Department of Environment and Heritage Protection
Junior Ranger program
Lesson Plan
Insect collecting
Purpose
Students will learn about identification and the classification of insects. Insects have adaptations that enable them
to thrive in northern Australia.
Links with Australian Curriculum
Year 5 Science Strand: Understanding Science
Substrand
Living things have structural features and adaptations that help them to survive in their environment.
Elaboration
• Describing and listing adaptations of living things suited for the Australian environment.
• Exploring general adaptations for particular environments such as water conservation in deserts.
• Explaining how particular adaptations help survival such as nocturnal behaviour or silvery-coloured leaves
of dune plants.
• Comparing types of adaptations such as behavioural and structural.
Students will be introduced to insect collection techniques and will attempt to key out insects to ‘order’ level.
Students will recognise distinctive features of insect orders and attempt to identify adaptations that enable insects
to flourish in the northern Australian environment.
Activity: Insect capture techniques and identifying insects
Students will identify and record key adaptation features of insects. Students will also learn to use dichotomous
keys and key an insect out to order level.
Procedure
Have a safety discussion with students regarding the use of the pooter (see page 2) as well as handling insects.
Points to remember include:
• be careful not to swallow the insects
• the pooter has glass components and will break if dropped
• some insects will bite or sting if mishandled.
Using a variety of insect-collection techniques, capture a sample of insects in a number of different locations.
30765
What you will need
• Insect identification and classification key (see web links below).
• Various insect collection devices—e.g. pooter, coloured dishes filled with water and detergent, fiji trap,
butterfly net, white sheet and fly spray. (Lay the sheet out under a small tree and see what drops out after
a quick burst of insect spray).
Some insects are very small so use a magnifying glass or other form of magnification to distinguish features on
the specimen.
Students examine the insects that they have captured. Can some arthropods be immediately excluded as not being
insects (e.g. spiders, mites, crustaceans)? What is an insect and how is it different to other arthropods?
Students identify key features in a particular specimen. Draw a sketch of the animal and label its features.
How is this animal adapted to the environment?
Students use a dichotomous key to identify the insect to ‘order’ level.
Resources
You need the following to make a pooter:
•
•
•
•
A jar with two holes drilled into the lid.
Two lengths of plastic tubing.
Gauze to cover one end of the pipe so you don’t swallow the bugs.
Some poster putty to seal the holes in the jar lid.
Class discussion points
Insects can be classified into different groups based on differences
and similarities of morphological features (body shapes).
What features do insects have in common with humans?
The pooter
What features to insects have that make them different
to us?
Engaging phase
Based on existing prior knowledge, students draw a basic body plan of an insect.
What are the features you might expect to see on an insect?
•
•
•
•
•
wings (compare with the wings of a bird. Discuss how this is an analogous feature—wings are modified limbs)
bi-symmetrical body plan (compare to jellyfish and starfish, which have radial symmetry)
single pair of antennae (compare to crustaceans, which have two pairs)
a pair of compound eyes (may also have simple eye spots as well, as in the case of the paper wasp—Polistes sp)
segmented body (3 segments—head, thorax and abdomen. Compare this with the millipede, which has many
serially repeated segments, or flatworms, which are not segmented)
• exoskeleton (compare with human internal skeleton)
• complex mouth parts and appendages (compare this with a vertebrate mouth, which has a simple jaw
mechanism and fleshy lips). See the text box ‘Sucker or chewer?’
• brain and nervous system (insect brains are connected to two nerve bundles called ganglia that run down each
side of the body. Compare this with the human central nervous system)
Insects are the most successful life form on the planet. About one half of all described species are insects
(750 000 insects compared to 250 000 plants, 4000 mammals, 20 000 fish and 6300 reptiles).
2
Ask students to catch as many different types of insects as they can and see if they can identify them to ‘order’
level. Ask them what features they will examine to tell the insects apart?
Look for these features
•
•
•
•
•
•
Presence or absence of wings
Number of pair of wings
Mouth part is a tube for sucking
Hard wing shied
Leg shape
Scales and veins on wings
Classifying insects
Order:
•
•
•
•
•
•
•
•
•
•
•
Diptera—flies and mosquitoes
Coleoptera—beetles
Hemiptera—true bugs (sucking mouth parts), such as aphids and stink bugs
Blattodea—cockroaches
Mantodea—praying mantis
Orthoptera—grasshoppers and crickets
Lepidoptera—butterflies and moths
Hymenoptera—bees, ants and wasps
Odonta—dragonflies
Isoptera—termites
Neuroptera—lacewings (antlion larval stage is probably more familiar)
Scientists use dichotomous keys to identify insects. A dichotomous key is like a flow diagram where you follow a
string of yes or no answers, with each step bringing you closer to the identity of your species.
Resources
• http://www.entomology.edu.au/insects-school
Insect keys
• www.amnh.org/learn/biodiversity_counts/ident_help/Text_Keys/text_keys_index.htm
Insect farms
• www.insectfarm.com.au
3
Extension Activities:
Now that students have had some practice with keys and are aware of their purpose and features, students can try
making their own dichotomous key. Students should make a key that identifies each person in the class.
Students with the use of art supplies and the aid of the sketches they have made make a “big bug” (i.e. large-scale
model of an insect) using whatever materials are at hand (clay, drinking straws, papier mache, ghost nets, etc.).
Butterfly or moth?
Is it a butterfly or is it a moth? What are the differences between the two?
Look at antennae shape, wing structure, resting posture, forelegs, pupae, and active times of day or night.
10mm
Zodiac moth
4 o’clock moth
Did you know? Butterfly eyes are secondarily diurnal—that means their vision is was initially adapted to seeing
at night time (like a moth’s) but has since evolved through natural selection for daytime use. You can read more
at <rspb.royalsocietypublishing.org/content/273/1587/661.full>.
All butterflies have clubbed antennae (a small knob on the end) and do not possess a membrane called a
frenulum (a device for locking the front and back wings together like moths have).
4
Sucker or chewer?
Insects have complex mouth parts that are finely adapted to particular food sources. The different insect orders
often have specialised mouth parts that dictate the sort of food they can eat. They are either suckers or chewers.
Based on the insects you have collected, are the following insect orders suckers or chewers?
• Diptera—flies and mosquitoes_ __________________________________________________________________
• Coleoptera—beetles____________________________________________________________________________
• Hemiptera—aphids and stink bugs________________________________________________________________
• Blattodea—cockroaches_ _______________________________________________________________________
• Mantodea—praying mantis______________________________________________________________________
• Orthoptera—grasshoppers and crickets____________________________________________________________
• Lepidoptera—butterflies and moths_______________________________________________________________
• Hymenoptera—bees, ants and wasps______________________________________________________________
• Odonta —dragonflies___________________________________________________________________________
• Isoptera—termites_ ____________________________________________________________________________
• Neuroptera—lacewings
(antlion larval stage is probably more familiar)______________________________________________________
5
Student handout
Catching insects
Student name:
There are many ways to catch and collect insects.
One fun way is to use a pooter which you use to
suck up insects that are perched (or if you’re really
quick you can catch in mid flight). Once they are
safely in the jar you can study them knowing that
they are safely contained. Once you are finished
with the insect you can let it go in the same place
you found it.
Safety tips for using a pooter:
The jar is made of glass and can break if you drop it
Make sure the gauze is securely in place. Do not blow down the tube.
Some insects use chemical defences against capture and predation. Some ants will excrete formic acid; other
insects can release offensive odours (e.g. stink bug). Be careful about the types of insects that you pooter-up.
Draw a picture of an insect that you have captured. Label your picture and give it a title. Identify which order the
insect belongs to. Based on its features what do you think the animal eats (is it a sucker or a chewer?). What special
adaptations can you identify?
29887
6