Data from: Replicated origin of female biased adult sex ratio in introduced populations of the Trinidadian guppy (Poecilia reticulata).
Arendt, Jeffrey D., University of California, Riverside
Reznick, David N., University of California, Riverside
López-Sepulcre, Andres, University of Jyväskylä
Published Apr 25, 2014 on Dryad.
Cite this dataset
Arendt, Jeffrey D.; Reznick, David N.; López-Sepulcre, Andres (2014). Data from: Replicated origin of female biased adult sex ratio in introduced populations of the Trinidadian guppy (Poecilia reticulata). [Dataset]. Dryad. https://doi.org/10.5061/dryad.v8d27
There are many theoretical and empirical studies explaining variation in offspring sex ratio but relatively few that explain variation in adult sex ratio. Adult sex ratios are important because biased sex ratios can be a driver of sexual selection and will reduce effective population size which affects population persistence and shapes how populations respond to natural selection. Previous work on guppies (Poecilia reticulata) gives mixed results, usually showing a female-biased adult sex ratio. However a detailed analysis showed that this bias varied dramatically throughout a year and with no consistent sex-bias. We used a mark-recapture approach to examine the origin and consistency of female-biased sex ratio in four replicated introductions. We show that female-biased sex ratio arises predictably and is a consequence of higher male mortality and longer female lifespans with little effect of offspring sex ratio. Inconsistencies with previous studies are likely due to sampling methods and sampling design which should be less of an issue with mark-recapture techniques. Together with other long-term mark-recapture studies, our study suggests that bias in offspring sex ratio rarely contributes to adult sex ratio in vertebrates. Rather, sex differences in adult survival rates and longevity determine vertebrate adult sex ratio.
Monthly guppy sex ratio data
Data for four populations of guppies censused each month since fish were introduced. Includes adult sex ratio (ASR), recruitment sex ratio (RSR), ratio of fish missed in each census (miss), ratio of mortality rates (mort), and average age at death of each sex (M_lifespan, F_lifespan). Also includes 95% confidence intervals derived from Cormack-Jolly-Seber model in POPAN module of the program MARK.