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long distances. So if the insect were too large, then all of the body parts would be
constantly under-supplied with oxygen. Consequently, insects' size must remain
within certain limits.
Insect Wings
It goes without saying that we only use already dead animals for the examina-
tion of insects. For example, you will find plenty of material for observation on
cellar steps, in spider webs, windowsills, or on the radiator grille of automo-
biles. To observe an insect wing, you will need:
• a slide and a cover slip
• tweezers (your tweezers will work here, too, but so-called spring steel twee-
zers are even more practical for working with insects)
• an assortment of insect wings
Insect wings can also be laid dry on the slide and, as needed, covered with a
cover slip so that they are not blown away by a breath of wind. Both observa-
tion methods (transmitted light microscopy and magnifying glass mode with
incident light) give interesting results here. Besides the wing veins, you can
also discover other things on the wings. Very often, the wings of insects are
covered, for example, with tiny hairs. Butterfly wings also have many colorful
scales on them.
Sting, Bite, or Lick?
As varied as the living spaces of the insects are, the insects themselves are of
course just as varied. One of the few characteristics that they all have in common is
this: All insects have six legs (spiders have eight legs and therefore are not includ-
ed among the insects). When they don't happen to be flying, then they're moving
along on their six legs in search of food. There are several unique features here
too. Insects take in their food with their specialized mouthparts which, inciden-
tally, are not in the mouth — as they are in humans — but rather in front of the
mouth. Depending on what kind of nourishment the insect prefers, its mouthparts
are also adapted to their respective requirements.
A butterfly feeds from the nectar of blossoms, which is sometimes buried deeply
in the blossoms. Consequently, it needs a long proboscis with which it can suck its
food from the hidden corners of a bloom. To keep the proboscis from getting in
the way during other activities, the butterfly rolls it up like a fire hose. The mos-
quito also uses sucking to feed — but in this case, it's the blood of other animals.
First, however, it has to poke through the tough skin of its victim in order to get
at the desired juice. The mosquito's mouthparts are specifically designed for both
poking skin and sucking up liquid food. Ant soldiers possess true pincers with
which they can fight, break things down, or carry things.
Mouthparts of Insects
Use your microscope to have a closer look at the variety of mouthparts of vari-
ous insects. You will need:
• a slide
• tweezers
• the dissecting needle
The objects are generally too thick to fit under a cover slip. For this reason,
simply place your object on the slide and observe it at the lowest magnifica-
tion (40x). Here your microscope proves itself as a true jack of all trades! This is
because you now have the possibility of looking at the object with the magni-
fying glass (with incident light) or the microscope (with transmitted light). Try
it out and, in that way, gain the best possible insight into the mouthparts of
the insect you're studying!
Can you match the mouthparts under the microscope up with one of the types
just presented?
Veins of
an insect
wing and
butterfly
wing
scales
The proboscis of a butterfly
The mouthparts of an ant
The biting apparatus of a mosquito
Did You Know?
Only female mosquitoes suck blood.
They need our blood to feed their
young. Although the little males do
possess biting and sucking mouth-
parts, they only use them to poke
into plants and suck out the juice.
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