Environmental factors influencing adult sex ratio in Poecilia reticulata: laboratory experiments

McKellar, Ann E.; Hendry, Andrew P.

doi:10.1111/j.1095-8649.2011.03065.x

Cited by 11 publications

(10 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Even if all migrants were male, this level of migration would shift a sex ratio of 0.5 to just 0.475, thus mortality is likely much more important than migration. Others (Seghers and McKellar et al ) have suggested that males are more vulnerable to predators, especially R. hartii , and that this is key in explaining female‐biased sex ratios because this predator preferentially feeds on male guppies in the laboratory (McKellar and Hendry ). Predation likely contributes to male mortality but cannot explain why temporal variation in adult sex ratio is correlated among our populations.…”

Section: Discussionmentioning

confidence: 99%

REPLICATED ORIGIN OF FEMALE-BIASED ADULT SEX RATIO IN INTRODUCED POPULATIONS OF THE TRINIDADIAN GUPPY (POECILIA RETICULATA)

2014

View full text Add to dashboard Cite

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, affecting 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 femalebiased sex ratio arises predictably and is a consequence of higher male mortality and longer female life spans 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. K E Y W O R D S :Life span, mark-recapture, population structure, sex-biased mortality, sex-biased recruitment, sex-ratio.

show abstract

Section: Discussionmentioning

confidence: 99%

REPLICATED ORIGIN OF FEMALE-BIASED ADULT SEX RATIO IN INTRODUCED POPULATIONS OF THE TRINIDADIAN GUPPY (POECILIA RETICULATA)

2014

View full text Add to dashboard Cite

show abstract

“…Male guppies appear to be more sensitive to high temperatures than females; thus, temperature differences between sites are expected to impact upon the ASR (Pettersson et al ., ). In addition, with males being more colourful and active than females, the males are predated more often than the females by one predator (killifish Rivulus hartii ) but not by another (freshwater prawn Macrobrachium crenulatum ; McKellar & Hendry, ). Therefore, variation in predator densities between streams may also contribute to ASR variation (McKellar & Hendry, ).…”

Section: Spatial and Temporal Variation In Adult Sex Ratiosmentioning

confidence: 99%

Adult sex ratio variation: implications for breeding system evolution

Székely

Weissing

Komdeur

2014

J of Evolutionary Biology

200

229

View full text Add to dashboard Cite

Adult sex ratio (ASR) exhibits immense variation in nature, although neither the causes nor the implications of this variation are fully understood. According to theory, the ASR is expected to influence sex roles and breeding systems, as the rarer sex in the population has more potential partners to mate with than the more common sex. Changes in mate choice, mating systems and parental care suggest that the ASR does influence breeding behaviour, although there is a need for more tests, especially experimental ones. In the context of breeding system evolution, the focus is currently on operational sex ratios (OSRs). We argue that the ASR plays a role of similar importance and urge researchers to study the ASR and the OSR side by side. Finally, we plead for a dynamic view of breeding system evolution with feedbacks between mating, parenting, OSR and ASR on both ecological and evolutionary time scales.The great importance of the adult sex ratio has long been recognized by the student of human populations, but it has not received as much attention from the animal biologist as it deserves.

show abstract

“…Concerning sex differences in vulnerability to predators, mixed results were found. In a laboratory study, male guppies suffered higher mortality rates from a piscine predator (McKellar & Hendry 2011). However, a recent mark and recapture study has suggested that the female-biased sex ratio commonly observed in natural populations is unlikely to be explained by a greater male vulnerability to predators but rather by environmental factors such as seasonal variability in resources (Arendt et al 2014).…”

Section: Introductionmentioning

confidence: 96%

Sex Differences in Discrimination of Shoal Size in the Guppy (Poecilia reticulata)

2016

View full text Add to dashboard Cite

For a diversity of species, differences in sexual and parental roles, along with differences in body morphology, often result in males and females having different diets, distinct predators and even different patterns of habitat use. As a consequence, the two sexes often face different environmental challenges and selection may favour the evolution of sex differences in cognition. We tested this prediction in the guppy (Poecilia reticulata). Under perceived hazard, individual guppies join the larger available social group, a behaviour that is thought to minimise predation risk. In this species, females are more frequently exposed to predation and more averse to predation risk; we therefore expected greater accuracy in shoal size discrimination in females. We compared the accuracy of male and female guppies in discriminating shoals of 4 and 6 conspecifics, which represents the upper limit of discrimination for this species. Overall, we found no sex differences in the accuracy of discriminating the two shoals. However, while females showed this ability at the beginning of the test, males began to select the larger group only after several minutes. In three control experiments, we found indications that this sex difference cannot be accounted for by differences in motivation or antipredator strategies between the two sexes, suggesting female guppies are more efficient at rapidly estimating shoal size.

show abstract

Environmental factors influencing adult sex ratio in Poecilia reticulata: laboratory experiments

Cited by 11 publications

References 67 publications

REPLICATED ORIGIN OF FEMALE-BIASED ADULT SEX RATIO IN INTRODUCED POPULATIONS OF THE TRINIDADIAN GUPPY (POECILIA RETICULATA)

REPLICATED ORIGIN OF FEMALE-BIASED ADULT SEX RATIO IN INTRODUCED POPULATIONS OF THE TRINIDADIAN GUPPY (POECILIA RETICULATA)

Adult sex ratio variation: implications for breeding system evolution

Sex Differences in Discrimination of Shoal Size in the Guppy (Poecilia reticulata)

Contact Info

Product

Resources

About