What is the role of pubescence of stems, leaves, fruits and seeds of plants?

1) The hairs on the leaves and stems protect from drying out, reflecting light, reduce radiation, reduce evaporation, creating a semi-closed layer of air.
2) Hard hairs and burning hairs can protect against eating (nettles).
3) Feathered fruits and seeds are easily attached to animal hair or carried away by the wind (dandelion, poplar, etc.)

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