How Strong Are Dung Beetles?

The strongest horned dung beetle measured could resist a pull equal to 1,141 times its own body weight. That record belongs to a male Onthophagus taurus, a small tunneling species. It is an extraordinary result, but it does not mean every dung beetle can lift that much or roll a dung ball that heavy.

What Does 1,141 Times Body Weight Mean?

The figure is a ratio between the beetle’s maximum pulling force and its weight. At human scale, a 154-pound person matching that ratio would resist roughly 176,000 pounds, or 88 US tons. That comparison helps make the number visible, though the physics does not let an insect keep the same relative strength if it is enlarged to human size.

There is another qualification. The original strength study reported the highest result from its test, not an everyday load carried by all dung beetles. Species, body size, sex, horn length, nutrition, and the job a beetle performs can all affect its strength.

How Did Scientists Test a Dung Beetle?

The test copied a struggle inside a breeding tunnel. In the tunnel test, researchers attached cotton thread to the rear wing covers of each male, then let him crawl into an artificial passage lined with fine sandpaper. The passage was 4 millimeters high, 7 millimeters wide, and tilted about 60 degrees from horizontal.

Once the beetle had entered, the thread ran over a pulley to a small hanging container. Water was added at a steady rate until the beetle lost its grip and came out of the tunnel. Researchers converted the final load to force, tested each male three times with at least 10 minutes between trials, and used his highest result as maximum strength.

So the record describes pulling resistance while the beetle was braced against a rough surface. Calling it a lift loses the most useful part of the experiment.

Why Do Dung Beetles Need That Strength?

For the large, long-horned males of Onthophagus taurus, strength helps win access to a mate. Females dig tunnels beneath dung, and a major male guards a female inside. When another major male enters, the two lock horns and try to push each other out.

This is not a decorative contest. A later University of Western Australia study found that strength and body mass both predicted which male won a fight. Horn length did too. Smaller, short-horned males use another tactic. They enter when a guard is distracted or dig a side tunnel, so they do not make the same investment in fighting strength.

Food mattered too. In the original experiment, five days without food sharply reduced strength in the long-horned males that fight. The short-horned males showed little change. Muscle has a cost, and it pays only when a beetle’s mating strategy calls for it.

Can They Roll a Ball 1,141 Times Their Weight?

No. The record-holder is a tunneler, and the test measured how firmly it could resist being pulled from a passage. Ball rolling is a different task. A beetle has to get a shifting load moving, then steer it over uneven ground without losing control.

Rollers still move startling loads. The Natural History Museum reports an extreme ball weight of 79 times the beetle’s body weight. Those balls serve as food or as provisions for developing young. The details make more sense once you know what dung beetles eat.

Why Are Small Beetles So Strong?

Small size changes the ratio between muscle force and body weight. Muscle force depends largely on cross-sectional area, which rises with the square of an animal’s length. Body mass rises with the cube. A University of Wisconsin explanation shows that, for similarly shaped animals, strength relative to weight increases as body length decreases.

The beetle also gets excellent traction in a close tunnel. Its legs can press against rough walls while its body blocks much of the passage. The muscles and rigid outer skeleton work especially well in that setting, but small scale is the reason the body-weight comparison becomes so large.

This also explains why a person-sized dung beetle would not pull 1,141 times its new weight. Its mass would grow faster than the cross-sectional area of its muscles. The bus comparisons are thought experiments, not blueprints for a giant beetle.

Are All Dung Beetles Equally Strong?

Not close. Scientists have recorded about 9,500 dung beetle species, ranging from tiny dwellers that live inside a dung pat to rollers and powerful tunnelers. Their bodies reflect different work. Even within Onthophagus taurus, the original research found wide differences between males.

The honest answer is that dung beetles are exceptionally strong for their size, and one horned tunneler produced a 1,141-body-weight record under a specific test. Keep the species, the measurement, and the tunnel attached to the number. It is impressive enough without turning every dung beetle into a miniature forklift.

Sources

• Queen Mary University of London, “Pulling Power Points the Way to the World’s Strongest Insect”
• Knell and Simmons, “Mating Tactics Determine Patterns of Condition Dependence in a Dimorphic Horned Beetle”
• Natural History Museum, “How Do Dung Beetles’ Diets Keep the World Clean?”
• University of Western Australia, “Selection on Male Physical Performance During Male-Male Competition and Female Choice”
• University of Wisconsin, “Scaling of Strength”