Identifying Invertebrates Using a Key

JSSS Teacher support material

Investigation 3

Identifying invertebrates using a key

Students work through a key to simple invertebrates. Students may work with live samples, preserved samples, plastic models, photocopied images or projected images.

Some students may need to be led through the key with an example and should then be able to key out a range of organisms for themselves. The example of the common earwig (O’Connor and Ashe, Irish indoor insects) is keyed out here.

PincerAntenna

Leg

1 Legs? No Go to 2

Yes Go to 5

Once the student sees the difference between antenna, pincers and legs, they are off to 5.

5 Six legs? No Go to 6

Yes Insect

When the legs have been counted, the student has successfully keyed out the earwig as an insect!

The student notes also contain a simple key to trees. This very simple key will help students to identify five common trees using the winter twig as the sample.

Éanna Ní Lamhna’s Transition Year book, ‘Be an Environmental Scientist’ contains an excellent detailed key to common invertebrates. Links to excellent interactive websites for tree identification can be found at www.juniorscience.ie.

Investigation 4

Identifying plants and animals in local habitats:

Each group needs:

·  a variety of plant and animal keys suitable for the local area;

·  a variety of suitable collecting equipment – pooter, bucket, specimen jars, plastic bags, forceps, etc.;

·  a variety of suitable viewing equipment – nature viewers, bug viewers, magnifying glass, etc.

Each student needs:

·  suitable clothing;

·  clipboard, pencil;

·  copy of worksheets 1 and 2.

Teacher preparation

·  Give clear instruction to each group:

a.  set the limits of the work area

b.  observe the variety of the living things you observe within the area

c.  return each organism to the habitat when finished identifying and drawing.

·  Set an appropriate time limit.

·  Either circulate among groups to help, or remain in a designated area so that students know where to go to ask questions.

·  If there is a digital camera available, the students' activity can be recorded for display purposes, and photographs taken of the living things observed in situ. It is particularly useful for recording images of species not covered in the keys taken to the field, so that they can be later identified in the lab.

Safety considerations

Teachers should follow appropriate safety procedures in carrying out the activities described in this section.

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