Plant intelligence
[2][3] Plant intelligence has been defined as "any type of intentional and flexible behavior that is beneficial and enables the organism to achieve its goal".
[13][14] He has been cited as an early botanist "attracted to the notion that the ability of plants to feel pain or pleasure demonstrated the universal beneficence of a Creator".
"[23] One visitor to his laboratory, the vegetarian playwright George Bernard Shaw, was intensely disturbed upon witnessing a demonstration in which a cabbage had "convulsions" as it boiled to death.
Historian Ed Folsom described it as "an exhaustive investigation of how such animals as bees, ants, worms and buzzards, as well as all kinds of plants, display intelligence and thus have souls".
[33] In the 1960s Cleve Backster, an interrogation specialist with the CIA, conducted research that led him to believe that plants can feel and respond to emotions and intents from other organisms including humans.
Backster's interest in the subject began in February 1966 when he tried to measure the rate at which water rises from a philodendron's root into its leaves.
Backster stated that, to his immense surprise, "the tracing began to show a pattern typical of the response you get when you subject a human to emotional stimulation of short duration".
[35][36] In 1975, K. A. Horowitz, D. C. Lewis and E. L. Gasteiger published an article in Science giving their results when repeating one of Backster's effects – plant response to the killing of brine shrimp in boiling water.
[38][39][40][41] Botanist Arthur Galston and physiologist Clifford L. Slayman who investigated Backster's claims wrote: There is no objective scientific evidence for the existence of such complex behaviour in plants.
Unfortunately, when scientists in the discipline of plant physiology attempted to repeat the experiments, using either identical or improved equipment, the results were uniformly negative.
[37][43] Whilst the book captured public attention it severely damaged the credibility of the field of plant intelligence.
Philosopher Yogi H. Hendlin noted that the book's "combination of haphazard, panpsychist metaphysical speculations and unmethodical citizen science stigmatised legitimate progressive plant research, alongside the era’s new-age pseudoscience, tarring the discipline’s serious inquiry".
[45] In the book Retallack records experiments she conducted at Temple Buell College on applying different music to plants.
[51] In 2012, Paco Calvo Garzón and Fred Keijzer speculated that plants exhibited structures equivalent to (1) action potentials (2) neurotransmitters and (3) synapses.
Also, they stated that a large part of plant activity takes place underground, and that the notion of a 'root brain' was first mooted by Charles Darwin in 1880.
'[52] In 2017 biologists from University of Birmingham announced that they found a "decision-making center" in the root tip of dormant Arabidopsis seeds.
In 2017 Yokawa, K. et al. found that, when exposed to anesthetics, a number of plants lost both their autonomous and touch-induced movements.
Venus flytraps no longer generate electrical signals and their traps remain open when trigger hairs were touched, and growing pea tendrils stopped their autonomous movements and were immobilized in a curled shape.
Raja later stated that "If the movement of plants is controlled and affected by objects in their vicinity, then we are talking about more complex behaviours (rather than simple) reactions".
[64] The book was widely criticized by biologists and forest scientists for using strong anthropomorphic and teleological language such as describing trees as having friendships and registering fear, love and pain.
[61] The model has been criticized for being based on only speculation and lacking empirical evidence for its claim that cells have consciousness.
