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Beetle feeding habits

strategy, used by so-called “rollers,” is for a female

or a pair (depending on the species) to form as

much dung as possible into a ball, often larger

than the beetles themselves, and roll it away from

the melee to a safe place, where it is buried and a

single egg laid inside. The dung beetle larva then

develops in safety surrounded by food in the ball

of buried dung, while the adults return to the pile

to repeat the process.

A single large ruminant such as a cow or an

antelope can produce 44–66 lb (20–30 kg) of

dung per day, and so the great herds, for example

of Africa, can support millions of individual dung

beetles of hundreds of species. In healthy,

balanced ecosystems, deposits of dung even from

large animals such as elephants may be cleared up

within minutes, refertilizing the soil in the process

VERTEBRATE DUNG

Being vertebrates ourselves, we might consider

vertebrate dung to be a worthless waste product,

but to many insects with finer digestive systems,

this mixture of incompletely digested food,

bacteria, and fungi is a valuable resource, and

hundreds of insect species have adapted to exploit

it. Chief among these are beetles.

Dung can be rather scarce and widely scattered

in the ecosystem, so a dung-feeding insect needs

well-developed senses to detect it quickly, and

good mobility to get to it while it is still available.

Scarab dung beetles (Scarabaeidae: Scarabaeinae)

use the scent-detecting flaps on their lamellate

antennae to sense dung over long distances, and

fly powerfully toward it. Dung beetles are so well

adapted that they can start arriving at a dung pile

within moments of it hitting the ground, and

immediately start to compete among one another

for this precious resource, which they use for

breeding as well as eating it themselves. One

below | Emus hirtus (Staphylinidae) Not all dung-associated

beetles are scarabs. This is one of the largest rove beetles and

a bumblebee mimic—it is a predator of fly maggots.