What are dung beetles?

 Well, beetles that feed on dung. But while this is largely true, the definition of dung beetle is actually more complicated, being a mixture of an ecological trait (coprophagy) and a taxonomic classification (belonging to the scarabs). So dung beetles are those species of the large superfamily of scarab beetles (Scarabaeoidea) that feed on manure or belong to a taxonomic group that contains mainly dung-feeders. Dung feeding (coprophagy) has evolved several times within the scarabs, with the major groups being the Geotrupidae (dor beetles; ~150 species), the Aphodiinae (dung dwellers; ~3,500 species, Figure 1), and the Scarabaeinae (the dung beetles proper; ~7,000 species, Figure 2).

Figure 1. Beetle (family: Passalidae) with three different species of mites (indicated by A, B, C) attached. (See Ermilov & Frolov 2019b.)

Mites may be found worldwide in almost any habitat imagined, from arctic tundra to hot deserts, from marine habitats to forests. Collectively, they also eat an extraordinarily wide variety of food.  However, when the habitat becomes too crowded, or the specific food source has run out, they have to disperse to the next optimal space. Sometimes it is as easy as walking to the next spot, but sometimes the next food source is quite a distance away, and being so small and wingless, walking is just impractical.

The researchers at the National Museum go on regular field expeditions to collect animals, plants, and fossils for research and to build the collections. Such a field expedition is quite complicated to organise. Here is an example of a field expedition of an approved project to explain the process.

The 11 orders of Arachnids

The class Arachnida contains some of the most fascinating and enigmatic arthropods on earth, many of which are completely unknown to the general public. To remedy this, this article provides information covering each of the 11 different groups or orders of arachnids.