| Project/Area Number |
11440229
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
生態
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| Research Institution | CHUKYO UNIVERSITY |
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Principal Investigator |
KUWAMURA Tetsuo Chukyo Univ., Facultyof Liberal Arts, Professor, 教養部, 教授 (00139974)
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| Co-Investigator(Kenkyū-buntansha) |
KARINO Kenji Tokyo Gakugei University, Department of Biology, Associate Professor, 教育学部, 助教授 (40293005)
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| Project Period (FY) |
1999 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥9,500,000 (Direct Cost: ¥9,500,000)
Fiscal Year 2001: ¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 2000: ¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1999: ¥4,700,000 (Direct Cost: ¥4,700,000)
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| Keywords | Fish / Social system / Sex / Reproductive behavior / Sex change / Behavioral ecology / Evolutionary biology |
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| Research Abstract |
Field and aquarium experiments were carried out in order to investigate relationships between social/mating systems and sex allocation among several fish species on coral reefs of Sesoko Island, Okinawa and rocky reefs of Izu Peninsula. The following relationships were found.
1. In the monogamous and protandrous anemone fishes Amphiprion spp., experiments keeping 2 females have been conducted, but female-to-male sex change has not yet been confirmed. The experiments will be continued.
2. In the haremic and protogynous wrase Labroides dimidiatus and angel fish Centropyge ferrugatus, when males that had lost their mates met together, the smaller male changed back to female as it became subordinate.
3. in the haremic trigger fish Sufflamen chrysopterus, we found female-tomale sex change by male removal experiments. Smaller, nonterritorial males were also found, and it is unknown whether males change back to females.
4. In the polygamous and protogynous wrasse Halichoeres melanurus, goby Plerosicya muscarum and damselfish Dascyllus aruanus, males did not change back to female probably because subordinate smaller males have also opportunities to get reproductive success.
5. In the polygamous goby Bathygobius fuscus and damselfish Dascyllus trimaculatus, we found no sign of sex change in such male-territory-visiting mating systems.
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