Entangled Life: How Fungi Make Our Worlds, Change Our Minds & Shape Our Futures

The title of Chapter 3, “The Intimacy of Strangers,” shows how Sheldrake anthropomorphizes his subject matter to paint a vivid picture of fungal behavior. The “strangers” in this case are not other people but the fungi that predate and possibly affected their evolution—calling their proximity to human life “intimacy” underscores how crucial fungi are to the world in which we live and how little about them we still know.

Like in other chapters, Sheldrake combines scientific history, cutting-edge experiments, and his own experiences to tell the story of lichen. He writes about his yearly trips to the coast of British Columbia in small sailboat, which his friends and he struggle to navigate through the choppy waters along the rough, rocky coastline. By showing how harsh the environment is from a human perspective, he conveys why it is so surprising that many species of lichen live there. Sheldrake has spent hours engrossed in looking at these organisms, some alive and some dead, some existing peacefully while others compete, encrusting nearly all of the rock found on earth.

Ultimately, “The Intimacy of Strangers” becomes an exploration of scale and of what it means to be an individual organism. Lichen species are treated as individual organisms, but in reality each lichen is a tiny ecosystem made up of at least one fungus and one alga, and sometimes many other types of microbial life. The exact makeup of these beings and the ways they interact can cause immense changes to the physical appearance and lifestyle of the lichen. Sheldrake sees this as a microcosm of life on earth. In most schools of thought, individual organisms are seen as discrete islands that interact but are inherently separate from each other. Lichens are just one type of fungal relationship to challenge this notion. They were the first organism to teach people about symbiosis. They were also one of the first organisms on earth, and continue to be the one most capable of surviving in extreme environments. To Sheldrake and other researchers, this suggests that lichen’s biological structure is not the exception in a sea of discrete individuals but a rule that can likely be applied to other organisms, ecosystems, and possibly the entire planet. Lynn Margulis, whose work is outlined throughout Entangled Life, first proposed a large-scale version of this idea. What she called the Gaia hypothesis states that the entire biosphere of the Earth works as one single, integrated system. There are no real individuals, and no real examples of nonsymbiotic life. Sheldrake places this idea alongside evolutionary biologist Richard Dawkins’s concept of extended phenotypes, which suggests that an organism’s phenotype comprises not only its own body but also outside structures that the organism depends on for survival. Although Dawkins is careful to construct a set of rules to prevent phenotypes from extending too far, Sheldrake believes that there is no real reason to limit them, other than to conform to human ideas of individualism. Instead, he believes that all organisms behave basically like lichen and that nothing would exist without its relationships to other organisms.

Chapter 4 outlines the ways that fungi can influence animal and insect behavior and thought. The millions of fungal species likely influence creatures in some way, so Sheldrake chooses to focus on two extremes of fungal mind control: cordyceps and psilocybin. He approaches the discussion of each organism differently. In the case of psilocybin, the book takes a more historical and theoretical approach, outlining the use of psychedelic mushrooms throughout history, their introduction to the modern Western world in the 1950s, their illegalization in most countries during the mid-20th century, and the ways that they are used in contemporary clinical research. Sheldrake explains that while psilocybin is one of the fungi that humans have interacted with most, there is little scientific knowledge about the mechanisms for, or the reasons behind, the fungi’s mind-altering properties. He offers a number of speculations that he readily admits have no known scientific basis. For example, some people believe psychedelic mushrooms are intentionally attempting to teach humans to appreciate the natural world. He doubts this hypothesis, since psilocybin evolved well before humans began to destroy the environment. This type of thinking intrigues Sheldrake, however, and he believes that it may speak to psilocybin’s purpose. When writing about cordyceps, Sheldrake takes a more strictly biological approach. He explains the mechanisms by which these fungi control insects and a number of experiments that have shown the exact biological processes they use to do this. The book touches on the fact that cordyceps fungi do not directly invade the insects’ brains but does not expand on what this means about the differences between psilocybin, which has a temporary but profound effect on brain function, and cordyceps, which is described as using a more physical approach to control its hosts.