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Certain plants noticeably change the position of their leaves according to the day-night cycle.
This movement is called nyctinasty. Leaves may fold together, droop, or rise as light conditions change, with internal biological rhythms also contributing to the behavior.
Prayer plants and several members of the legume family are well-known examples. A plant can therefore look noticeably different at midnight than it did during the afternoon.
© Royal Botanic Gardens, Kew