The Genome of the Wasp Anastatus disparis Reveals Energy Metabolism Adaptations for Extreme Aggression.

Extremely aggressive behavior is rare in most species, as contestants can be severely injured or killed. Such high level of aggression can evolve when critical resources are limited, as the benefits of winning outweigh the potential costs of conflict. Currently, studies of extreme aggression are mainly from the perspectives of behavioral ecology and evolutionary biology, displaying distinct results from common nonextreme aggression. Here, we provide a high-quality genome of the generalist endoparasitoid Anastatus disparis, the males of which exhibit extreme mate-competition aggression, to shed light on possible genomic adaptations for extreme aggressive behavior. We combined Nanopore PromethION sequencing with Hi-C technology to assemble a high-quality chromosome-level genome of A. disparis. The size of the genome of this species (939.58 Mb) is larger than that of most hymenopterans (ranging from 180 Mb to 340 Mb) due to the expansion of repeated sequences (612.90 Mb, 65.23% of the whole genome). With the aid of RNA sequencing, 19,246 protein-coding genes were identified, and a great expansion of genes involved in detoxification was detected, which could represent an adaptation of this species to exploit a diverse range of known hosts. The integrated multiomics analysis highlighted genes involved in energy metabolism (especially from lipids) and antibacterial activity, both of which are possibly major aspects of adaptation for extreme aggression in A. disparis. Our study provides insight into molecular and evolutionary studies of extreme aggression in A. disparis and provides a valuable genomic resource for further research into the molecular basis of trait evolution in Hymenoptera.