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Traumatic insemination (TI) is a rare reproductive behaviour characterized by the transfer of sperm to the female via puncture wounds inflicted across her body wall. Here, we challenge the claim made by Kamimura (Kamimura 2007 Biol. Lett. 3 , 401–404. ( doi:10.1098/rsbl.2007.0192 )) that males of species of the Drosophila bipectinata complex use a pair of claw-like processes (claws) to traumatically inseminate females: the claws are purported to puncture the female body wall and genital tract, and to inject sperm through the wounds into the lumen of her genital tract, bypassing the vaginal opening. This supposed case of TI is widely cited and featured in prominent subject reviews. We examined high-resolution scanning electron micrographs of the claws and failed to discover any obvious ‘groove’ for sperm transport. We demonstrated that sperm occurred in the female reproductive tract as a single-integrated unit, inconsistent with the claim that sperm are injected via paired processes. Laser ablation of the sharp terminal ends of the claws failed to inhibit insemination. We showed that the aedeagus in the complex delivers sperm through the vaginal opening, as in other Drosophila . The results refute the claim of TI in the Drosophila bipectinata species complex.
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This content will become publicly available on February 15, 2026
Traumatic injury leads to ovarian cell death and reproductive disturbances in Drosophila melanogaster
ABSTRACT Traumatic injury (TI), or global blunt force trauma, can arise from many sources such as car crashes, sports and intimate partner violence. Effects from these injuries impact the whole organism and can lead to many different pathologies, such as inflammation, neurodegeneration, gut dysbiosis, and female reproductive detriments. Drosophila melanogaster has recently emerged as a powerful model to study traumatic injuries due to their high conservation of physiological effects post-trauma and the genetic toolset that they leverage. Previously, we reported female-specific reproductive deficits post mild TI in Drosophila. Here we investigate the effects of more severe trauma on females and found an increased retention of mature eggs and decrease in egg laying. Additionally, severe trauma led to an increase of midstage egg chamber death and formation of melanization, a known marker of immune activation. These studies provide a valuable invertebrate model to understand disturbances to female reproduction post-trauma.
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- Award ID(s):
- 2150124
- PAR ID:
- 10574861
- Publisher / Repository:
- The Company of Biologists
- Date Published:
- Journal Name:
- Biology Open
- Volume:
- 14
- Issue:
- 2
- ISSN:
- 2046-6390
- Subject(s) / Keyword(s):
- Traumatic brain injury Drosophila
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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