Department of Biology, Graduate School of Science and Technology, Shinshu University, Matsumoto, Nagano 390-8621, Japan.
Department of Biology, Faculty of Science, Shinshu University, Matsumoto, Nagano 390-8621, Japan,
Zoolog Sci. 2021 Feb;38(1):20-25. doi: 10.2108/zs200098.
Oviparous, ovoviviparous and viviparous reproduction are interesting subjects for understanding animals' evolutionary pathways and adaptation to their life history and habitat conditions. In this study, we examined the reproductive mode of the ovoviviparous mayfly , particularly comparing embryogenesis between hand-pairing and unmated females' common oviduct. Our study suggested that the high developmental rate of observed in a recent study could be ascribed to their absorption of unfertilized eggs. The developmental rates of hand-paired females were almost 100%, while their egg-bearing numbers were lower than those of virgin females. Thus, such reduced egg numbers suggest the maternal absorption of unfertilized eggs. This trait is thought to have evolved with the ovoviviparous characteristics of . We identified the basis of the irregularity of this species exhibiting such a high (i.e., 100%) developmental rate in our previous recent study.
卵生、卵胎生和胎生繁殖是了解动物进化途径和适应其生活史和栖息地条件的有趣主题。在这项研究中，我们研究了卵胎生的蜉蝣的繁殖模式，特别是比较了手配对和未交配的雌性普通输卵管中的胚胎发生。我们的研究表明，在最近的一项研究中观察到的高发育率可能归因于它们吸收未受精卵。手配对雌性的发育率几乎为 100%，但其产卵数低于处女雌性。因此，这种减少的产卵数表明母体吸收了未受精卵。这种特性被认为是随着卵胎生特征的进化而来的。我们在之前的一项研究中确定了这种不规则性的基础，这种不规则性表现出如此高（即 100%）的发育率。
