Recently I purchased a very unique houseplant. It is sensitive to the touch and in the evening folds its leaves together until sunrise of the next day. Its common name is the sensitive plant but its scientific name is Mimosa pudica. Mimosa in Greek means mimic and pudica in Latin means bashful, retiring.
According to sources there are over 300 different species of Mimosa, which belong to the (pea) Leguminosae family. This species, Mimosa pudica, is native to Brazil.
Mimosa pudica is considered a perennial, growing 18 inches outdoors. It is characterized by its hairy and spiny stems
and also produces a purple flower which gives rise to a small pod.
The plant’s unusual movement has fascinated people throughout time. At one point it was hypothesized that these plants had nerve and muscle tissue. A more realistic theory is that the movements are the result of a rapid loss of pressure in strategically situated cells that cause the leaves to droop. The exact mechanism of how the leaves loose their internal pressure has still yet to be discovered.
If you are looking to expand your plant collection consider the sensitive plant.
Source consulted: http://faculty.ucc.edu/biology-ombrello/pow/sensitive_plant.htm
Watch this plant in action: