Meet the Dancing Plant. This peculiar shrub, native to Asia, has sparked the interests of botanists and others alike. The leaflets move in set elliptical patterns to help deduce the position of the sun (to appropriately expend energy moving the larger leaves where fitting). The intense fascination with these plants does not occur from its flowering habits, its peculiar “behavior”, or even its life cycle. The most intriguing thing about this plant is that it moves when stimulated by sound. Touching the plants will not cause the move, as Mimosa pudica (the Sensitive Plant) does. Changing the amount of light will not typically affect the elliptical movement of the leaflets. When exposed to sound, particularly high pitch (high frequency) sound waves, however, the plant’s leaflets and leaves move in a peculiar fashion. The leaves move dramatically enough, and quick enough, to be reasonably observed the human eye (time lapse photography or videos can show its movements even more so).
Besides being extraordinarily fascinating, the sensitivity to sound raises many questions. Why is this plant in particular sensitive to sound and not other environmental factors? What causes the plant to move so uniquely when exposed to sound, and does it improve its “dancing” through some faintly related type of memory? More importantly, what function does it serve? Moving in such conspicuous fashions would attract predators, herbivores, although it may ward off certain insects. Although it is likely that some complex chain of chemical reactions causes the plant to move, this is not entirely understood.
Codariocalyx motorius (Dancing Plant, Telegraph Plant) [formerly Desmodium gyrans]
Deciduous: In colder areas, Telegraph Plants go into dormancy. In warmer climates, though, it grows year-round.
Hardiness Zones: 10-11
Height: from 2 to 4 feet tall at maturity (rarely up to 1.5 meters)
Diameter: not specified
Growth Rate: fast, especially when young
Root System: The roots are used for Rheumatism.
Subspecies: var ‘glaber’
Tolerates: Generally pest free.
Problems (major): no major issues
Problems (minor): Aphids will sometimes attack the foliage of young plants. Overwatering may lead to root rot.
Poisonous: Yes, contains many toxic alkaloids.
Soil requirements: Clay (with full sun), sandy or loam (part-shade to full shade), requires a pH from 6.0-7.5
Air Requirements: not specified
Watering requirement: Prefers somewhat dry soil.
Sun requirement: full sun (if in clay), part-shade to full shade (sandy or loam)
Leaf shape: Leaves and leaflets are lanceolate shaped.
Leaf size: Lateral leaflets are 1 to 3 centimeters long and 3 to 5 centimeters wide. Terminal leaflets are 2 to 7 centimeters long and 6-13 centimeters wide. Leaflet stalks are roughly 3 millimeters long. The leaves are much larger, somewhere around 8-10 centimeters long (educated guess, insufficient data).
Flower structure: Tiny, 7-9 millimeters long. The flowers have sepal “cups”.
Flowering frequency: Telegraph plants almost never flower in their first year of life.
Bulb/tuber: neither, only roots
By far, Codariocalyx motorius is best known for its ability “dance”. The leaflets continuously move in elliptical patterns to search for sunlight. The information gathered by the leaflets is then used to move the larger leaves appropriately. Other than sunlight, these plants react to sound in a very apparent manner. The leaves will hover up and down when exposed to certain sounds, typically high-pitched noises. Strangely, Dancing Plants appear to improve their “dancing” the more they hear sounds, indicating the (unlikely) possibility that these plants have some type of memory. Serious consideration of plant intelligence, however, is not looked upon favorably by the scientific community (in part due to some absurd claims made in the past).
Typically used as house plants or specimen plants, primarily for their unique movement qualities.
A young Dancing Plant, no more than a foot tall
Several maturing (green) and mature (brown) seed pods of C. motorius (photo uploaded on 24 December 2012)
Multiple mature Telegraph Plant bushes (photo taken by Biswarup Ganguly, uploaded on 5 January 2013)
Leaves, leaflets, and stems of C. motorious (photo taken by Biswarup Ganguly, uploaded on 5 January 2013)
Black and white pictures showing the different positions the leaves can take (picture drawn by Paul Hermann Wilhelm Taubert (1862-1897), drawn in 1891)
Several black, bean-like seeds (photo uploaded on 24 December 2012)
A single, pinkish-white flower of C. motorious (image uploaded on 4 December 2012)
I do not own the rights of these images; all credit goes to its original creator(s).