Metagenomics reveals that dung beetles (Coleoptera: Scarabaeinae) broadly feed on reptile dung. Did they also feed on that of dinosaurs?

Abstract

The origin of the dung-feeding habits in dung beetles (Coleoptera: Scarabaeinae) is debatable. According to traditional views, the evolution of dung beetles (Coleoptera: Scarabaeinae) and their feeding habits are largely attributed to mammal dung. In this paper, we challenge this view and provide evidence that many dung beetle communities are actually attracted to the dung of reptiles and birds (= Sauropsida). In turn, this indicates that sauropsid dung may have played a crucial evolutionary role that was previously underestimated. We argue that it is physiologically realistic to consider that coprophagy in dung beetles could have evolved during the Cretaceous in response to the dung produced by dinosaurs. Furthermore, we demonstrate that sauropsid dung may be one of the major factors driving the emergence of insular dung beetle communities across the globe. We support our findings with amplicon-metagenomic analyses, field observations, and meta-analysis of the published literature.

Amplicon metagenomics of dung beetles (Coleoptera, Scarabaeidae, Scarabaeinae) as a proxy for lemur (Primates, Lemuroidea) studies in Madagascar

“…Recently, attempts have been made to use DNA metabarcoding with High-Throughput, or Next-Generation, sequencing (NGS) to identify taxa in material samples, such as plant species in herbivore dung, prey species in the gut contents of predators, or soil samples ( Taberlet et al 2012 ; Kocher et al 2017 ). Animal manure includes not only the DNA of the food, but also the DNA of the animal producing the manure ( Shehzad et al 2012 ; De Barba et al 2014 ; Lopes et al 2023 ). Three studies have been published using NGS to identify mammalian food sources for coprophagous beetles.…”

Dung beetle (Coleoptera: Scarabaeinae) attraction to woodcreeper (Aves: Dendrocolaptidae) dropping in the central Amazon

“…Nonetheless, bird droppings seem to be a part, though not frequent, of the usual diet of dung beetles. For example, on the island of Mauritius, Neosysiphus Müller, 1942 beetles are usually attracted to fowl droppings (Vinson 1951;Lopes et al 2023), while in France a few species belonging to genera such as Onthophagus Latreille, 1802 and Copris Geoffroy, 1762 are commonly found in the droppings of little bustards, Tetrax tetrax Linnaeus, 1758 (Perrin et al 2019). New Zealand currently lacks a native land-mammal fauna (except for bats), but formerly harbored a rich community of large birds (e.g., the kakapo and the extinct moas), which may have acted as the main food providers for dung beetles (Jones et al 2012;Stavert et al 2014).…”

“…New Zealand currently lacks a native land-mammal fauna (except for bats), but formerly harbored a rich community of large birds (e.g., the kakapo and the extinct moas), which may have acted as the main food providers for dung beetles (Jones et al 2012;Stavert et al 2014). The same was perhaps true for Mauritius, where the now extinct giant dodo (Raphus cucullatus, Linnaeus, 1758) may have co-existed with dung beetles (Vinson 1951;Lopes et al 2023). However, to the best of our knowledge, there are almost no published records of dung beetles attracted to bird droppings in South America.…”