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Beetles and humans

dark, dry places full of a single kind of food—are

not unique in the natural world. Some birds such

as jays hoard seeds in hollow trees; rodents such

as squirrels, mice, rats, and hamsters store grain

in their burrows, and it is thought that some of the

most serious pests of grain storage were originally

associated with the underground larders of

small mammals.

To be associated with stored products, beetles

need three main characteristics: to be resistant to

dry conditions as adults and larvae, since stored

products are, where possible, kept dry; have the

ability to disperse over large distances, as supplies

of food are scattered in the environment; and for

the same reason, like any animal needing an

infrequent resource, be able to detect reliably the

resource that they will infest. Families of beetles

that meet these criteria, and members of which

have become cosmopolitan stored product pests,

include Tenebrionidae, Laemophloeidae,

PESTS OF STORED

AGRICULTURAL PRODUCTS

With the agricultural revolution, or even earlier

with hunter-gatherers, people stored food from

times of plenty for future times of need. Like

almost every activity, this practice provided

opportunities for beetles to exploit. When people

travel from place to place, especially large groups

over great distances, they usually bring a supply of

preserved food for the trip. If food is carried for

periods of time in open conditions, or by ship, it

might get damp or spoiled, and on reaching the

destination will be discarded, distributing any

insects it contains into a new environment. As

humans have spread all over the world, the insect

travelers associated with their food supplies have

been carried with them, and at each destination,

more species were picked up accidentally and

added to the assemblage of “human stored

product beetles.”

In this way, numerous beetle species that feed

on preserved or dried grain, fruit, fish, or meat

have been spread throughout the populated

world. Remains of the exact same pest species

have been found preserved in the pyramids

of ancient Egypt and in Native

American archeological sites, showing

how long they have been with us and

how far we have traveled together.

The original ranges of these beetles

are lost in time, but we can infer

their original habitats, since humans

are not the first animals to store

products, and the habitats provided

by human food storage—effectively

right | Oryzaephilus surinamensis (Silvanidae)

The earliest known record of the

cosmopolitan Saw-Toothed Grain Beetle

is from a Neolithic site in northern Greece.