Hitoshi Araki

Function

• Research scientist and group leader in the research group fisheries genetics
  

Research interests

Academic & research interests

My primary research goal is to understand evolutionary mechanisms of life, which generate and maintain genetic diversities in the wild. Current research interests include evolutionary processes at various levels, with emphasis on their applications to real-world problems. Rapid adaptation of fish to captive environment and conservation of wild populations are two of them. I use population genetic methods as a tool to address these issues. I am also actively involved in molecular evolutionary and genomic studies on many other organisms.

Fish evolution

Fish are one of the best model organisms to address evolutionary questions because of their diversities and adaptive significance. I am particularly interested in the intra-specific genetic diversity in natural fish populations and its maintenance in the evolutionary time frame. It is often surprising how large genetic variation one species can hold even within a population. Mutation and recombination would generate the genetic diversity, but the mechanism for its maintenance is largely unknown. The latter is of my particular interest because the maintenance of the genetic diversity is fundamental to the evolutionary responses to environmental changes in living organisms.

Hatchery stocking and Evolution in captivity

Many populations of a variety of species, including fish species, are sharply declining and/or at the risk of extinction. Fishery scientists have been aware of the issue, and there have been long and extensive discussions on how to deal with it. To date, hatchery stocking is one of the most popular solutions - especially with the great demands for economically valuable species.

However, little is known about the consequence of artificial propagation. Accumulating evidence suggests that the captive-reared fish are genetically and reproductively differentiated from wild fish in a short time range. The question includes a short, demographic consequence of hatchery stocking and rather a long-term, evolutionary consequence of the stocking on declining wild populations. I use theoretical and empirical approaches to address the question.

Current projects

“Rapid Evolution in Captivity (REC)”: This is a SNSF granted project in which we conduct a systematic evaluation of the mechanism of fitness loss in captive-bred brown trout (Salmo trutta).

“River fragmentation and defragmentation”: This is a part of a CCES project (ENHANCE) in which population genetic structure of fish is tested with regard to the fragmentation of Swiss river systems. I am co-supervising Laura Langeloh on this project with Armin Peter. Detailed information of this project is here [...]

 

Curriculum vitae

Professional Experience

2008-present, group leader at Eawag, Kastanienbaum
2006-present, Appointed part-time professor in Nanjing University, China
2004-2007, Postdoctoral research associate in Oregon State University, USA
2001-2004, Postdoctoral fellow in University of Chicago, USA (2002-2003: JSPS research fellow for PD)
1999-2001, JSPS research fellow for DC2 in Kyushu University, Japan

Education

2001, Ph. D. in Kyushu University, Japan (Science, Population Genetics)
1997, M.Sc. in Kyushu University, Japan (Molecular Population Genetics)
1995, B.Sc. in Kyushu University, Japan (Biology)

Award & Appointment

2009, Invitation as a lecturer, University of Bern, Switzerland

2008-present, Invitation to the Editorial Board of the journal Population Ecology

2007, The Award for Encouragement of Research by the Society of Evolutionary Studies, Japan.

2002 – 2003, Invitation as a Research fellow by Japan Society for the Promotion of Science (JSPS-PD)

1999 – 2001, Invitation as a Research fellow by Japan Society for the Promotion of Science (JSPS-DC2)

1997 – 1999, Japan Student Services Organization Type I Fellowship for Ph.D. course students

1995 – 1997, Japan Student Services Organization Type I Fellowship for Master course students

Publications

• Full Publications
  
  
• Eawag Publications