日本語

Tsuyoshi Ito, D.Sc.

Assistant Professor, Department of Evolution and Phylogeny, Primate Research Institute, Kyoto University

Stump tailed macaque geographic variation and modularity of skulls in Japanese macaques Gray langur Ecogeographic variation of skulls Japanese macaque T. Ito Sigiriya, natural habitat of Toque macaque

Research

I have a wide interest in natural history and biodiversity. Currently, I am focusing on the mechanisms and processes underlying morphological diversity in primates. Morphological evolution is not only caused as a response to selection but is also influenced by genetic drift and gene flow. The direction and magnitude of morphological evolution are constrained by genetic and developmental integrations. I strive to understand the whole picture of these evolutionary nature by combining morphometric, genomic, phylogenetic, biogeographic, and paleontological approaches. In particular, I study macaques to understand the subthemes discussed below.

Most of these studies are collaborative works with other research groups including University of the Ryukyus, Ryukoku University, Chulalongkorn University, the Systematics and Phylogeny section, Center for Human Evolution Modeling Research, and Department of Wildlife Science of PRI. Our research can be accomplished thanks to many contributors who collected and preserved specimens and to the funds granted by K-CONNEX (MEXT), KAKEN (JSPS; 11J00120, 15J00134), the Fujiwara Natural History Foundation, University of the Ryukyus, and Primate Research Institute, Kyoto University.

Hybridization

Evolution does not just involves the processes of speciation and divergence but is like a reticulation. Hybridization and genomic admixture provide a novel combination of genes in recombinant descendants, thereby potentially contributing to the novelty and diversity of phenotypes. I examine genome-wide markers (e.g., RAD-Seq) to understand how hybridization and genetic introgression proceed and how they influence morphology. This study originates from a general interest in evolution; however this study could also contribute to the monitoring of invasive species.

Modularity and evolvability

The direction and magnitude of evolution are constrained by genetic and developmental integrations. I apply geometric morphometric and quantitative genetic approaches to understand how the genetic and developmental integrations set limits on the direction of skull evolution and how the evolvability changed in primate evolution.

Genotype–phenotype link

Phenotypic evolution can be caused by genotypic changes; however, the relationship between genotype and phenotype is not like one-to-one correspondence. A gene usually determines multiple traits (pleiotropy), whereas a trait is often caused by the expressions of multiple genes and/or by their interactions (epistasis). I combine association mapping and population/comparative genetics to understand the complex genotype–phenotype networks (multiple-to-multiple relationships) and to understand the genetic backgrounds of phenotypic diversifications.

Phylogenetic and biogeographic diversity

Molecular data have elucidated the phylogenetic relationships of living taxa; however, these data usually cannot extend to extinct taxa with unavailable DNA. Fossils are the only evidence that directly demonstrate the locality and morphology of extinct organisms and are therefore essential for understanding the evolutionary and phylogeographic histories of the studied taxon. I combine molecular and morphometric data to reconstruct the systematics of living and extinct primates.

Publications

Google Scholar Citations

Data

figshare

Collection management

We are in charge of the collection management of vertebrate (especially primate) specimens at Primate Research Institute, Kyoto University. I (like many naturalists) owe much to museum collections, which have been accumulated by many contributors. I would like to reciprocate by collecting and preserving specimens, including both morphological and molecular resources, for future generations.

Outreach

More about me

Activity database on education and research, Kyoto University

Contact

Kanrin 41-2, Inuuyama, Aichi 484-8506, Japan