Scientists have discovered that three species of dung beetle walk with a "galloping" gait not seen in any other insect.
The vast majority of insect species walk with what is known as an alternating tripod gait - steadily moving forward three legs at a time.
It is not clear why these flightless beetles have shifted so radically from the usual way of walking.
The findings are reported in the journal Current Biology.
The researchers wrote: "Like a bounding hare, the beetles propel their body forward by synchronously stepping with both middle legs and then both front legs."
They beetles appeared simply to "drag" their back legs, they added.
Dr Jochen Smolka, from the University of Lund in Sweden, who carried out the research in South Africa, was studying wingless desert dung beetles in order to find out how they navigated to their burrows.
"We noticed that [one species we were looking at] was kind of bobbing along in a peculiar manner," he told BBC News.
