Neofunctionalization of an ancient domain allows parasites to avoid intraspecific competition by manipulating host behaviour

Intraspecific competition is a major force in mediating population dynamics. This study uses the *Drosophila* parasite *Leptopilina boulardi* to investigate superparasitism and supraparasitism avoidance. Researchers found that this solitary endoparasitic wasp manipulates host escape behavior to avoid superparasitism. Multi-omics and in vivo functional studies identified RhoGAP domain-containing genes mediating this manipulation by inducing reactive oxygen species in the host central nervous system. Neofunctionalization and specialization of the RhoGAP domain in avoiding superparasitism are shown to have an ancestral origin before the divergence of specialist and generalist *Leptopilina* species. The study concludes that supraparasitism avoidance is adaptive for the parasite, adding to the understanding of host behavior manipulation evolution.

Jiani Chen, Gangqi Fang, Lan Pang, Yifeng Sheng, Qichao Zhang, Yuenan Zhou, Sicong Zhou, Yueqi Liu, Zhiguo Liu, Yixiang Zhang, Guiyun Li, Min Shi, Xuexin Chen, Shuai Zhan, Jianhua Huang