Female influence over offspring paternity in the red flour beetleTribolium castaneum

Abstract

In animals having internal fertilization, both sexes can potentially influence the post-copulatory processes of sperm transfer, sperm storage and sperm use for fertilization. In this experiment, we investigated whether Tribolium castaneum females can influence male paternity success following consecutive matings with two different males. We compared second male paternity success (P 2 ) between females exposed to carbon dioxide (CO 2 ) and control females kept in air, in both cases for 30 min between two matings. CO 2 exposure inhibits muscular activity and has previously been shown to decrease sperm storage by T. castaneum females. Females exposed to CO 2 after their first mating showed significantly higher P 2 than control females during the later portion of a one-month oviposition period. These results are consistent with reduced storage of first male sperm by CO 2 -exposed females. Also, T. castaneum females showed considerable variation in spermathecal morphology, and P 2 decreased with increasing spermathecal tubule volume. These results demonstrate that T. castaneum females can influence male paternity success, and suggest that differential sperm storage may be an important mechanism of post-copulatory female choice.

Experiments with genitalia: a commentary

“…Some explanations of differences in the numbers of sperm being transferred to the female as a [25,45] have ignored the possibility that female changes (e.g. in the volume of the structure into which males must transfer sperm [46], or the conditions under which the female does or does not transport sperm to storage and fertilization sites [47]) might have driven divergence in males. As noted by Wedell and Hosken [48] 'females are the arenas in which postcopulatory sexual selection occurs, so at some fundamental level they are always involved passively or otherwise'.…”

An Analytical Framework for Estimating Fertilization Bias and the Fertilization Set from Multiple Sperm-Storage Organs

“…Indeed, the closer we get to fertilization, the less we understand about the mechanisms of cryptic female choice. Thus, we know more about female-mediated processes influencing intromission (e.g., Brennan et al 2007), sperm transfer (e.g., Sakaluk and Eggert 1996;Pilastro et al 2004;Bussière et al 2006;Hall et al 2010), and retention of sperm (e.g., Bishop et al 1996;Pizzari and Birkhead 2000;Dean et al 2011;Lüpold et al 2012) than we do about sperm storage and use for fertilization (e.g., Ward 1993;Otronen et al 1997;Có rdoba-Aguilar 1999;Fedina and Lewis 2004;Pattarini et al 2006).…”

Conspecific Sperm Precedence in Two Species of Tropical Sea Urchins

“…In some cases, females affect fertilization by muscular control of sperm position within the reproductive tract (Fedina and Lewis 2004) or expulsion of sperm from the tract (Wagner et al 2004). Other cases involve compatibility of genitalia or gamete morphology (Eberhard 1996).…”