Looking at Insects Under a Stereo Microscope

“Entomology – the study of insects and their behaviour”

Looking at small insects under the low power stereoscopic microscope can be somewhat similar to viewing alien life form in close proximity and just as interesting. Kids as well as adults alike are always fascinated with the insect world. Most science classes in high schools and elementary grades will have at least a rudimentary study of insects and an introduction to entomology. There are over a million different kinds of insects on earth and more individual insects than all the other animals altogether. It would be easier to see how insects differ from each other by looking at them under the stereo microscope as well. It is possible to look at dead and live insects, so you could look at insects without killing them first.

However, it would not be easy to observe live insects under the stereo microscope because they move around a lot and it would be quite difficult to focus on them. In viewing live insects it would be ideal for the kid student to use a low power microscope. The stereoscope is a low power optical device. The compound light biological microscope is a high magnification optical instrument and is harder to use. It requires specimens to be flat on a microscope slide and has very little optical depth of field.

Let’s begin examining our tiny animals. It would help if the insect is just a small one, as well. You could make a slide trap where you could mount a small insect like an ant. This could be done by cutting a thick card the same size of a slide (you could trace around a slide to make sure of the size). Cut a slot in one side. Make sure that there is enough space in the slot to fit in a small insect and allow it movement. Keep the piece that you have cut out from the slot. Put a clean side on each side of the card and attach the ends with tape. Lift the top slide and put a small insect inside the gap that you have cut out. Replace the top slide over the thick card and push the piece you have saved from the card back into the slot to trap the insect. View the insect with a low power stereo microscope and top lighting.

But looking at bigger insects under the stereo binocular microscope can be difficult. So if you want to look at insect parts more closely, it would be better to remove it from the whole and mount it on its own. You could look at the parts when they are dry, but it is usually better to make a temporary mount. This would require you to prepare the insect first.

To prepare an insect to look at under the stereo microscope, the student should follow these steps:

1. Soften the insect by soaking them in washing soda solution for a couple of days.
2. You could prepare the solution by pouring 100ml water into a jar and stirring in 100g of washing soda. Put any insect you want to view in this solution and leave them for a couple of days.
3. Handle the insects carefully with tweezers and make sure to wash your hands clean afterwards.
4. Rinse the insects when you take them out of the solution.

To remove the parts of an insect, get two pairs of tweezers and use a mounted magnifying glass to look through while doing the dissecting. Try to see if the insect that you are going to mount looks better on its side than on its front or the back.

To remove a part of an insect and prepare it to mount on a microscope slide, follow these steps:

1. Hold the insect with one pair of tweezers and pull away the body part that you want to view with the other pair of tweezers.
2. Use mounting needles to place the part that you have taken away from the insect on a microscope slide.
3. If viewing under the stereoscope, you don’t need a cover slip. But if you want to also view the specimen using a compound microscope, you need to put on a cover slip. In that case, push the cover slip down carefully to flatten the insect part against the slide. This makes it Easier to focus as a compound microscope has a limited depth of field.

Students and science teachers alike will find it interesting to view the micro insect world with the aid of low power stereo microscopes.

This can be one of the simpliest and rewarding science activities for students in a high school biology classroom.