Environmental Biology of Fishes

, Volume 46, Issue 3, pp 281–288

Both-ways sex change in monogamous coral gobies, Gobiodon spp.

Authors

  • Yasuhiro Nakashima
    • Department of Zoology, Faculty of ScienceKyoto University
  • Tetsuo Kuwamura
    • Biological Laboratory, Faculty of Liberal ArtsChukyo University
  • Yutaka Yogo
    • Showa Women's High School
Article

DOI: 10.1007/BF00005004

Cite this article as:
Nakashima, Y., Kuwamura, T. & Yogo, Y. Environ Biol Fish (1996) 46: 281. doi:10.1007/BF00005004

Synopsis

We confirmed both-ways sex change in the coral-dwelling gobies Gobiodon micropus, G. oculolineatus, G. quinquestrigatus and G. rivulatus rivulatus by mate-removal experiment in the field and by the aquarium experiment of keeping two consexual fish in a coral. Eight species of Gobiodon were found in Acropora corals on the reef flat of Sesoko Island, Okinawa, southern Japan. The 4 species mentioned above bred in monogamous pairs composed of a male and a female matched by size, and the male took care of eggs deposited on the coral branch. In G. quinquestrigatus and G. rivulatus rivulatus males were larger than females in newly formed pairs, and females grew faster than their mates until breeding. The growth-rate advantage in females seems to be the major factor in the evolution of female to male sex change. The gobies strongly depended on host corals, but they moved between the corals after mate loss or coral death to form new pairs. This provides opportunities for the evolution of male to female sex change; the ability to change sex in both directions reduces the frequency of risky movement between host corals to form new pairs. These conditions are very similar to those reported in the both-ways sex change of another coral-dwelling goby Paragobiodon echinocephalus.

Key words

HermaphroditismProtandryProtogynyGrowth-rate advantageInter-group movementMonogamyParental careGobiidae

Copyright information

© Kluwer Academic Publishers 1996