Males more considerate than imagined

At least, in nematode worms

2010-11-02

(Press-News.org) Male worms plug females after copulation as a form of 'gift', rather than to prevent them from mating again, as had previously been thought. Researchers writing in BioMed Central's open access journal Frontiers in Zoology found that plugged females mated just as often and were just as attractive as those who were unplugged, and that plugging ultimately improved female fitness.

Nadine Timmermeyer worked with a team of researchers from the University of Tuebingen, Germany, to investigate the effects of copulatory plugs in the nematode worm Caenorhabditis remanei. She said, "Our results indicate that plugging neither affects the likelihood that a female is located by males, nor whether or not mating ensues. However, we found that plugging has a significant positive effect on egg production, suggesting that plugs may represent a beneficial act of a male towards its female partner rather than a competitive act between males".

Mating plugs have been documented for a broad range of animal groups, including insects, arachnids, reptiles, and rodents. In the worms studied, plugs consist of gelatinous mass deposited by the male onto the female's vulva at the end of copulation, which then hardens like glue. Speaking about possible ways that such a seal may benefit both males and females, Timmermeyer said "A plug may act as a seal, keeping sperm inside the female and preventing the entry of harmful pathogens. It may also contain substances that stimulate the female, or that have nutritious or antimicrobial properties".

### Notes to Editors

1. The function of copulatory plugs in Caenorhabditis remanei: hints for female benefits
Nadine Timmermeyer, Tobias Gerlach, Christian Guempel, Johanna Knoche, Jens F Pfann, Daniel Schliessmann and Nico K Michiels
Frontiers in Zoology (in press)

During embargo, article available here: http://www.frontiersinzoology.com/imedia/1540767028411889_article.pdf?random=395530

After the embargo, article available at the journal website: http://www.frontiersinzoology.com/

Please name the journal in any story you write. If you are writing for the web, please link to the article. All articles are available free of charge, according to BioMed Central's open access policy.

Article citation and URL available on request at press@biomedcentral.com on the day of publication.

2. Frontiers in Zoology is an Open Access, peer-reviewed, online journal publishing high quality research articles and reviews on all aspects of animal life.

3. BioMed Central (http://www.biomedcentral.com/) is an STM (Science, Technology and Medicine) publisher which has pioneered the open access publishing model. All peer-reviewed research articles published by BioMed Central are made immediately and freely accessible online, and are licensed to allow redistribution and reuse. BioMed Central is part of Springer Science+Business Media, a leading global publisher in the STM sector.

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