In the Mind of Plants
Jacques Mitsch (2009)
This documentary is about scientists who study plant intelligence. When this documentary was first released in six years ago, the notion that plants were intelligent was still extremely controversial. As you will note from the film, nearly all the research into plant intelligence occurs outside the US.
The impetus to study plant intelligence came from the 2002 discovery that rice has nearly twice as many genes (50,000) as human beings (26,000). Most scientists agree that species with more genes are more evolved. When it comes to adaptation and cooperation, there’s really no question that rice plants are more advanced than people.
The University of Bonn is the foremost center for the investigation of plant intelligence. While there are many different definitions of intelligence, the criteria used by Bonn scientists include the ability to assess and react to the environment, the ability to interact socially and the ability to form and retain memory.
Through their research, they have discovered that many plants respond to touch, hard surfaces, electrical charge, electromagnetic radiation and even music. Plants interact socially with other plants by emitting chemicals, either as gasses or through their roots. Carnivorous plants can remember being approached by a tasty insect for as long as an hour and acacia trees retain the memory of being attacked by grazing animals for even longer.
Much of this research is based on Darwin’s hypothesis that carnivorous and climbing plants have some kind of central nervous system that enabled them to make complex choices to aid in their survival. Bonn scientists have discovered a special zone of transition behind the root tip that continuously screens and adapts to information from the soil. This zone of transition functions in almost the same way as nerve synapses do in animals. Plant rootlets explore and process the space around them and make complex choices about how to survive, such as when to flower and when to become dormant.
When this zone of transition is excised, plants lose this ability.
The second video, which is more recent, explores how trees communicate with one other via the fungi that wrap around their roots, enabling them to transfer carbon and nitrogen to one another, based on which tree has the greater need.