Most dung beetles gather "fresh" poop and pack it into one wet ball that they roll along the ground before their big escape. Pachysoma, on the other hand, collects bits of dry dung and hoards it in a nest. The beetle goes on repeated foraging trips instead of one major journey.
Byrne and his colleagues from Lund University in Sweden think the species might have changed its mode of navigation because it needs to be able to find its way back and forth from its nest.
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"For most dung beetles, it's always a one way trip - grab the poo, run away and never go back," he explained. "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."
Prior research has found that ants count their steps as a way to navigate back and forth from home, and bees use the optical flow of scenery across their retinas to measure how far they've travelled to forage from the hive. Pachysoma dung beetles seem to be using a version of both techniques.