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.

Bee monitoring, or widespread efforts to document bee community biodiversity, can involve data collection using lethal (specimen collections) or non-lethal methods (observations, photographs). Additionally, data can be collected by professional scientists or by volunteer participants from the general public. Collection-based methods presumably produce more reliable data with fewer biases against certain taxa, while photography-based approaches, such as data collected from public natural history platforms like iNaturalist, can involve more people and cover a broader geographic area. Few efforts have been made to quantify the pros and cons of these different approaches. We established a community science monitoring program to assess bee biodiversity across the state of Pennsylvania (USA) using specimen collections with nets, blue vane traps, and bowl traps. We recruited 26 participants, mostly Master Gardeners, from across the state to sample bees after receiving extensive training on bee monitoring topics and methods. The specimens they collected were identified to species, stored in museum collections, and the data added to public databases. Then, we compared the results from our collections to research-grade observations from iNaturalist during the same time period (2021 and 2022). At state and county levels, we found collections data documented over twice as much biodiversity and novel baseline natural history data (state and county records) than data from iNaturalist. iNaturalist data showed strong biases toward large-bodied and non-native species. This study demonstrates the value of highly trained community scientists for collections-based research that aims to document patterns of bee biodiversity over space and time.

Insect eggs, once oviposited, defend against abiotic and biotic factors using thickness, secretions, or other defenses. The eggs of most insect species are attacked by parasitoid wasps, which are often their most significant mortality factors. The present study is the first investigation of microfilaments as defense from parasitoids. Specifically, the effect of the corn leafhopper Dalbulus maidis DeLong (Hemiptera: Cicadellidae) egg microfilaments against parasitism by Anagrus virlaiTriapitsyn (Hymenoptera: Mymaridae) and Paracentrobia subflava (Girault) (Hymenoptera:Trichogrammatidae) was evaluated. Field and laboratory experiments were conducted to evaluate several biological traits related to parasitism in D. maidis eggs with and without microfilaments. An initial field experiment found no difference in parasitism by A. virlai and P. subflava of eggs with vs. without microfilaments after 5 days of exposure of healthy D. maidis eggs to parasitism. A second field experiment then looked at exposure for 1 day, and this treatment found greater parasitism of healthy D. maidis eggs by each parasitoid species in eggs without microfilaments vs. in eggs with microfilaments. Laboratory experiments conducted separately for A. virlai and P. subflava parasitism after 1 day of exposure to healthy D. maidis eggs confirmed a higher percentage of parasitoid emergence in the eggs without microfilaments (both young and mature eggs) vs. mature eggs with microfilaments. These results suggest that eggs without microfilaments are more parasitized than eggs with microfilaments during a 1-day exposure, but that this difference disappears as egg microfilaments regrow over a 5-day period.

Graphical Abstract