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Updated: Jun 17, 2026

Basic Methods for the Study of Reproductive Ecology of Fish in Aquaria
Published on: July 20, 2017
Sex change in coral reef fish
Masaru Nakamura1, Yasuhisa Kobayashi, Saori Miura
1Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Sesoko 3422, Motobu-cho, Okinawa, 907-0227, Japan, masaru@lab.u-ryukyu.ac.jp.
Abstract:
Gonadal differentiation can take many forms in fish, ranging from gonochorism, where individuals directly develop as male or female and finally possess only testis or ovaries at sexual maturation, to hermaphroditism where the same individuals can produce mature male and female gametes at some time in their lives. Hermaphrodite fish are, thus, an excellent model for studying the plasticity of sex determination and differentiation in vertebrates. We have shown that sex steroids play a principal role in sex differentiation and sex change in fish. Our laboratory implements several fish models that undergo sex change from female to male or male to female or in both directions. In this review, we will briefly discuss recent advances in our understanding of the mechanism of sex change in coral reef fish.
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