The Secret Life of Plants is a 1979 documentary based on the 1973 book of the same name by Peter Tompkins and Christopher Bird. Described as “A fascinating account of the physical, emotional, and spiritual relations between plants and man,” the book—and the film—explore the hypothesis that plants are sentient, despite their lack of a nervous system and a brain. Sentience is demonstrated primarily through changes in the plant’s conductivity, as measured through a polygraph in experiments pioneered by Cleve Backster. Time-lapse photography shows the pain and joy plants experience and how they communicate it.
Although the film—and even more so, the book on which it is based—drew criticism as “pseudoscientific,” more recent plant science has revisited some of the book/film’s claims—and even extending them. Renowned food writer Michael Pollan summarized some of this research in a December 23, 2013 article in The New Yorker entitled “The Intelligent Plant.” Pollan referenced an article by six plant researchers—among them Eric D. Brenner, an American plant molecular biologist; Stefano Mancuso, an Italian plant physiologist; František Baluška, a Slovak cell biologist; and Elizabeth Van Volkenburgh, an American plant biologist—who proposed a new field of inquiry controversially called “plant neurobiology.” Pollan wrote:
“Plants are able to sense and optimally respond to so many environmental variables—light, water, gravity, temperature, soil structure, nutrients, toxins, microbes, herbivores, chemical signals from other plants—that there may exist some brainlike information-processing system to integrate the data and coördinate a plant’s behavioral response. The authors pointed out that electrical and chemical signaling systems have been identified in plants which are homologous to those found in the nervous systems of animals. They also noted that neurotransmitters such as serotonin, dopamine, and glutamate have been found in plants, though their role remains unclear.
“Hence the need for plant neurobiology, a new field ‘aimed at understanding how plants perceive their circumstances and respond to environmental input in an integrated fashion.’ The article argued that plants exhibit intelligence, defined by the authors as “an intrinsic ability to process information from both abiotic and biotic stimuli that allows optimal decisions about future activities in a given environment.”
The Secret Life of Plants (distinct from the BBC Series The Private Life of Plants, also excellent) features a soundtrack by Stevie Wonder. Perhaps best of all, the film can be watched for free in its entirety online:
Jim and Jamie Dutcher are a filmmaking couple who, from 1990-1996, lived with a pack of wolves in the Sawtooth Mountains of Idaho. Although wolves have been characterized as bloodthirsty beasts and the bane of helpless livestock, the Emmy Award-winning filmmakers (Wolves at Our Door), spent six years in a tented camp to document just how misunderstood these animals are. Living with Wolves, released in 2005, is the continuation of the story begun with Wolves at Our Door. The Dutchers have since started a nonprofit, Living With Wolves, to help correct misconceptions about these intelligent, social animals and raise awareness about their importance to a healthy, functioning ecosystem. Their beautiful film can also be viewed for free below…But take a minute to make a donation to support their work!