0000000000984386
AUTHOR
Zahida Sultanova
Condition‐dependent mortality exacerbates male (but not female) reproductive senescence and the potential for sexual conflict
Disentangling the relationship between age and reproduction is central to understand life-history evolution, and recent evidence shows that considering condition-dependent mortality is a crucial piece of this puzzle. For example, nonrandom mortality of 'low-condition' individuals can lead to an increase in average lifespan. However, selective disappearance of such low-condition individuals may also affect reproductive senescence at the population level due to trade-offs between physiological functions related to survival/lifespan and the maintenance of reproductive functions. Here, we address the idea that condition-dependent extrinsic mortality (i.e. simulated predation) may increase the a…
Sex ratio at mating does not modulate age fitness effects in Drosophila melanogaster
Abstract Understanding the effects of male and female age on reproductive success is vital to explain the evolution of life history traits and sex‐specific aging. A general prediction is that pre‐/postmeiotic aging processes will lead to a decline in the pre‐ and postcopulatory abilities of both males and females. However, in as much the sexes have different strategies to optimize their fitness, the decline of reproductive success late in life can be modulated by social context, such as sex ratio, in a sex‐specific manner. In this study, we used Drosophila melanogaster to investigate whether sex ratio at mating modulates age effects on male and female reproductive success. As expected, male…
Perception costs of reproduction can magnify sexual selection
We outline two avenues for future research:(1) in model organisms (for example, D. melanogaster), manipulating perception costs in males of varying quality and subsequently testing whether this results in an increase or decrease of male fitness variance; and (2) comparing short-term (that is, no perception costs) versus long-term estimations of male fitness variance in single cohorts via meta-analysis or ad hoc behavioural experiments.
Genetic sex determination and sex-specific lifespan in tetrapods – evidence of a toxic Y effect
ABSTRACTSex-specific lifespans are ubiquitous across the tree of life and exhibit broad taxonomic patterns that remain a puzzle, such as males living longer than females in birds and vice versa in mammals. The prevailing “unguarded-X” hypothesis (UXh) explains this by differential expression of recessive mutations in the X/Z chromosome of the heterogametic sex (e.g., females in birds and males in mammals), but has only received indirect support to date. An alternative hypothesis is that the accumulation of deleterious mutations and repetitive elements on the Y/W chromosome might lower the survival of the heterogametic sex (“toxic Y” hypothesis). Here, we report lower survival of the heterog…
The “unguarded-X” and the genetic architecture of lifespan: Inbreeding results in a potentially maladaptive sex-specific reduction of female lifespan inDrosophila melanogaster
Sex differences in ageing and lifespan are ubiquitous in nature. The "unguarded-X" hypothesis (UXh) suggests they may be partly due to the expression of recessive mutations in the hemizygous sex chromosomes of the heterogametic sex, which could help explain sex-specific ageing in a broad array of taxa. A prediction central to the UX hypothesis is that inbreeding will decrease the lifespan of the homogametic sex more than the heterogametic sex, because only in the former does inbreeding increase the expression of recessive deleterious mutations. In this study, we test this prediction by examining the effects of inbreeding on the lifespan and fitness of male and female Drosophila melanogaster…
Sex and ageing: A test of evolutionary ideas
Doctoral Program in Biodiversity and Evolutionary Biology.
Data from: The "unguarded-X" and the genetic architecture of lifespan: Inbreeding results in a potentially maladaptive sex-specific reduction of female lifespan in Drosophila melanogaster
Sex differences in ageing and lifespan are ubiquitous in nature. The "unguarded-X” hypothesis (UXh) suggests they may be partly due to the expression of recessive mutations in the hemizygous sex chromosomes of the heterogametic sex, which could help explain sex-specific ageing in a broad array of taxa. A prediction central to the UX hypothesis is that inbreeding will decrease the lifespan of the homogametic sex more than the heterogametic sex, because only in the former does inbreeding increase the expression of recessive deleterious mutations. In this study, we test this prediction by examining the effects of inbreeding on the lifespan and fitness of male and female Drosophila melanogaster…
Data from: Sex ratio at mating does not modulate age fitness effects in D. melanogaster
Understanding the effects of male and female age on reproductive success is vital to explain the evolution of life history traits and sex-specific ageing. A general prediction is that pre/post-meiotic ageing processes will lead to a decline in the pre- and post-copulatory abilities of both males and females. However, inasmuch as sexes have different strategies to optimize their fitness, the decline of reproductive success late in life can be modulated by social context, such as sex ratio, in a sex-specific manner. In this study, we used Drosophila melanogaster to investigate whether sex ratio at mating modulates age effects on male and female reproductive success. As expected, male and fema…