Data from: X-ray micro-CT scanning reveals temporal separation of male harm and female kicking during traumatic mating in seed beetles

Dougherty_Simmons_all_data.xlsx (10.40 Kb):
Data on degree of copulatory wounding for all pairs scanned.

Video S1.mpg (86.60 Mb):
3D volume rendering showing a male aedeagus partly everted inside a female during the early stages of mating (pair frozen in copula after 60 seconds of mating, female not shown). The colour represents the relative X-Ray attenuation (brightness) of the tissue, with red representing highest density and blue representing lowest density.

Video S2.mpg (47.67 Mb):
3D volume rendering showing a fully everted male aedeagus inside a female during the early stages of mating (pair frozen in copula after 60 seconds of mating, female not shown). The colour represents the relative X-Ray attenuation (brightness) of the tissue, with red representing highest density and blue representing lowest density.

Video S3.mpg (72.61 Mb):
3D volume rendering showing the interaction between the male aedeagus (colour) and female copulatory tract (greyscale) during the early stages of mating (pair frozen in copula after 60 seconds of mating), viewed from the side. The colours represent the relative X-Ray attenuation (brightness) of the tissue, with red/white representing highest density and blue/dark grey representing lowest density for male and female traits respectively.

In the seed beetle Callosobruchus maculatus, the male intromittent organ is covered in sharp spines that pierce the female copulatory tract wall during mating. Although the fitness consequences of traumatic mating are well studied in this species, we know much less about how the male and female genitalia interact during mating. This is partly due to the fact that genital interactions occur primarily inside the female, and so are difficult to observe. In this study, we use X-ray micro-CT scanning to examine the proximate mechanisms of traumatic mating in C. maculatus in unprecedented detail. We show that this technique can be used to identify female tissue damage before the melanization of wound sites. We visualize the positioning of the male intromittent organ inside the female copulatory tract during mating, and show how this relates to tract wounding in three dimensions. By scanning pairs flash-frozen at different times during mating, we show that significant tract wounding occurs before the onset of female kicking. There is thus some degree of temporal separation between the onset of wounding and the onset of kicking, which supports recent suggestions that kicking is not an effective female counter-adaptation to reduce copulatory wounding in this species. We also present evidence that the sharp teeth protruding from the female tract wall are able to pierce the spermatophore as it is deposited, and may thus function to aid sperm release.

Dougherty_Simmons_all_data.xlsx（10.40 KB）：所有扫描交配配对的交配创伤程度相关数据。

Video S1.mpg（86.60 MB）：该三维体积渲染影像展示交配早期阶段，雄性阳茎（aedeagus）部分外翻伸入雌性体内的场景（交配60秒后冻存的交配配对，未展示雌性个体）。影像色彩代表组织的相对X射线衰减值（亮度），红色对应最高密度，蓝色对应最低密度。

Video S2.mpg（47.67 MB）：该三维体积渲染影像展示交配早期阶段，雄性阳茎（aedeagus）完全外翻伸入雌性体内的场景（交配60秒后冻存的交配配对，未展示雌性个体）。影像色彩代表组织的相对X射线衰减值（亮度），红色对应最高密度，蓝色对应最低密度。

Video S3.mpg（72.61 MB）：该三维体积渲染影像从侧面视角展示交配早期阶段，雄性阳茎（着色）与雌性交配道（灰度）的相互作用（交配60秒后冻存的交配配对）。色彩分别代表两类组织的相对X射线衰减值（亮度）：雄性结构以红/白色代表最高密度、蓝/深灰色代表最低密度，雌性结构同理。

在四纹豆象（Callosobruchus maculatus）中，雄性插入器官（intromittent organ）表面覆盖有尖锐棘刺，交配过程中会刺穿雌性交配道管壁。尽管该物种中创伤性交配对适合度的影响已得到充分研究，但我们对交配过程中雌雄生殖器的相互作用机制仍知之甚少。这在一定程度上源于生殖器相互作用主要发生在雌性体内，难以直接观测。本研究采用X射线显微计算机断层扫描（X-ray micro-CT）技术，以空前的细节解析了四纹豆象创伤性交配的近因机制。我们证实该技术可用于识别伤口位点黑化前的雌性组织损伤。我们可视化了交配过程中雄性插入器官在雌性交配道内的定位情况，并阐明了其与三维视角下交配道损伤的关联。通过对交配不同时间点快速冻存的交配配对进行扫描，我们发现交配道的显著损伤发生在雌性踢击行为启动之前。由此可见，损伤启动与踢击行为启动之间存在一定的时间间隔，这支持了近期提出的观点：雌性踢击并非有效对抗该物种交配创伤的反适应策略。我们还提供证据表明，雌性交配道壁上突出的尖锐齿状结构可在精荚（spermatophore）沉积时将其刺穿，从而可能辅助精子释放。