Skip Navigation

Integrative and Comparative Biology 2005 45(1):39-42; doi:10.1093/icb/45.1.39
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (3)
Right arrow Request Permissions
Google Scholar
Right arrow Articles by Ayaki, T.
Right arrow Articles by Arizono, K.
Right arrow Search for Related Content
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

The Society for Integrative and Comparative Biology

Sexual Disruption in the Freshwater Crab (Geothelphusa dehaani)1

Toshikazu Ayaki1, Yoshiharu Kawauchino2, Chihiro Nishimura1, Hiroshi Ishibashi3 and Koji Arizono2,3
1 Nagasaki Prefectural University, 123 Kawashimo-cho, Sasebo City, 858-8580, Nagasaki, Japan
2 Sasebo Public Health Center, 5-17 Takasago-cho, Sasebo City, 857-0042, Nakasaki, Japan
3 Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto City 862-8502, Kumamoto, Japan

To clarify the effect of environmental endocrine disruptors on the induction of secondary sexual characteristics in wild animals, we observed 1,527 male and 1,847 female specimens of sexually mature Japanese freshwater crabs, Geothelphusa dehaani, collected at 12 sample points from 10 rivers in Sasebo City, Nagasaki Prefecture, Japan. The results obtained were as follows:

  1. Abnormal males, with external appearance of a complete male, but having female genital openings, were observed at frequencies of 8–32% of males collected at all sample points. In contrast to this, all females collected were normal.
  2. The frequency of abnormal males increased significantly with the increase in individual carapace width.

This species inhabits mountain streams in Japan, which are free from tributyltin that is known to induce the sexual mosaic phenomenon in mollusks. The streams are most likely polluted by some agricultural chemicals and chemicals present in waste gases from cars and especially particulate materials from diesel engines. The clear relationship of the frequencies of abnormal males to size (or age) suggests that the sexual mosaic phenomenon is induced not only at early stages of male development but after sexual maturation, in response to long-term exposure to chemical(s) during the whole life cycle of males. The definitive causal factors and mechanisms inducing sexual mosaics in this species are still unclear.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 J HeredHome page
C. Curtis, B. S. Stewart, and S. A. Karl
Sexing Pinnipeds with ZFX and ZFY Loci
J. Hered., June 4, 2007; (2007) esm023v1.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.