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The Not-So-Secret Life of Plants Sigma Xi, The Scientific Research Society The Not-So-Secret Life of Plants: In which the historical and experimental myths about emotional communication between animal and vegetable are put to rest Author(s): Arthur W. Galston and Clifford L. Slayman Reviewed work(s): Source: American Scientist, Vol. 67, No. 3 (May-June 1979), pp. 337-344 Published by: Sigma Xi, The Scientific Research Society Stable URL: http://www.jstor.org/stable/27849226 . Accessed: 06/01/2013 17:37 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Sigma Xi, The Scientific Research Society is collaborating with JSTOR to digitize, preserve and extend access to American Scientist. http://www.jstor.org This content downloaded on Sun, 6 Jan 2013 17:37:06 PM All use subject to JSTOR Terms and Conditions Arthur W. Galston The Not-So-Secret Life of Plants Clifford L. Slayman In which the historical and experimental myths about emotional communication between animal and vegetable are put to rest In the troubled years of the late 1960s, Onto this scene, in 1973, burst a book, several book-club selections, made a wave of antiintellectualism swept The Secret Life ofPlants (1),which the book vastly popular. (Perhaps the success was through the United States, accom claimed formembers of the vegetable ultimate measure of its in panied by an antiscientism that still kingdom many mental capabilities the spate of cartoons it inspired the as to in persists in some measure. Some previously regarded limited New Yorker and the syndicated some public antipathy to the methods and gods, human beings, and higher strip Doonesbury.) Had the majority to products of science was understand animals. These included the ability of readers taken it in with the joy of able, because certain of the techno perceive and respond to human escape to fantasy that may be ac to a no logical applications of science had thoughts and emotions and distant corded good novel, damage failed to better man's condition and traumatic events, such as the injury would have been done. This was not indeed had perceptibly diminished or death of other organisms. Quoting what happened, however. The book ran the pleasure and grace of modern from uncontrolled experiments, catalyzed numerous claims of bizarre existence. Critics were quick to dom observations, and anecdotal re observations from "one-man" labo equate science with antihumanism, ports, the book fashioned a case for ratories; it led to a widespread lay and to call for reliance on alternate the ability of plants to count, to criticism of professional scientists for ways of arriving at an understanding communicate with each other, and to not taking account of the purported of the universe about us. This appeal receive signals from life forms else facts of plant existence; and it per were found receptive ears in a world wor where in the universe. Plants meated student arguments in uni ried about pollution, overpopulation, alleged to respond favorably to cer versity biology classes. unemployment, growing crime, tain forms of music (e.g. preferring and?perhaps most important?a Bach to rock); to display conditioned In response to this uncritical acclaim, nasty and persistent war in which reflexes; to predict storms, earth though perhaps after undue delay, even technology played a major role. quakes, and the like; and to several scientific reviews of the book transmute elements (in order to avoid appeared (2, 3, 4), and the American mineral starvation). Among the many Society of Plant Physiologists bizarre claims, the one that strains (ASPP) and the American Associa credibility the most is the assertion tion for the Advancement of Science that we can rid plants of insect pests, (AAAS) scheduled sessions to evalu or fertilize the soil inwhich they grow, ate some of the claims made. One of Arthur W. Galston is the Eaton Professor of simply by exposing photographs of the most tangible and also crucial Botany at Yale. He has been president of the the growing plants to particular portions of Tompkins and Bird's Botanical the American Society of America, frequencies of electromagnetic ra book is a discussion of electrophysi Society of Plant Physiologists, and the Society diation. Throughout, the book in ological experiments on plants con for Social Responsibility in Science. His re mixed accounts of ducted Cleve search concerns the action of light and hor discriminately by polygraph expert mones in plant development. A former Sigma generally accepted phenomena with Backster (5). In June 1974, at the Phi Beta Xi National Lecturer and Kappa unsubstantiated and incredible re ASPP meeting, Dr. B. G. Pickard of Visiting Scholar, he was the first American ports. Washington University organized a scientist to visit the of People's Republic at which China, in 1971. Clifford L. Slay man is an As symposium independent of the Peter were sociate Professor in the Department of Phys The authors book, and well-controlled experiments iology at the Yale School ofMedicine, where Tompkins and Christopher Bird, are, described (6) that had attempted? he has since 1967. With his Caro taught wife without question, adept popularizers but failed?to reproduce Backster's lyn, a geneticist, he has probed the chemical of scientific and technological topics results. Following this, Galston or and physical mechanisms leading to the gen and are with a session at the AAAS meet eration of electrical potentials in living cells. certainly acquainted ganized some re This article will appear as a chapter in Science aspects of modern plant ing in January 1975, which brought and the Paranormal, ed. G. O. Abell and B. search. Moreover, the issuance of the Backster face to face with some of his to be later this year by Singer, published book was shrewdly timed to take ad critics, including the two scientists, E. Charles Scribner's Sons. Address: Arthur W. vantage of the malaise about L. and J. M. Kmetz, who Galston, Department of Biology, 904 Kline general Gasteiger noted above. These to to Biology Tower, Yale University, New Haven, science facts, plus had gone great lengths repro CT 06520. a lavish advertising campaign and duce Backster's experimental condi 1979 May-June 337 This content downloaded on Sun, 6 Jan 2013 17:37:06 PM All use subject to JSTOR Terms and Conditions tions. Subsequent to this meeting, a swelling, etc.) of plant materials. With observed that differences of electric number of national television and these instruments he was able to potential measured along plant stems radio confrontations were organized, demonstrate withdrawal movements and roots (we shall return to the but these eventually ceased when of plant tissues from sites of injury, methodology of these measurements scientist participants realized that the complementing for "ordinary" plants below) were acutely sensitive to hoped-for dialogue was replaced by the much more conspicuous move metabolic poisons (15), while Lun unbending restatements of previous ments displayed by various insecti degaardh found that the same dif positions. vorous and photoperiodically sensi ferences of potential, along with the tive plants (e.g. Venus's-flytrap, rate of oxygen consumption by the Since it is on the interpretation of sundew, and Mimosa). He also de tissues, were closely tied to cellular electrophysiological data that Back scribed events in aquatic higher uptake of anions from the medium ster's case and much of the Tomp plants that resembled action poten (16). The inference was drawn that kins-Bird case rests, the purpose of tials (8), while other investigators, metabolism could "pump" charges, the present essay will be to reexamine following the lead of Burdon-San both ionic and electronic, through the the published experiments and to derson in 1873 (9), demonstrated ac cell surface membranes, thus creating relate them?from the point of view tion potentials (and in some cases an electric-potential difference across of both philosophy and technical simple integration) in insectivorous the membranes. This idea came to procedures?to the body of controlled plants, mechanosensitive plants, and fruition in the late 1960s, after P. and reproducible electrophysiological giant algae (10,11). Since Bose's time, Mitchell (17) realized that it could experiments that have been carried events similar to action potentials account for numerous experimental out on plants. have been described in a wide variety data on the movement of ions and of plant cells (12) and even in fungi trapping of energy by mitochondria Electrophysiology of (13). Bose quite properly pointed out and chloroplasts, the subcellular or similarities between the for plants functional ganelles responsible conserving electrical/mechanical responsiveness, energy from the oxidation of sugar It is commonplace knowledge, or irritability, of plant and animal and from the capture of light, re reaching back to Galvani (7) in the tissues, but his data do not in any way spectively. eighteenth century, that variations of support Tompkins and Bird's con electric potential are an essential clusion that plants perceive their en The primary charge separation giving feature in the function of specialized vironment in the manner of human rise to bioelectric potentials takes animal cells and tissues, manifest beings and other higher animals. place across the bounding surface most conspicuously in the transient membranes of individual living cells, electric signals, called action poten While Bose's thought was very ad whence comes the familiar piece of nerves tials, found in and muscles vanced in some respects, itwas rather jargon "membrane potential.,, after stimulation.
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