Sydney NSW, Australia
For your information
Dung Beetles Use the Sky to Navigate – but How Exactly?


A pair of dung beetles. Photo: Kev Gregory/Flickr

Placed over the heart in the wrappings of Egyptian mummies, archaeologists have often found carved amulets of scarab beetles, a species of dung beetle. The amulets, many with spells inscribed on them, were intended to help the dead in a final judgment by the jackal-headed god of death, Anubis, who would weigh the hearts of the deceased to assess whether they were worthy of the afterlife.

The ancient Egyptians also believed that a dung beetle drove the movement of the sun, because the sacred scarab (Scarabaeus sacer) — which sculpts dung into balls for meals, gifts for potential mates or repositories for eggs — rolls the balls across the ground in a manner that reflects the sun’s journey across the sky.

In fact, it’s the sun that steers the movement of dung beetles. And so does light from the moon, and from the distant stars of the Milky Way. With a life devoted to excrement but guided by the heavens, dung beetles might embody the famed Oscar Wilde quote, “We are all in the gutter, but some of us are looking at the stars.”

“Tiny brains can solve fantastic tasks,” says neurobiologist Marie Dacke of Lund University in Sweden, one of a small cadre of researchers who have worked for years, often as a team, to piece together the tricks the insects use to roll balls in their eerily straight lines.

The best escape

Roughly 600 of the 8,000-plus known dung beetle species roll such balls, scurrying away from mounds of animal dung with spheres of excrement for about six minutes before they bury the balls, along with themselves, so they can dine underground in peace. (Many more species don’t roll balls, but stow dung away in long tunnels burrowed directly under dung pats.)

To keep their cargo from getting stolen by rivals, ball rollers have evolved to escape from dung piles in the fastest, most efficient way possible — a straight line, as the scientists describe in an article in the Annual Review of Entomology.

Read on:


No responses yet...