We think this is because dung beetles are not very fussy about what kind of dung they eat. While many beetles have a preferred food type, few specialize only on a single dung type. So, if one mammal species is lost from an area, most dung beetles can simply switch to the dung of another mammal species for their next meal Figure 3B.
We discovered that some dung beetles even feed on python dung! However, although networks were resilient in moderately disturbed habitats, we found that in heavily disturbed sites, such as oil palm plantations and small isolated forest patches, the networks did become simplified, with fewer dung beetle species and fewer interactions between beetles and mammals [ 2 ] Figure 3C.
Using traps baited with dung to catch beetles only tells us if the beetles are attracted to the dung, but not if those beetles actually feed on that dung type. We could only bait traps with dung from mammals that we could easily find, like animals kept in zoos. Luckily, new laboratory methods are allowing us to know exactly which mammal dung the beetles have been feeding on. So, in our current work, we are dissecting the guts of beetles to analyze the genetic material of the beetle gut contents.
This method allows us to identify which mammal dung the beetles were feeding on before they were captured. We hope that this will allow us to document more complete networks, including rare or difficult-to-study mammal species, and the interactions between mammals and dung beetles that live in the forest canopy—yes, there are canopy dung beetles too!
Dung beetles are important members of agricultural ecosystems , and many researchers have explored how dung beetles help support the production of food [ 3 ]. For example, flies that bite and disturb cows and other farm animals, lay their eggs in dung and the immature fly larvae then feed on dung when they hatch.
Dung beetles help to keep farm animals like sheep, cows, and horses healthier by burying farm animal dung, so that it is not available for the flies to breed in.
Dung beetles also help to reduce parasite infections of farm animals. Parasitic nematodes , which are tiny worms, are eaten by animals grazing in the pastures. The nematodes then multiply in the animals and their eggs are excreted in the dung. When the eggs hatch, the larvae migrate to the grass and are ingested by grazing animals, like cows or sheep, which quickly increases the infection rates.
When dung beetles tunnel through dung, they cause it to dry out. This kills the eggs, and reduces the numbers of parasitic nematodes in the pasture, which leads to fewer infected animals. This tunneling action also helps with the recycling and mixing of the soil, which aids the movement of nutrients through the soil so they can be available by plants. Because dung beetles are relatively small and often secretive, many farmers may not even recognize that dung beetles live on their farms.
Dung beetles are sensitive to how pastures are managed. Adult female beetles mate and lay eggs. The eggs hatch into a larval stage that is wingless. The larva feed and grow, and eventually change into a pupal stage. The pupa does not move or feed.
Eventually the pupa transforms into an adult beetle. Female beetles usually lay dozens or hundreds of eggs. Reproduction is often timed to match the time of most available food. Adult beetles mate, and the female lays eggs on or very near a food source for her larvae. Some beetles collect a supply of food for their larvae, and lay the egg in the ball of food. Some scavenger beetles even feed their babies. Most beetle species complete their lives in a single year. Some, especially larger ones, live for more than a year, hatching in summer, a few months to a year or more as a larva and pupa, and then emerging to reproduce as an adult.
Most beetles are active at night, but some are active in daylight especially if they have chemical defense. Often they time their growth and reproduction so all the adults emerge at once, and for a short time you can find lots of a particular species. Most beetles communicate with other beetles with chemicals. Males often locate females by their scent.
Beetles usually can't see very well. Some beetle make sounds, usually scraping their mouthparts together or rubbing their legs on their bodies. Some beetles that live in dead wood drum and make vibrations. They glow in the dark to communicate. Beetles eat all kinds of food. The tunnellers build elaborate underground chambers close to or beneath the dung pats using the fibrous parts from the dung. The dwellers live within the dung and breed. This stratified living helps reduce competition for the precious resource that is the dung, at least to some extent.
However, there are as many opportunists in this world of beetles as there are among humans. Some dung beetles are kleptoparasites, stealing dung balls at the first chance. The French naturalist Jean Henri Fabre has documented such behaviour extensively. In one case, according to him, the male that had helped a female roll the dung and had been expected to guard it tried stealing and running away with it. The female was busy digging a burrow to bury it. For the beetles, dung is an ephemeral resource.
They have to compete with members of their own community and with others, too, such as dung-eating flies. Some dung beetles prefer the coarse, fibre-filled dung of non-ruminants like primates, horses, dogs, swines and even humans — while others prefer the fluid-filled, fine variety of ruminants such as goats, sheep, camels, buffaloes and deer.
There are even others that search specifically for the smelly excreta of omnivores. For specialist feeders like the elephant dung beetle Heliocropis dominus , which relies exclusively on elephant sometimes gaur dung, the competition is tough.
According to A. V Kumar, a beetles specialist from the University of Agricultural Sciences, Bengaluru, there are at least a hundred other species of dung beetles that seek faecal matter of the same origin.
And the decreasing population of elephants in the wild does not bode well. Powderpost beetles lay their eggs in cracks of wood. They are found in hardwood floors, timbers and crates, antiques and other things made of hard wood.
Powderpost beetles dig holes in wood. They can kill or damage trees and things made from wood like furniture. There are even documented cases that Powderpost beetles have destroyed houses! Find more educational materials for use in your classroom, including a profile on Powderpost beetles , at the official NPMA website. These beetles have extremely flat bodies. This body shape allows them to crawl into packaged foods to eat, live and reproduce. It only takes them about weeks to grow from baby to adult and an adult Merchant Grain beetle can live up to 3 years.
Merchant Grain beetles can be found all over the world and can live in cooler climates. Despite their name, these insects do not ear grain! Once confused with a kind of beetle that does eat grain, the Merchant beetle was scientifically re-categorized, but the name stuck.
These beetles get their name because they were commonly found on merchant ships, hiding in organic cargo. They are drawn to foods high in fat, such as cereals, cake mixes, macaroni, cookies and chocolate.
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