earth scientists and experts of environmental protection, as well as students and people being interested in the relevant field with those findings and information. The author is also very happy if this monograph gives some kinds of hint for protection against global environmental destruction.

Akinori TAKAHASHI, Ph.D.Visiting Researcher, Research Institute for Science andEngineering, Waseda UniversityPart-time Lecturer, Faculty of Education and Integrated Arts andSciences, Waseda University