Weird Animals - the Dung Beetle
There are some insects, like bees, whose praises I have sung. But never this weird beetle who transports and lives in dung.
What would you say if I told you there is an insect that loves dung, lives in dung, eats dung, feeds dung to its offspring and often rolls balls of dung for long distances while standing on its head and moving backward using its hind legs? It's true. I'm not making this up.
Dung, of course, is excrement, manure, feces - any droppings produced by herbivores or grass-eating animals. The Scarab family of beetles (Scarabaeidae) has thousands of species located all over the world. In ancient Egypt, the scarab or dung beetle was an important religious symbol. It seems that Khepri was a scarab god of the sun who rolled the sun across the heavens each morning and buried it each evening. Much like the scarab beetle rolling its ball of dung and then burying it. Scarab amulets became popular and are worn by many people today as a symbol of rebirth.
Most dung beetles make tunnels or burrows in the soil. They shape the fresh dung they find into small round balls and transport it to their tunnels. They may have to roll the dung balls up to 100 meters away. And some of the larger dung beetles are able to move balls of dung up to 50 times their own weight.
Dung Beetles Fighting over Dung
An adult dung beetle ranges in size from 2 to over 50mm in length. Most species are dark brown or black but a few have bright patterns or metallic colors. They are built like a bulldozer with strong legs fitted for digging and a blunt shovel-like beak used for shaping the dung ball. Once they find nice fresh dung, they separate it from the pile and either begin to eat it on the spot, or start rolling it away. These amazing beetles burrow into the dung and build a ball of dung and soil. When they arrive at their designated homestead, they dig a tunnel, roll the dung ball down inside it, and bury it to be eaten when needed.
In late summer the female buries a few special pear-shaped dung balls and lays a creamy white egg in each one. Soon the grub or larva feeds on the dung and grows until the ball is a hollow shell. After the pupa stage, the new adult dung beetle breaks out, usually after a rain, and digs its way to the surface. When it emerges, it fills in the hole and flies away to repeat the cycle.
Warning! This description of their dining habits is not for the squeamish. As mentioned earlier, dung beetles love fresh dung. They shovel the dung into their shovel-shaped mouths, squeeze it and eagerly drink the foul-smelling juices. The solid part of the dung is then squeezed again by their jaws and then swallowed. Why the second squeezing? If there are any eggs that flies have already laid inside the dung, the squeezing action kills them.
In Africa, dung beetles often head for the hot, steaming herbivore patty before it hits the ground. As they are buzzing around, they are attracted by the gas that the animal releases. Useless facts department: each cow on earth emits about 300 liters of methane gas each day. Humans are not as productive
In the U.S., the dung beetle is known as the tumblebug. How did it get its name? Since these beetles roll their dung balls considerable distances over grass and bumpy ground, both the dung ball and the dung beetle take many a tumble.
On The Serengeti plains in Africa, it is estimated that dung beetles roll away and bury up to 75% of the dung produced by animals. If dung beetles did not exist, the patties of dung produced would harden and cover the ground. Grasslands and other plants would not be able to grow. Another benefit they provide is reducing the numbers of insects like flies which use dung in which to reproduce.
Some dung beetles are generalists with no specific dung preferences. Others are specialists who prefer only the dung of the wildebeest, rhino, elephant, etc. There is even a dung beetle in South America who dines only on the feces of large snails - on whom it rides around.
There are two species of dung beetles who are the bad guys. The first is the kleptocoprophage dung beetle that eats and lays its eggs in dung some other hard-working dung beetle has collected, and also eats the dung-ball-owner's eggs. The second is more ferocious. It is a scarab beetle in Peru that has been filmed attacking and dining on millipedes ten times its length. These beetles no longer rolled dung balls. Instead they preferred eating live prey.
Researchers believe that these predator-type beetles evolved from scavenger-type beetles because of the high competition for food. Most dung beetle adults aggressively defend their dung balls from competitors by chasing and butting each other. Revisit the dung beetle dung battle in the video above.
© Copyright BJ Rakow 2010, 2013 Rev. All rights reserved. Author, "Much of What You Know about Job Search Just Ain't So." A serious book about job search strategies written in a light-hearted fashion.