Research Laboratories

Research Laboratories
SYSTEMATIC BOTANY (Koji Takayama and Hidetoshi Kato)

SYSTEMATIC BOTANY (Koji Takayama and Hidetoshi Kato)

Research Overview

Our research aims to elucidate the diversity, evolutionary history, and speciation processes of land plants. We emphasize fieldwork for specimen collection and investigating, integrating these efforts with molecular biology, cytology, and morphological analyses in the laboratory to achieve a comprehensive understanding of plant diversity. Additionally, we manage and maintain the plant specimen repository housed at the Makino Herbarium (MAK).

If you are interested in joining our graduate program and conducting research with us, please contact us via email.

Current Projects

(1) Taxonomy, Phylogeny, and Evolution of Land Plants

An estimated 300,000 species of land plants inhabit our planet. Our laboratory aims to understand their evolutionary relationships, how they are interconnected in nature, and the mechanisms driving their evolution and diversification. Using a diverse collection of plant specimens from field surveys, we conduct comparative morphological analyses, DNA sequencing, chromosome and genome size comparisons, and ecological data collection. By integrating these approaches, we seek to unravel the complex processes of plant diversity and evolution, deepening our understanding of evolutionary phenomena.

(2) Phylogeography of Terrestrial Plants

Each land plant species has a unique geographical distribution. Phylogeography investigates how their distributions have been shaped over time using genetic variation within and between species. Our research focuses on analyzing genetic diversity at the DNA sequence level to elucidate historical shifts in plant distribution. By comparing taxa that have similar distribution patterns, we identify commonalities and differences in their geographic histories. We also explore phylogeographic structures in relation to ecological relationships between different organisms. Through these studies, we aim to clarify the connections between species interactions and their geographic distributions.

(3) Diversification of Floral Morphology and Reproductive Strategies

Angiosperms, the most successful group of plants on Earth, have co-evolved with pollinators (e.g. insects) which ultimately influence the evolution of floral morphology. Furthermore, plants exhibit a diverse array of sexual expressions and mating systems across different taxa. Our research investigates plant-pollinator interactions through field observations of floral visitors, controlled experiments in experimental fields, and anatomical and physiological analyses in the laboratory. Through these studies, we aim to uncover the evolutionary mechanisms driving the diversification of reproductive strategies in plants.

(4) Plant Evolution and Conservation on Oceanic Islands

Oceanic islands have long been regarded as natural laboratories of evolution, attracting the interest of biologists from past to present. Our research focuses on the evolutionary processes that gave rise to the endemic plants of these islands, particularly those if the Ogasawara islands. We investigate the origins and evolutionary pathways of the unique flora. In recent decades, climate change and human activity have significantly impacted the islands’ nature, putting many native plant species at risk of extinction. By studying their characteristics and distribution patterns, we aim to contribute to the conservation of oceanic island ecosystems.

(5) Flora Surveys and Regional Plant Diversity

The term "flora" refers to the collection of plant species inhabiting a specific region. While extensive research has been conducted in some areas, many parts of the world still lack comprehensive floristic studies. As biodiversity loss accelerates, documenting plant species has become an urgent and critical task.
Our team is currently conducting a floristic survey of Tokyo Prefecture. Despite being one of the world's largest metropolitan areas, Tokyo encompasses a wide range of natural environments, from the subalpine and cool temperate zones of Okutama to the warm temperate and subtropical regions of the Izu and Ogasawara Islands. We conduct field surveys across these diverse regions, collecting plant specimens and deposit them in the Makino Herbarium. Through this work, we analyze the composition and characteristics of regional flora while also monitoring changes in Tokyo's natural environment.

Staff Highlight


Dr. Koji Takayama (髙山浩司) Professor	Dr. Hidetoshi Kato (加藤英寿) Assistant Professor
Email:
takayamak[at]tmu.ac.jp	katohide[at]tmu.ac.jp
Read more:
(Researchgate Profile) (ResearchMap Profile) (TMU Faculty Profile (Japanese))	(Researchgate Profile) (ResearchMap Profile) (TMU Faculty Profile (Japanese))
Lab Information: Department Laboratory Page (English) (Japanese)

Recent Publications

1. (3063) Proposal to conserve the name Talipariti against Papuodendron (Malvaceae)

Laurence J. Dorr, Koji Takayama, Fernando Vélez‐Esperilla. Taxon, Jan 2025

2. 1110. Hibiscus glaber Matsum. ex Nakai

Fernando Vélez‐Esperilla, Koji Takayama, Minako Takegami, Masumi Yamanaka. Curtis's Botanical Magazine,

41(3) 331-340, Sep 2024

3. Genetic Characteristics of Elaeocarpus photiniifolia (Elaeocarpaceae) in the Dry Scrub of the Hahajima Islands

Kyoko Sugai, Akane Ito, Suzuki Setsuko, Noriaki Murakami, Hidetoshi Kato. Acta Phytotaxonomica et Geobotanica,

75(2) 71-83, Jun 2024

4. “Alstroemeria maxima (Alstroemeriaceae, Alstroemerieae), a hidden giant” revealed through integrative taxonomy

Nicolás I. Villalobos, Carlos M. Baeza, Víctor L. Finot, Óscar Toro-Núñez, Eduardo Ruiz-Ponce, Koji Takayama,

Hiroshi Noda, Gonzalo A. Collado, Freddy Mora-Poblete. Brazilian Journal of Botany, 47 649–669 May 2024

5. Ecotype variation in the endemic tree Callicarpa subpubescens on small oceanic islands: genetic, phenotypic, and environmental insights

Suzuki Setsuko, Kyoko Sugai, Ichiro Tamaki, Kayo Hayama, Hidetoshi Kato. Heredity, 132 309–319, May 2024

See more: (ResearchMap)

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