How and why flowers develop their scent?
When a plant grows, it produces certain essential oils that decompose to form volatile oils. These oils are usually present in petals but they can also be found in fruits, leaves, barks and seeds. When the oil evaporates, the flower gives off smell. The type of fragrance depends on the chemical composition of the volatile oils.
No two flower species have the same scent although their colour and petal structure may look quite similar.
The purpose of the scent is to lure pollinators. Plant species pollinated by bees and flies have sweet scent while those pollinated by beetles have musty or fruity odours. Large flowers like Rafflesia arnoldii and Titan arum smell like decomposing corpses and the smell attracts their pollinators, the flies.
While some plants emit strong scents to keep animals away, the Venus flytrap uses its scent to attract insects which are then eaten by the plant!
