No evidence of predation causing female-biased sex ratios in marine pelagic copepods

Mendes Gusmão, Luiz Felipe, McKinnon, A. David and Richardson, Anthony J. (2013) No evidence of predation causing female-biased sex ratios in marine pelagic copepods. Marine Ecology: Progress Series, 482 279-298. doi:10.3354/meps10265

Author Mendes Gusmão, Luiz Felipe
McKinnon, A. David
Richardson, Anthony J.
Title No evidence of predation causing female-biased sex ratios in marine pelagic copepods
Journal name Marine Ecology: Progress Series   Check publisher's open access policy
ISSN 0171-8630
Publication date 2013-01
Sub-type Critical review of research, literature review, critical commentary
DOI 10.3354/meps10265
Open Access Status DOI
Volume 482
Start page 279
End page 298
Total pages 20
Place of publication Oldendorf, Germany
Publisher Inter-Research
Collection year 2014
Language eng
Formatted abstract
Although sex ratios close to unity are expected in dioecious species, biased sex ratios are common in nature. It is essential to understand causes of skewed sex ratios in situ, as they can lead to mate limitation and have implications for the success of natural populations. Female-skewed sex ratios are commonly observed in copepods in situ. Here we discuss the challenges of copepod sex ratio research and provide a critical review of factors determining copepod sex ratios, focusing on 2 main objectives. The first is a critique of the male predation theory, which is currently the main process thought to be responsible for female-skewed sex ratios. It assumes that males have higher mortality because of increased vulnerability to predation during their search for mates. We show that there is little support for the male predation theory, that sex ratios skewed toward females occur in the absence of predation, that sex ratios are not related to predation pressure, and that where sex-skewed predation does occur, it is biased toward females. Our second objective is to suggest alternative hypotheses regarding the determination of sex ratios. We demonstrate that environmental factors, environmental sex determination and sex change have strong effects on copepod sex ratios, and suggest that differential physiological longevity of males and females may be more important in determining sex ratios than previously thought. We suggest that copepod sex ratios are the result of a mixture of factors.
Keyword Sex-specific predation
Sex change
Environmental sex determination
Prey size
Sex ratio
Chaetognath Sagitta-elegans
Prey size spectra
Selective predation
Stocking density
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Critical review of research, literature review, critical commentary
Collections: School of Mathematics and Physics
Official 2014 Collection
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Citation counts: TR Web of Science Citation Count  Cited 5 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 6 times in Scopus Article | Citations
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