Abstract
Maternal age can have contrasting effects on a variety of offspring fitness traits. While the effects of maternal age on offspring traits that are not sex-specific, such as body size and growth rate, as well as on traits specific to females, have been well researched, traits that are specific to male offspring have been understudied. Across taxa, male reproductive investment is a particularly salient component of fitness, especially when females mate with several males. We tested whether maternal age affects the reproductive traits of their male offspring by comparing the investment made by male field crickets, Teleogryllus oceanicus, from ‘young’ and ‘old’ maternal age treatments. Female T. oceanicus mate with several males, and sperm competition is a fair lottery, so male reproductive investment is important for fitness in this system. After two generations of mating young and old females, we measured the testes mass, spermatophore mold mass, and sperm viability of their male offspring. Despite differences in maternal and grand-maternal age and the demonstrated effects of advanced maternal age on egg number and offspring immunocompetency in this system, the male offspring of young and old females did not differ in reproductive tissues and sperm viability. This study is one of the first to examine the effect of maternal age on fitness-related traits specific to male offspring, and we encourage future research that tests the effects of maternal age on male offspring in other species.
Highlights
Intrinsic characteristics of parents and their experiences through life can have profound effects on offspring traits through parental effects
We found that maternal age treatment did not affect the reproductive traits of male offspring
We asked whether advanced maternal age influenced the reproductive traits of male offspring and found no influence of maternal age treatment on testes mass, spermatophore mold mass, or sperm viability; our sperm viability results should be viewed cautiously due to our unbalanced sample size for that portion of the experiment
Summary
Intrinsic characteristics of parents and their experiences through life can have profound effects on offspring traits through parental effects (reviewed in Badyaev and Uller 2009). The effects of parental age on the traits of the offspring are not consistent across studies and can be positive, negative, or neutral. The effects of advanced parental age on offspring fitness typically support one of two major bodies of literature: life history theory or aging theory. Even if females of advanced age invest heavily in their offspring (terminal investment), consistent with life-history theory, limited resources late in life may mean that that investment is lower than investments made at younger ages. Is that there may be no change in maternal investment with maternal age Both the terminal investment literature and aging literature have traditionally focused on the effects of advanced parental age on traits that are relevant to both sexes (such as body size or growth rate) or investigated fitness effects only for female offspring
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call