The Brown Beetle
Kelly’s Field Notes
Common Name: Dung Beetles
Order: Coleoptera “sheath wings” named for their armor like forewings
Family: Geotrupidae (all species use dung, “earth-boring dung beetles”), Scarabaeidae (some species use dung) (Subfamily: Scarabaeinae “true dung beetles”, Subfamily Aphodiinae “small dung beetles”)
Genus: There are over 240 genera of dung beetles worldwide!
Species of Note Near You (There are around 7,000 species of dung beetle!):
Carolina copris (Dichotomius carolinus) - found primarily in the eastern U.S. to the Mississippi River, and throughout Central America into parts of South America, but spotty.
Common dung beetle (Canthum imitator) - found in Texas, the southwestern U.S., and Mexico.
Humpback dung beetle (Deltochilum gibbosum) - found in the southeastern U.S.
Small black-and-brown dung beetle (Onthophagus nuchicornis) - found primarily in the northwest U.S. but also into northern Europe as well.
Elephant dung beetle (Heliocopris bucephalus) - found throughout India and southeast Asia.
Diurnal Copper Dung Beetle (Kheper nigroaeneus) - found throughout south eastern Africa.
Description:
Dung beetles vary greatly in size, from the tiny (Aphodius pseudolividus) at 3 mm (1/8th of an inch) to the big boys and gals of 32 mm (1.25 in) like the Carolina copris (Dichotomius carolinus), both found in North America (A. pseudolividus has a near worldwide distribution), to the largest dung beetle the elephant dung beetle (Heliocopris bucephalus) that can be 55 m (2.17 in). Dung beetles are generally dark brown to black in color, though some are lighter and spotted, most are shiny. Some species, such as the Rainbow scarab (Phanaeus vindex), are vibrantly colored in metallic green or other colors. Some males have impressive horns for battling each other.
They are found worldwide on every continent except Antarctica in a variety of habitats from hot dry desert to lush forests.
Life Cycle:
Dung beetles have a complete metamorphosis, egg, larva, pupa, adult. Their entire life cycle revolves around dung! Most dung beetles will spend 95% of their lives either in dung or in a nest below a dung pat. After males and females pair up they create a nest environment, which differs depending on the species. There are rollers, tunnelers, and dwellers.
Dwellers (Endocoprids) lay their eggs directly within a dung pat. This provides the larvae with an abundance of food, though it does leave them susceptible to predators. Tunnelers (Paracoprids) create tunnels below the dung pat to lay their eggs in, sometimes many branching tunnels and sometimes a single tunnel. They even have specialized limbs (fossorial legs) made for digging! When the larvae hatch they make their way up the tunnel to the dung. Rollers (Telecoprids) roll their eggs up into dung balls then stash them in tunnels they’ve dug out, away from the dung pats to protect them from predators. Dung beetles either find the dung via scent or hitch a ride on the dung producer of their choice. They will also attempt to steal dung from each other. An outdated thought was that they would help each other get over obstacles, but really they were waiting to steal each other’s dung.
One female will usually lay between 10-80 eggs in her lifetime, which take only 1 to 2 days to hatch. The larvae spend their days eating until they are about 1 to 4 weeks old, then it is time to pupate. Depending on the species, a dung beetle pupa can remain in that stage for two weeks up to several months. Their entire life cycle can take up to 2 years. Adults can eat mushrooms and rotting vegetation but prefer liquified material and dung.
Distribution:
While species are found throughout the world, many have been introduced to improve agriculture. For example, there are 500 native species in Australia but an additional 29 have been successfully introduced from Hawaii, Africa, and Southern Europe. The Aussie’s native species are not adapted to consume and use wet cattle dung (they eat dry marsupial dung) so non-native species were introduced to give their agriculture a hand. Similar introductions have happened in New Zealand and parts of North and South America.
Super Powers:
Flight - dung beetles can fly for short distances
Celestial Navigation - the nocturnal African dung beetle, Scarabaeus satyrus, is the only known animal other than humans to navigate and orient itself using the Milky Way. This theory has been proposed in vertebrates and spiders but not yet proven. They are also the first known animal to navigate by polarization patterns in moonlight.
Strength - the horned dung beetle (Onthophagus taurus) can pull up to 1,141 times its own body weight! This is the human equivalent of lifting two fully-loaded 18-wheeler trucks.
Dung beetles in Culture:
Dung beetles are an important part of livestock! They eat dung which lessens the number of flies and nematodes which carry disease. Dung beetles save the U.S. cattle industry $380 million a year through burying dung.
Dung beetles improve nutrient cycling in the soil by tunneling and burying dung. They also reduce soil compaction, increase aeration, and reduce runoff after heavy rain events.
In South Africa dung beetles have helped shift old coal mines back to natural spaces, encouraging plant growth.
Dung beetles are proclaimed to be a cure for several diseases according to traditional Chinese medicine practices (please do not take any supplements before speaking with a doctor).
The Mediterranean dung beetle (Bubas bison) has been used in conjunction with biochar (charcoal mixed with molasses fed to cows) to reduce greenhouse gas emissions by burying the biochar infused dung. This also eliminates the use of machines to perform the same task.
The ancient Egyptians venerated scarab beetles as symbols of renewal. The sacred scarab (Scarabaeus sacer), a species of dung beetles, was one of many. The image of beetles in Egyptian hieroglyphics translates to "to come into being", "to become" or "to transform."
In Aristophanes’s play Peace the hero’s steed is a giant dung beetle.
Hans Christian Anderson has a fable called “The Dung Beetle” about a dung beetle living in a king’s horse stable.
Book Recommendations:
Byrne, Marcus. Dance of the Dung Beetles: Their Role in Our Changing World. Wits University Press, 2019.
Evans, Arthur V. Beetles of Eastern North America. Princeton University Press, 2014.
Evans, Arthur V. and C. L. Bellamy. An Inordinate Fondness for Beetles. University of California Press, 2000.
Walters, Charles. Dung Beetles & a Cowman's Profits. Acres U.S.A, 2015.
Kids Book Recommendations:
Bardoe, Cheryl and A. Marks. Behold the Beautiful Dung Beetle. Charlesbridge, 2018.
Davey, Owen. Bonkers About Beetles. Flying Eye Books. 2018.
Pett, Mark. I Eat Poop.: A Dung Beetle Story. Roaring Brook Press, 2021.
Documentary Recommendations:
Basically anything with David Attenborough, but specifically episode 5 of the BBC's Africa about the Sahara desert
References:
Amos, Jonathan. “Dung Beetles Guided by Milky Way.” BBC News, 22 Jan. 2013, www.bbc.com/news/science-environment-21150721. Accessed 21 July 2023.
Badenhorst, Jessica, et al. "Dung beetle activity improves herbaceous plant growth and soil properties on confinements simulating reclaimed mined land in South Africa." Applied Soil Ecology 132 (2018): 53-59.
Dacke, Marie, et al. "Dung beetles use the Milky Way for orientation." Current biology 23.4 (2013): 298-300.
Daly, Jon. “Dung Beetles, Poo and Charcoal Help This Farmer Tackle Effects of Climate Change.” ABC News, 18 Oct. 2019, www.abc.net.au/news/rural/2019-10-18/wa-farmer-uses-beetles-and-charcoal-to-combat-climate-change/11613846.
“Dung Beetles | Science Literacy and Outreach | Nebraska.” Entomology.unl.edu, entomology.unl.edu/scilit/dung-beetles. Accessed 21 July 2023.
“Dung Beetles and Their Benefits to Farmers.” Burnett Mary Regional Group, 22 Mar. 2023, bmrg.org.au/dung-beetles-and-their-benefits-to-farmers/. Accessed 21 July 2023.
Losey, John E., and Mace Vaughan. "The economic value of ecological services provided by insects." Bioscience 56.4 (2006): 311-323.
Martínez, Imelda, et al. "New data on the distribution and reproductive biology of Canthon imitator Brown 1946 (Coleoptera: Scarabaeidae: Scarabaeinae)." Acta zoológica mexicana 35 (2019).
Schenkman, Lauren. “ScienceShot: World’s Strongest Insect.” Www.science.org, 23 Mar. 2010, www.science.org/content/article/scienceshot-worlds-strongest-insect. Accessed 21 July 2023.
“Species Canthon Imitator.” Bugguide.net, bugguide.net/node/view/87192. Accessed 21 July 2023.
“Species Deltochilum Gibbosum - Humpback Dung Beetle.” Bugguide.net, bugguide.net/node/view/4533. Accessed 21 July 2023.
Wikipedia Contributors. “Dung Beetle.” Wikipedia, Wikimedia Foundation, 30 May 2019, en.wikipedia.org/wiki/Dung_beetle. Accessed 21 July 2023.