Beetles use dung balls to stay cool

Oct 22, 2012
Researchers from South African and Sweden applied silicone boots to the front legs of dung beetles as alternative protection from the heat to prove their theory that dung beetles climb their dung balls to cool down. Credit: Wits University

Dung beetles roll their feasts of dung away to avoid the hoards of other hungry competitors at the dung pile. But now a team of researchers from South Africa and Sweden have discovered that they also use their balls in another, rather clever way. The moist balls keep the beetles cool even as they push a weight up to 50 times heavier than their own bodies across the hot sand.

"The beetles climb on top of their moist balls whenever their front legs and heads overheat," said Prof. Marcus Byrne from Wits University. "We stumbled upon this behaviour by accident while watching for an 'orientation dance' which the beetles perform on top of their balls to work out where they're going. We noticed that they climbed their balls much more often in the heat of the midday sun."

Further experiments showed that this midday phenomenon only held true when the beetles were crossing hot ground. In fact, beetles on hot soil climb their balls seven times as often as those on cooler ground.

To show that it was the beetles' hot legs that made them climb the ball, the researchers applied some cool (as in temperature) boots to their front legs as alternative protection from the heat. "To our great surprise, this actually worked, and beetles with boots on climbed their balls less often," said Dr Jochen Smolka from Lund University, who collaborated on the research.

The discovery marks the first example of an insect using a mobile thermal refuge in this way. It is also a demonstration of the remarkably sophisticated strategies that and other cold-blooded creatures employ to maintain their .

Once on top of a ball at midday, the were often seen "wiping their faces", a preening behavior that the researchers suspect spreads regurgitated liquid onto their legs and head to cool them down further. That's something the insects never do at other times of day.

The findings are yet another reminder of the many creative solutions found in nature. According to Smolka, "Evolution has an astonishing ability to make use of existing structures for new purposes – in this case using a food resource for thermoregulation."

Explore further: Honey bees sting Texas man about 1,000 times

More information: Smolka et al.: "Dung beetles use their dung ball as a mobile thermal refuge," Current Biology.

Related Stories

Dung beetle dance provides crucial navigation cues

Jan 18, 2012

(PhysOrg.com) -- The dung beetle dance, performed as the dung beetle moves away from the dung pile with his precious dung ball, is a mechanism to maintain the desired straight-line departure from the pile, ...

Flapping protective wings increase lift

May 29, 2012

New research from Lund University in Sweden reveals the value of carrying two layers of wings around. The researchers studied dung beetles and the way their protective forewings actually function. These wings do not only ...

Female dung beetles use horns to fight over manure

Mar 04, 2010

(PhysOrg.com) -- Dung beetles are among the few species in which the females are more impressively equipped with armor than males, and a new study explains why: the females fight each other for the best manure ...

Far-flung dung beetles here to 'finish the job'

Jun 06, 2012

Specially chosen for their spring frenzy and voracious appetite for dung, two new species of European dung beetles have arrived in Australia to improve cattle pastures and finish off a job well started through ...

Recommended for you

A tiny new species of frog from Brazil with a heroic name

9 hours ago

The Atlantic Forest is a hotspot of biodiversity and one of the most species richness biome of anurans (frogs, tree-frogs, and toads) in the world. However, current levels of diversity might be still underestimated. ...

User comments : 4

Adjust slider to filter visible comments by rank

Display comments: newest first

baudrunner
not rated yet Oct 22, 2012
Sweatbands and bandanas, perhaps?
ValeriaT
not rated yet Oct 22, 2012
It's nothing new for me. Many people are spending huge money for various sh..ts just to appear cool before their contemporaries...
VendicarD
5 / 5 (1) Oct 23, 2012
Fascinating. Republicans use their dung balls for the same purpose.
88HUX88
not rated yet Oct 23, 2012
btw that's hordes