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Beetle feeding habits

plant matter, so dead plant tissue was the likely

ancestral food of Coleoptera.

Dead plants should not be regarded as a

single uniform resource; they consist of a whole

progression from fermenting fruit to hard, dry

timber. Vegetation decays in stages, from freshly

dead and still green to humus and litter that is

almost indistinguishable from soil, and all of

these stages are utilized by different groups

of beetles.

The hardest and most indigestible dead plant

matter is the wood from the stems and branches

of large trees, but beetle larvae of several families,

notably Cerambycidae, Buprestidae, and Ptinidae,

specialize in this and play an important role in

breaking it down. If the wood becomes very dry,

for example in a standing dead tree, or wood that

has been made into furniture or structural timber,

fungal and microbial activity almost shuts down,

and very little nutrition remains for any beetle

DEAD AND DECAYING PLANT TISSUE

Plants make up most of the living biomass of the

world’s land ecosystems, and when they die they

provide a vast food supply for other creatures,

which break them down into nutrients used by

other plants, so completing biological nutrient

cycles. Compared to live vegetation, dead plants

do not defend themselves with chemicals and are

much more easily digested, so the range of beetles

able to feed on them is much greater than when

they were alive. Also, as soon as plants begin to

decay they are invaded by huge populations of

fungi, bacteria, and nematode worms, and many

beetles that feed on dead plant matter are actually

obtaining most of their nutrition from digesting

other detritivores, rather than directly from the

plant itself.

Judging from their closest living relatives, the

larvae of the most ancient known beetles, from

the suborder Archostemata, probably fed on dead

right | Lethrus apterus

(Geotrupidae)

A flightless relative

of dung beetles from

Europe that collects

dead leaves to feed to

its larvae.