Dung beetles rolling to be cool

Researchers have found dung beetles use their dung balls to cool off in the heat. (Supplied by Wits)

Researchers have found dung beetles use their dung balls to cool off in the heat. (Supplied by Wits)

The roads of the Kruger National Park are littered with massive heaps of elephant dung. For the excited tourist these hold the promise of one of the lumbering giants around the next bend. Fingers hover over camera buttons and most miss the little black dung beetles scuttling off with huge lumps of dung.

We know that they roll up their ball of dung – some 50 times heavier than themselves – to get food away from competitors. But the work is hard, especially when temperatures are scorching and the sand burns. 

To get a bit of relief, researchers have found that the dung beetles climb on top of their ball to cool down. 

Professor Marcus Byrne, from Wits University, said that this only happened around midday, and only when the beetles were crossing hot ground.  

“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,” he said. 

To see if this behaviour was to cool their legs down, the research team applied silicone boots on the beetles front legs. Dr Jochen Smolka, from Lund University, said these cooled their feet down, and as a result the beetles rarely climbed onto the dung. 

While on top of the dung balls, the beetles also spread regurgitated liquid onto their legs and head to cool down a bit more. They do not do this at any other time of the day. 

The beetles have to resort to this behaviour because they are cold blooded – so they need to resort to different techniques to regulate their temperature, said Smolka. 

“Evolution has an astonishing ability to make use of existing structures for new purposes – in this case using a food resource for thermoregulation,” he said. 

 
Sipho Kings

Sipho Kings

Sipho Kings is the person the Mail & Guardian sends to places when people’s environment is collapsing. This leads him from mine dumps to sewage flowing down streets – a hazardous task for his trusty pair of work shoes. Having followed his development-minded parents around Southern Africa his first port of call for reporting on the environment is people on the ground. When things go wrong – when harvests collapse and water dries up – they have limited resources to adapt, which people can never let politicians forget. For the rest of the time he tries to avoid the boggling extremes of corporations and environmental organisations, and rather looks for that fabled 'truth' thing. For Christmas he wants a global agreement where humanity accepts that sustainable development is the way forward. And maybe for all the vested interest to stop being so extreme. And world peace. And a sturdier pair of shoes. Read more from Sipho Kings

Comments

blog comments powered by Disqus

Client Media Releases

Medscheme honoured for service excellence
Do engineers make good project managers?
Hisense SA celebrates Mandela Day at local day care
Hurricane Electric expands into Africa
Frost & Sullivan recognises MiX Telematics for award
MTN appoints new chief HR officer