Galloping Dung Beetles Grab Poo and Store it in a Nest
Posted on November 3, 2013
A South African dung beetle species, Pachysoma Endrodyi, is unique both for its galloping gait and for the way it collects dung. You can see a video of the beetle galloping below. This species of Pachysoma grabs small pieces of dung at a time and carries it back to a nest where it is stored. It does not roll up dung into a ball like other dung beetles.
Professor Marcus Byrne of Wits University says in a release, "This species of Pachysoma grabs bits of poo and gallops forward with it. That is really odd. Most insects walk with a tripod gait. They plant three legs in a triangle, while swinging the other three legs forward. It's an incredibly stable way of walking because you've always got three legs on the ground. For an insect to abandon the tripod gait and use its legs together in pairs like a galloping horse is really radical. The big question is: why are they doing it?"
Byrne and colleagues from Lund University in Sweden believe the beetle may be counting its steps like some ant species are known to do.
Byrne says, "For most dung beetles, it's always a one way trip - grab the poo, run away and never go back. The very marked pacing of Pachysoma's gallop might be giving it a better signal in terms of estimating the return distance from the food to its nest. When it gallops, it slips less in the soft sand. Bees use optic flow as a measure of how fast and how far they've flown. Dung beetles have two eyes on each side of their head, one on top and one on the bottom, looking at the sand and we think Pachysoma might be registering optic flow with its bottom eye over the sand."
Take a look: