The impact of ageing on male reproductive success in Drosophila melanogaster

Abstract

Male reproductive ageing has been mainly explained by a reduction in sperm quality with negative effects on offspring development and quality. In addition to sperm, males transfer seminal fluid proteins (Sfps) at mating; Sfps are important determinants of male reproductive success. Receipt of Sfps leads to female post-mating changes including physiological changes, and affects sperm competition dynamics. Using the fruit fly Drosophila melanogaster we studied ageing males' ability to induce female post-mating responses and determined the consequences of male ageing on their reproductive success. We aged males for up to 7weeks and assayed their ability to: i) gain a mating, ii) induce egg-laying and produce offspring, iii) prevent females from remating and iv) transfer sperm and elicit storage after a single mating. We found that with increasing age, males were less able to induce post-mating responses in their mates; moreover ageing had negative consequences for male success in competitive situations. Our findings indicate that with advancing age male flies transferred less effective ejaculates and that Sfp composition might change over a male's lifetime in quantity and/or quality, significantly affecting his reproductive success.

Social behavior and aging: A fly model

“…As in other animals, sex differences in aging, lifespan, 14,88 reproductive traits, [108][109][110][111][112] and transgenerational effects have been reported in D. melanogaster. 111,113,114 Like other animals, rapid reproduction in early life reduces longevity in D. melanogaster, as resources invested in reproduction can come at the cost of organismal longevity.…”

Sex ratio at mating does not modulate age fitness effects in Drosophila melanogaster

“…More recent studies have further investigated how female and male age can decrease offspring viability by focusing on underlying pre‐ and postmeiotic aging processes (Firman, Young, Rowe, Duong, & Gasparini, ; Pizzari et al, ; Tan, Pizzari, & Wigby, ). In short, the effects of age on reproductive success have been relatively well explored, yet most available studies have overlooked how socio‐sexual factors such as density or sex ratio might modulate reproductive senescence across the sexes (Brengdahl, Kimber, Maguire‐Baxter, Malacrinò, & Friberg, ; Carazo, Molina‐Vila, & Font, ; Fricke, Green, Mills, & Chapman, ; Ruhmann, Koppik, Wolfner, & Fricke, ; Tan et al, ; Zhao, Xuan, Li, & Xi, ).…”

IsDrosophila melanogasterStress Odorant (dSO) really an alarm pheromone?

“…Similarly, the absence of an age-related response to dSO in females is not surprising for although the highest daily egg output occurs during the first week (Tatar, Promislow, Khazaeli, & Curtsinger, 1996), moving away from potential danger could extend her future opportunities to oviposit. In contrast, as mating opportunities for males decline with age (see Ruhmann, Koppik, Wolfner, & Fricke, 2018) older males would have less to lose than younger ones with respect to future reproduction.…”