Spatial and temporal trends in dung beetle research

Abstract

Dung beetles are one of the most charismatic animal taxa. Their familiarity as ecosystem service providers is clear, but they also play a range of roles in a variety of different ecosystems worldwide. Here, we give an overview of the current state of dung beetle research and the changes in the prevalence of topics in a collated corpus of 4,145 peer-reviewed articles of dung beetle research, spanning from 1930 until 2024. We used a range of text-analysis tools, including topic modelling, to assess how the peer-reviewed literature on dung beetles has changed over this period. Most of the literature is split into three distinct, but related discourses-the agri/biological topics, the ecological topics, and the taxonomic topics. Publications on the 'effect of veterinary chemicals' and 'nesting behaviour' showed the largest drop over time, whereas articles relating to 'ecosystem function' had a meteoric rise from a low presence before the 2000's to being the most prevelant topic of dung beetle research in the last two decades. Research into dung beetles is global, but is dominated by Europe and North America. However, the research from South America, Africa, and Australia ranges wider in topics. Research in temperate and tropical mixed forests, as well as grasslands, savanna and shrublands dominated the corpus, as would be expected from a group of species directly associated with large mammals. Our assessment of dung beetle research comes when ecosystem service provision is becoming more important and more dominant in the literature globally. This review therefore should be of direct interest to dung beetle researchers, as well as researchers working in agricultural, ecological, and taxonomic arenas globally. Research worldwide and across agri/biological, ecological, and taxonomic discourses is imperative for a continued understanding of how dung beetles and their ecosystem services are modified across rapidly changing natural and agricultural landscapes.

Keywords: Aphodiinae; Corpus; Dung beetle; Ecosystem services; Geotrupinae; Scarabaeinae; Subject topic modelling.

Figure 1. Dendrogram showing relationships between the 20 Dung beetle topics generated.

The six clusters are represented by different colours. Solid line represent specific clusters. Dotted line represents where branches between clusters meet.

Figure 2. Representation of how each topic is distributed within the corpus.

Topics in the bottom right corner are comparatively distributed evenly through the corpus, whereas topics in the top left corner are heavily weighted towards one topic.

Figure 3. (A) Number of dung beetles articles published per year and (B) number of article published overall from each location mentioned in the manuscript.

Figure 4. Change in the prevalence of topics in the dung beetle literature corpus from 1930–2021.

Figure 5. Bumpplot showing the relative change in the publication of topics across each decade from 1930 to 2020.

Figure 6. Location of dung beetle publications across each of the 20 topics.

Country colour indicative of topic prevalence.

Figure 7. Biome plot indicating the number of mentions of each biome across the 20 topics.

Topics grouped into their six clusters (as per Fig. 1). Cell colour indicative of topic prevalence.

Figure 8. Taxonomic mentions across all topics: (A) Genus level, (B) Family level, (C) Order level.

Bar colour indicative of topic prevalence.

Figure 9. Heatmap of family mentions across the 20 topics.

Topics groups into Clusters as Per Fig. 1. Cell colour indicative of topic prevalence.