Thaumarchaeota are predominant in oligotrophic habitats such as deserts and arid soils, but their adaptations to these arid conditions are not well understood. In this study, we assembled 23 Thaumarchaeota genomes from arid and semi‐arid soils collected from the Inner Mongolia Steppe and the Qinghai‐Tibet Plateau. Using a comparative genomics approach, integrated with 614 Thaumarchaeota genomes from public databases, we identi...