Demary Kristian C
Biology Department, Tufts University, Medford, MA 02155, USA.
J Insect Physiol. 2005 Jul;51(7):837-41. doi: 10.1016/j.jinsphys.2005.04.001.
In many species females mate with and store sperm from multiple males, and some female insects have evolved multiple compartments for sperm storage. Sperm storage and sperm viability were investigated in two firefly species, Photinus greeni and P. ignitus, which differ in the morphology of the female reproductive tract. Although the primary spermatheca is similar in both species, P. greeni females have an additional, conspicuous outpocketing within the bursa copulatrix whose potential role in sperm storage was investigated in this study. An assay that distinguishes between live and dead sperm was used to examine sperm viability in male seminal vesicles and sperm storage sites within the female reproductive tract. For both Photinus species, sperm from male seminal vesicles showed significantly higher viability compared to sperm from the primary spermatheca of single mated females. In single mated P. greeni females, sperm taken from the channel outpocketing (secondary spermatheca) showed significantly higher viability compared to sperm from the primary spermatheca. This sperm viability difference was not evident in double mated females. There were no significant differences between P. greeni and P. ignitus females in the viability of sperm from the primary spermatheca. These studies contribute to our understanding of post-mating processes that may influence paternity success, and suggest that sexual conflict over control of fertilizations may occur in multiply mated firefly females.
在许多物种中，雌性会与多个雄性交配并储存它们的精子，一些雌性昆虫已经进化出多个精子储存区室。对绿胸萤和北美萤火虫这两种萤火虫进行了精子储存和精子活力的研究，它们的雌性生殖道形态有所不同。尽管两种萤火虫的主受精囊相似，但绿胸萤雌性在交配囊内还有一个额外的明显袋状结构，本研究对其在精子储存中的潜在作用进行了调查。使用一种区分活精子和死精子的检测方法，来检查雄性精囊中以及雌性生殖道内精子储存部位的精子活力。对于这两种萤火虫，来自雄性精囊的精子活力明显高于单次交配雌性主受精囊中的精子。在单次交配的绿胸萤雌性中，从通道袋状结构（副受精囊）取出的精子活力明显高于主受精囊中的精子。在多次交配的雌性中，这种精子活力差异并不明显。绿胸萤和北美萤火虫雌性主受精囊中精子的活力没有显著差异。这些研究有助于我们理解可能影响父权成功的交配后过程，并表明在多次交配的萤火虫雌性中可能发生受精控制权方面的性冲突。
