Research team including Göttingen University reviews popular books on forests and criticises lack of scientific evidence
Popular science books are all the rage. Their aim is to convey scientific topics to interested members of the general public as clearly and entertainingly as possible. To succeed, authors describe the science using accessible language and concepts that will be interesting to their audience. For example, human attributes have been assigned to plants. Trees are said to experience feelings and care for their offspring like mothers do for their children. An international research team led by the Universities of Heidelberg, Göttingen and Umeå (Sweden) has now tested such descriptions against scientific evidence. The 32 researchers from eleven countries analysed statements from two popular books on the subject of forests. They conclude that metaphoric descriptions are often held as literally true, and warn against portraying plants as if they were like human beings. The results have been published in the journal Trends in Plant Science.
The researchers focused on the books "The Secret Life of Trees" by Peter Wohlleben and "Finding the Mother Tree" by Suzanne Simard. In these books, human characteristics and behaviours are attributed to trees - for example, the ability to feel pain and happiness, to communicate with each other or to act altruistically. "For both books, we were able to provide detailed proof, based on the scientific literature, that these key messages are scientifically untenable," explains Professor Christian Ammer from the Faculty of Forest Sciences and Forest Ecology at the University of Göttingen. "For example, the claim that trees try to avoid the loss of other members of that species by helping each other is clearly refuted by numerous research papers on the importance of competition between individuals of the same species." The "mother tree" concept, meaning the supposed targeted transfer of carbon from older to younger trees via networking fungi, is also not objective from the researchers’ perspective. Professor Andrea Polle from the same faculty says: "Many publications on which the concept is based are misinterpreted because in most cases where carbon transfer was observed, the role of fungal networks remained unknown. Further, the amount of carbon exchanged is in almost all cases so small that it is physiologically irrelevant for the receiving tree."
The researchers also criticise the fact that both books use sources as evidence that have not undergone the standard peer review process that ensures quality and scientific rigour. They call for a clear distinction between non-fiction and fiction by publishers. And they highlight the consequences: "It would be disastrous for the adaptation of forests to climate change if political decisions were made on the basis of pleasant-sounding, but incorrect messages, rather than on the basis of scientific fact," says Ammer.
Researchers in biology, ecology, microbiology and forestry from Chile, Germany, Great Britain, Ireland, Israel, Canada, Austria, Sweden, Switzerland, Spain and the USA participated in the project.
Original publication: D. G. Robinson, C. Ammer, A. Polle et al.: Mother trees, altruistic fungi, and the perils of plant personification. Trends in Plant Science (2023). 10.1016/j.tplants.2023.08.010
Professor Andrea Polle
University of Göttingen
Forest Botany and Tree Physiology
Büsgenweg 2, 37077 Göttingen
Professor Christian Ammer
University of Göttingen
Faculty of Forest Sciences and Forest Ecology
Silviculture and Forest Ecology of the Temperate Zones
Büsgenweg 1, 37077 Göttingen
Telephone: 0551 39-23671