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Somewhere near you, 
an animal is defecating.

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In fact, each day, the animal kingdom 
produces roughly enough dung

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to match the volume of water pouring 
over the Victoria Falls.

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So why isn’t the planet covered 
in the stuff?

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You can thank the humble dung beetle 
for eating up the excess.

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Capable of burying 250 times 
their body weight in a single night,

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these valiant insects make
quick work of an endless stream of feces.

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Over 7,000 known species of dung beetle 
run clean-up duty across six continents

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—everywhere except Antarctica.

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A dung beetle’s first task 
is to locate dung.

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Some live on the anal regions 
of larger animals,

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ready to leap off when they defecate.

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Others sniff out feces 
that animals leave behind.

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A pile of elephant dung can attract 
4,000 beetles in 15 minutes.

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So once a beetle finds dung,

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it must work quickly to secure 
some of the bounty for itself.

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Most dung beetle species fall into one 
of three main groups:

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rollers,

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tunnelers,

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and dwellers.

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Dung rollers sculpt a ball of dung,
and using their back legs,

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quickly roll it away from competitors.

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Potential partners jump on the ball,

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and once the ball-maker 
has selected their mate,

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the pair dig their dung ball 
into the soil.

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Once it’s been buried, the female lays 
a single egg within the dung ball.

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Tunnelers have a different approach.

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Digging underneath a pat, 
some drag dung down into the soil

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and pack it into clumps 
known as brood balls,

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dung balls,

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or dung “sausages,” 
depending on their shape and size.

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Male tunnelers sport a spectacular 
array of horns

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to fight each other
for control of these tunnels,

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which they then defend 
until the female’s laid her egg.

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Some male tunnelers avoid the fray
by masquerading as hornless females

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and sneaking into tunnels to mate 
while the guardians’ heads are turned.

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The third group of dung beetles, dwellers,

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take the most straightforward approach,

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laying their eggs
directly into a dung pat.

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This makes their offspring
more vulnerable to predation

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than those of the tunnelers and rollers.

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As the larvae feed, they riddle 
the dung pat with tunnels,

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leaving remains that are quickly colonized
by bacteria and fungi and weathered away.

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Inside a tunnel, ball, or pat, 
once the larvae hatch,

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they consume the dung 
before metamorphosing into a pupa

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and then an adult beetle.

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Besides clearing dung, 
the actions of these beetles

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have considerable ecological importance.

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For one, they serve as secondary 
seed dispersers.

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Dung from monkeys,

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wild pigs,

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and other animals is riddled with seeds 
from the fruits they eat.

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When beetles bury their dung balls,

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they inadvertently protect these seeds 
from predators

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and increase the likelihood 
they’ll germinate.

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The advantage is so great 
that one South African plant

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has evolved to produce seeds that look 
and smell like dung

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to trick beetles into burying them.

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Dung beetles also play important roles 
in agricultural systems.

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Livestock, like cows and sheep,
produce huge amounts of dung,

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which contains nutrients 
that can benefit plants.

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The beetles break up the dung 
and tunnel it deep into the soil,

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bringing the nutrients into close contact
with plant roots.

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Their services to farmers have been valued
at $380 million a year in the US

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and £367 million a year in the UK.

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Dung beetles can even help us battle 
global warming

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by reducing greenhouse gas emissions
associated with farming.

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Microbes living in oxygen-poor 
livestock dung

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produce methane, a potent greenhouse gas.

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But beetles oxygenate pats when 
they tunnel into them,

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preventing the microbes
from producing methane.

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The dung beetle spreads seeds,

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helps farmers,

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and fights climate change

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—and accomplishes it all
simply by doing its business.

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Maybe next time you come across 
some dung in the forest or a field,

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you’ll be tempted to take a closer look.