Stand for a moment in front of a summer meadow and look at all the colours. Blue forget-me-nots, red poppies, bright yellow dandelions. It looks as if nature simply painted away with everything in its pencil case. But here is the question hiding in all that brightness: why are some flowers blue while others are red or yellow — and who exactly are they being so pretty for? The answer is not "for us". It is something far more surprising.
A flower's colour comes from tiny colouring substances, called pigments, inside the petals. Two families do most of the work. Anthocyanins give red, violet and blue. Carotenoids give yellow and orange — exactly the same substances that make a carrot orange. Which colour a flower ends up with depends on which pigments it makes, and how much of each.
Here is what surprises many people: the same pigment can make both red and blue. Anthocyanins change colour depending on how sour the "juice" inside the cells is. In sour juice they turn more red, in milder juice more blue. It is just like the way red-cabbage juice changes colour if you add lemon or baking soda — the same substance, a completely different result. Two flowers with the same pigment can end up blue and red, just because their cells are slightly different inside. Noticing hidden connections like this is exactly what STEAM learning is about.
But the biggest question is not how the colour is made — it is why. Why does a flower spend so much effort being colourful at all? Because the colour is not for us. It shouts in colour to the bees and butterflies: "come here, there is nectar!" The insect gets food, and the flower gets help carrying its pollen on so it can make seeds. The colour is a message — and it is not meant for us.
Try it at home. On a walk where flowers grow, draw as many different flower colours as you can, then sort them into two piles: "red, purple and blue" and "yellow and orange". Sit by a patch of flowers and watch which colours the insects fly to most. Count how many insects visit a blue or purple flower in five minutes, then compare with a yellow one — is there a difference in who comes? An adult stays with you; watch insects from a safe distance and never touch bees or wasps.
What happens if you lie completely still and follow just one bee for a while — does it visit any colour, or does it seem to have favourites?
Every child is made of good atoms. At Good Atoms we help them discover the hidden languages nature speaks all around us. Explore free content at goodatoms.com.