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14
BULLETIN OF THE UNIVERSITY OF NEBRASKA STATE MUSEUM
of north-central Nebraska. Ponderosa pine
(Pinus ponderosa Lawson) and narrow-leaf
cottonwood (Populus angustifolia James)
are common Rocky Mountain trees that
are found in this region of the state. Quaking
aspen (Populus tremuloides Michaux)
and western black birch (Betula fontinalis
Sargent) also indicate the montane floral
affinities of the Pine Ridge. These species
probably occurred widely over much of the
western part of the state in post-Wisconsin
times, and the areas that remained when
Europeans first reached western Nebraska
were relics of this former widespread distribution
(Jones 1964). The large influx of
settlers since that time has altered considerably
those remaining forest relics which,
today, are disturbed remnants of the former
plant associations.
Fig. 14. Rocky Mountain forest near Chadron in
Dawes Co. in northwestern Nebraska. Photo courtesy
of NEBRASKAland Magazine/Nebraska Game and
Parks Commission.
The SIlPhIDAe
The spectacle of nature is always new,
for she is always renewing the spectors. Life
is her most exquisite invention, and death
is her expert contrivance to get plenty of it.
— Goethe
Carrion beetles is the term applied, in
a strict sense, to a single family of beetles,
the Silphidae. Silphids are also generally
referred to as burying beetles or sexton
beetles because of the behavioral adaptations
of Nicrophorus species to inter small
vertebrates in the ground.
Silphids are relatively large beetles,
ranging in size from 10 to 35 mm. The majority
are usually a dull black or grey in color,
but most species in the genus Nicrophorus
have bright orange markings on the elytra
that may serve as warning coloration.
Most silphids occur in north temperate
regions, which is where they probably originated
(Peck and Anderson 1985, in part).
The majority of silphids are scavengers on
carrion, and a few are found on dung or fungi,
are phytophagous, or prey on fly larvae.
Carrion beetles are a conspicuous
element of that vast host of scavengers
that are responsible for breaking down
and recycling back into the ecosystem the
basic elements found inside of each organism.
The decay process is an efficient and
natural system whereby the raw materials
of dead organisms are returned directly
into the energy budgets of living organisms
when they consume the dead ones.
Once an animal dies, its remains are
ravenously set upon by a diverse array of
food-seeking scavengers and predators that
are attracted by the odors of decay. Assuming
that vertebrate scavengers do not find
and consume the remains first while they
are still fresh, the remains will become a
valuable food resource for a reasonably orderly
progression of bacteria and fungi (the
microconsumers) and insects (the macroconsumers)
(Ratcliffe 1980). The progression of
insects is fairly predictable because specific