Flowering plants belong to a group called angiosperms and the first flowering plant existed somewhere around 160 million years ago. Since then, flowering plants have become extremely diverse, as we can see today in their range of shapes, colors, sizes, and smells.
Many flowers derive their colors from the production of pigments called anthocyanins (red, pink, purple, and blue in particular).
The Foldscope was used to view a slide of a Geranium flower petal at different magnifications and a cell phone recorded the images. This Geranium flower gets its purple pigment from anthocyanin, which can be seen occupying most of the volume of the cells (140 X and 480 X on the right).
So why do plants have color? In nutshell, it’s for sex. Plants can’t go anywhere, so they need help to disperse their genetic material and pass on their traits to the next generation. Some plants utilize the wind or other indirect methods for transfer, while other plants recruit animals to aid in the reproductive process. Bright colors in flowers can act to attract birds, bees, and other insects which visit multiple flowers and spread pollen (containing the plant gametes, or sperm cells) along the way.
There you go – a quick and dirty explanation of flower color and a cool little experiment with the 50-cent paper microscope!
-Aaron
You can follow me on Twitter @AaronPomerantz and the Foldscope researchers @PrakashLab