My researches focus on evolution of terrestrial vertebrates and their paleozoogeography on the basis of skeletal remains or fossils (turtles, lizards, crocodiles, dinosaurs, frogs, carnivoran mammals in particular). To collect those vertebrate remain, we have conducted field excavations in Japan Main Islands, Ryukyu Archipelago, Indonesia, and the Gobi desert of Mongolia every year.

I study hybridization and introgression of wild and cultivated plants using molecular markers. Especially I analyze those the distinction of which from native plants are now difficult due to their naturalizaion in pre-modern times. I also study the distinction and origin of cultivars using molecular genotying. In addition, I study the problems in denomination and nomenclature of cultivated plants as a member of the Internationl Commission for the Nomenclature of Cultivated Plants.

Infrorescence of a tree cultivated as ‘Somei-yoshino’ at the Koshikawa Botanical Gardens, University of Tokyo. I demonstrated that this individual has different genotype from true ‘Somei-yoshino’, the clonallity of the latter cultivar is verified by molecular markers.

Insects adapt to various terrestrial environments. In temperate regions, to survive cold temperatures in winter is essential for insects. Thus, many insects predict the arrival of period which is not suitable for development and reproduction, and change their physiological state. I am studying how insects regulate the life cycles in response to environmental signals, by field observations and rearing experiments.

We are studying the natural history of Japan’s turtle, ecologically, ethologically and genetically. For the sea turtle, we survey the nested turtle on beach and bycaught turtle by fisheries. Furthermore, we study the ecology and disinfection technology of red-eared slider turtle, Trachemys scriputa elegans, that was established in Japan. On the other hand, we monitor relationship between human and domestic animals, such a dolphin or seal, for the animal welfare.

It is able to be defined that Archaeological Animal remains would be a mirror of their environment and subsistence including gathering, hunting and fishing, in these days.
Every animal remains from archaeological sites is suitable to environmental archaeology in this way so it would be required to identify accurately most of all animal remains from every site. Most frequent variety of sponsored research is to identify shellfish and shell growth line analysis. Recently we analyze the oxygen stable isotope ratio and the carbon stable isotope ratio about archaeological shellfish to study palaeoenvironment.

Formation of stars like the sun and planets like the earth is one of the important themes of astronomy. We study both theory and observation of star and planet formation. I investigate the star formation triggered by effects of OB stars.
Regarding the astronomy education, I managed the certificate of the astronomy guide at Okayama University of Science and the four-dimensional digital universe theater at Faculty of Biosphere-Geosphere Science.

We have to evaluate the occurrence prediction and disaster occurrence risk of landslides from inspection data. We analyze the trend of the past of the disaster, to assess whether the “when” “where” landslide disaster occurs, we are working to hazard maps.
These results are considered useful in a safe life.

Our laboratory conducts petrological research on granites widely distributed in southwestern Japan, using fieldwork as the main means of study. In addition to granite, we also reserch to tuffs and basic igneous rocks. Informatics technics, such as GIS are used in study. In addition, granite weathering, landform formation, stone material utilization, etc. are being studied.

I study influences of meteorological and climatological conditions on human life and agriculture activities.

I am inerested in researches of local meteorology such as wind, temperature, and humidity, and biometeorology such as heat or cold stresses of human, animal, and plant.

My researches have been extended by using both a meteorological observation and numerical simulation for various regions in Japan.

How the earth and planets are formed ?
I’m trying to answer this question by observing protoplanetary disks, which is the on-going planet forming site around young stars. Current large telescopes such as Subaru telescope allow us to reaveal the detailed signature of the planet formation process in the protoplanetary disks.
In addition, I’m also involved with the new development of the astronomical instrument and methed.

(Left) Artist’s illustration of the protoplanetary disk around HD142527 star
(Right) Detection of olivine and pyroxene crystals around Hen3-600A star

I am actively involved in paleontological excavations spanning Mongolia, Kenya, and northern Okayama Prefecture, while simultaneously conducting meticulous paleoenvironmental reconstructions based on robust geological investigations. Moreover, my endeavors extend to the comprehensive reconstruction of the entire ecological framework of the relevant time periods, encompassing small vertebrates, insects, and invertebrates, achieved through the discernment of the intricate interconnections between fossils and their corresponding stratigraphic contexts. Furthermore, our team enthusiastically engages in lifelong learning endeavors, exemplified by organizing exhibitions, workshops, and lectures that showcase esteemed fossil specimens.

How can the population ｓustain in wetlands where the environment spatially and temporally fluctuates? We study the ecology of amphibians and reptiles in wetlands as target areas. Also, we study the anthropogenic impacts, such as paddy improvement and abandonment, on those populations from the viewpoint of conservation biology as well as ecology and evolution.

My research is focused on the diversification and evolution of flowering plants, mainly Cyperaceae (sedges family), ranged from Japan to the Himalayas through China. Cyperaceae is one of the most diversified group in flowering plants, and is suitable for studies of plant systematic and evolution. I have conducted taxonomic, phylogenetic and cytological studies of Cyperaceae.

Based on fieldwork in flood zones from the Himalayan highlands above 4,000 meters to the zero-meter flood zones, we are trying to elucidate the actual disaster conditions and land development processes in each region. In contrasting between regions, we emphasize primary data and attempt to relativize the issues.

Bone histology is the study of bone function and growth by sectioning bones into thin slices to visualize internal tissues. This technique has proven instrumental in uncovering the physiology and ecology of extinct animals, providing insights into their growth rate, age, metabolism, and degree of aquatic adaptation — factors that were previously challenging to reconstruct. My research focuses on employing bone histology to explore the life and adaptive processes of large vertebrates, such as dinosaurs and mammals. Specifically, I aim to uncover what factors influenced these creatures to evolve into giants or diminutive forms and how terrestrial vertebrates altered their physiology and bone structure to successfully readapt to aquatic environments.

I have interests in parental care and sexual conflicts over reproduction in teleost fishes. My goal is to understand social relationship among individuals by approaching the field researches and observations in lab conditions, from evorutionary views. In the resent years, I also conduct some field works to examine a composition of food-webs in aquatic ecosystem and evaluate the relationships between biodiversity of aquatic animals (e.g. dragonflies) and their local and landscape habitats.

The radius of Earth is 6371 km, whereas the deepest borehole ever drilled reached only 12 km (0.2% of Earth radius) into Earth. It can be said that Earth’s deep interior is the place further than the universe. We analyze the seismic wave and explore the deep interior of the earth which can’t be seen directly. By analyzing propagation of the seismic wave, we investigate the temperature and the existence of magma and/or fluid, and we consider the dynamics of the Earth.

The Upper Paleolithic age of the Japanese archipelago is represented as blade based industries, and there are close relationships between blade production techniques and the beginning of the Upper Paleolithic age. Furthermore, the “knife-shaped tool” is one of the typical formal tool types of the blade industry in the Japanese archipelago. For the Initial Upper Paleolithic period when the blade technology was not yet fully established, a set of technique was also confirmed which utilized flakes and vertical elongated flakes. Although various chronological hypotheses of the EUP were so far presented, they have not been unified yet.
I rethink the Early Upper Paleolithic industries in the Japanese Archipelago and East Asia throught the method of Usewear analysis and Traceology.

Animal bones typically contain growth marks, similar to those of tree rings. Previous studies have utilized these marks to reconstruct the growth of extinct animals, especially dinosaurs, and further investigate their physiology and ecology. Using specimens and data that I have collected through fieldwork and museum visits all over the world, I hope to contribute to our understanding of the link between life histories of fossil animals and macroevolutionary patterns.