Teaching Sequence

Work through this resource material in the following sequence:

20 minutes

Tune in: What will change?

20 minutes

Find out: Experiment time!

20 minutes

Reflection: What did we learn?

Tune in: What will change?

Step 1.

Discuss with students why flowers need to attract insects. They might have some understanding of the process of pollination.

Step 2.

Now discuss what makes flowers attractive to insects. Is it their colour, size, shape?

Step 3.

Students write their predictions in the first section of the Student Worksheet.

Find out: Experiment time!

Step 1.

Cut two pink and two white flowers out of the card.

Step 2.

Draw red ‘honey guides’ on the two pink flowers and black ‘honey guides’ on the two white flowers (see diagram below).

Step 3.

Cut four short lengths of wire (10-15cm) and stick one end of the wire to the backs of the flowers with sticky tape.

Step 4.

Place the flowers in the ground outside so they stand independently.

Step 5.

In the centre of each flower place a blob of honey.

Step 6.

Stand back (at least a metre) and wait to see if any insects visit your flowers. Which flowers appear to be the most attractive; the pink or the white?

You might have to set up a camera, or check on the flowers periodically to see which patch of honey is disappearing more over time.

Reflection: What did we learn?

In nature, flowers come in all sorts of shapes, sizes, scents and colours.

They have evolved this way in an attempt to attract as many insects as possible, or to attract a particular insect who will assist in completing the life cycle of the flower by transferring pollen from flower to flower.

Flowers need insects to transfer pollen between flowers because this process, called pollination, is essential for the sexual reproduction of many flowering plants.

Did you know that flowers can be both male and female? The male reproductive structure is called the stamen and it produces pollen. The female reproductive structure is called the pistil and it contains the ovules.

In order for fertilization to occur, the pollen from the male reproductive structure must reach the female reproductive structure.

This is where insects come in. Insects such as bees, butterflies, and moths are attracted to flowers by their colours, scents, and nectar. As they land on the flower to collect nectar, the pollen sticks to their bodies. When the insect visits another flower of the same species, some of the pollen rubs off onto the stigma, the sticky tip of the female reproductive structure, thus achieving pollination.

Without insects, many flowering plants would not be able to reproduce, leading to a decline in their populations and potentially affecting other organisms that rely on them for food or habitat.

It's worth noting that the specific preferences of different insect species can vary widely.

However, in general, many insects, including bees and butterflies, are more attracted to pink flowers than white flowers. There are several possible reasons for this:

Colour contrast: Pink flowers often stand out more against a green background than white flowers, making them easier for insects to see and locate.
Scent: Some pink flowers, such as roses, have a stronger scent than white flowers, which can be more attractive to some insect species.
Nectar content: Insects are often attracted to flowers with higher nectar content, and some pink flowers, such as salvia and bee balm, have more nectar than white flowers.
Ultraviolet (UV) reflection: Some studies have suggested that pink flowers reflect more UV light than white flowers, which can make them more visible and attractive to some insects, which can see in the UV spectrum.

What Colours Do Insects Like?

Summary

Lesson Guides and Printables

What Colours Do Insects Like?

Summary

Lesson Guides and Printables