Research trends and knowledge gaps in the ecology of dung beetles (Coleoptera: Scarabaeidae) in savannas

Savannas are recognized as one of the world's most biodiverse ecosystems. However, these environments have the highest rates of habitat loss due to land use and climate-induced alterations in fire regimes. The combination of these threats, along with knowledge gaps in biodiversity, represents formidable challenges to conservation efforts in these regions. Dung beetles, vital for comprehending the impact of land use on savannas, have yet to undergo comprehensive study. To address this gap, we conducted a systematic review of the current state of knowledge regarding dung beetles distributed in savannas within Neotropical, Afrotropical, and Australasia zoogeographic regions. We describe the encompassing geographical distribution, research topics, studied habitats, and key metrics assessed in existing studies. Our results reveal a pronounced focus on Neotropical savannas highlighting a substantial deficit in dung beetle ecology knowledge within Afro-tropical and Australasian savannas. Most articles focused on savanna grasslands, woodlands, and human-introduced habitats such as pastures. The predominant articles focused on community patterns, habitat replacement, and degradation. Noteworthy metrics included abundance, richness, and species composition. Diversity indexes and functional diversity were also relatively well-explored metrics. However, across all zoogeographic regions, aspects of dung beetle behavior, reproductive biology, and physiology remain inadequately explored. In conclusion, urgent research efforts are imperative, emphasizing the need for comprehensive metrics, including biomass, morphometrics, and ecological functions of dung beetles, to advance our understanding of their significance and roles within savannas.