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Heritable symbionts display a wide variety of transmission strategies to travel from one insect generation to the next. Parasitoid wasps, one of the most diverse insect groups, maintain several heritable associations with viruses that are beneficial for wasp survival during their development as parasites of other insects. Most of these beneficial viral entities are strictly transmitted through the wasp germline as endogenous viral elements within wasp genomes. However, a beneficial poxvirus inherited by Diachasmimorpha longicaudata wasps, known as Diachasmimorpha longicaudata entomopoxvirus (DlEPV), is not integrated into the wasp genome and therefore may employ different tactics to infect future wasp generations. Here, we demonstrated that transmission of DlEPV is primarily dependent on parasitoid wasps, since viral transmission within fruit fly hosts of the wasps was limited to injection of the virus directly into the larval fly body cavity. Additionally, we uncovered a previously undocumented form of posthatch transmission for a mutualistic virus that entails external acquisition and localization of the virus within the adult wasp venom gland. We showed that this route is extremely effective for vertical and horizontal transmission of the virus within D. longicaudata wasps. Furthermore, the beneficial phenotype provided by DlEPV during parasitism was also transmitted with perfect efficiency, indicating an effective mode of symbiont spread to the advantage of infected wasps. These results provide insight into the transmission of beneficial viruses among insects and indicate that viruses can share features with cellular microbes during their evolutionary transitions into symbionts.
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Fine-tuned thin-plate spline motion model for manipulating social information in paper-wasp colonies
Several species of Polistes paper wasp are well known for their social hierarchies and the ability for individual wasps to modulate their social behaviors based on recognizable facial features of other wasps. For example, wasps that observe an aggressive social interaction between two other wasps will later behave differently toward the winner and loser of that interaction. Being able to alter the physical appearance of wasps~(e.g., with paint) has allowed for testing hypothetical roles of individual recognition in hierarchy formation, which is how researchers know that wasps are attending to faces specifically. However, these physical methods are limited in their scope. Social insects who respond to visual stimuli from other insects have been shown to give the same responses to playbacks of video recordings of those stimuli, which suggests that there may be a role for generative methods in social-insect research. Being able to computationally change the faces of individual wasps in a video recording of wasp social interactions would greatly expand the experimental toolbox of the behavioral researcher. Toward this end, we evaluate the use of an existing annotation-free model for image animation by motion transfer, the thin-plate spline motion model, for creating realistic videos that depict the face of a paper wasp performing behaviors recorded by another. Not needing to pre-define important landmarks is a strength of this method for this application space, but we find that "deep faking wasps" poses unique and non-trivial problems that still need to be solved before off-the-shelf motion transfer models can be used in the insect behavioral laboratory.
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- Award ID(s):
- 2319438
- PAR ID:
- 10547703
- Editor(s):
- Waldmann, Urs; Wu, Shangzhe; Yang, Gengshan; Zamansky, Anna
- Publisher / Repository:
- 2024 Computer Vision for Animal Behavior Tracking and Modeling (CV4Animals at CVPR 2024)
- Date Published:
- Format(s):
- Medium: X
- Location:
- Seattle, WA
- Sponsoring Org:
- National Science Foundation
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