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Sense and sentient ability


By Sue Burke

TOR: 2018. 336 PP. £15.00

Semiosis is the use of signs or symbols to convey meaning. These symbols can be any form of visual, auditory, olfactory or tactile communication. The word semiosis also resembles symbiosis, a close ecological association between two species, which can range from mutually beneficial to exploitation of one species by another. Though never explicitly defined, both concepts form a central theme in Sue Burke’s Semiosis, which explores the relationships between humans newly arrived on the planet of Pax and the sentient plant species they encounter there.

In my lectures on species interactions while teaching introductory biology, I often pose the following question to my students: under what environmental conditions will a positive symbiotic relationship become exploitative? In other words, when does mutualism become parasitism? The responses often relate to nutrient abundance, the prevalence of predation or herbivory, and other stressors. Semiosis pushes this question further by adding self-awareness and sentience to the dynamic, allowing for the possibilities of manipulation and deceit, altruism and compassion, trust and suspicion, on both sides of the relationship. One individual defines mutualism as “mutual control” (p274), and each species struggles with sharing control and trusting their mutualists to not overexert their control. “Mutualism can be coerced,” states one individual, highlighting this dualism: “Civilization can be imposed” (p244).

Read wholly, Semiosis feels like a hopeful story — multiple sentient species finding ways to work together for the common good. Even when diplomacy falls apart and cultural differences lead to hatred and suspicion, the species are linked by their similarities; for example, by their mutual love of beauty in its varied forms of art, architecture and music; and by their shared emotions of love, grief and even selfishness. In their own way, each species struggles with the continued influence of their pasts, and with the choices they must make for the future: to choose mutualism or individualism.

Still, Semiosis leaves the reader wanting more. Numerous characters hint at mysteries that are never revisited or resolved. We see suggestions of violent histories in numerous species on Pax; what sorts of symbioses existed before human arrival, and how mutualistic or exploitative were they? We see the knowledge that the first generation of humans on Pax failed to share with future generations; was this knowledge lost accidentally, or was it an intentional oversight by the early inhabitants to control the perspective of future generations and influence their behaviour? Why was the Rainbow City abandoned by its first inhabitants? And what inspired the humans’ fear of it? Above all, what events on Earth led to a 158-year exodus to Pax?

Additionally, the relationships between the species suggest commentary on human behaviour that, if intended, is never fully explored. A faction of the humans exhibits deep-seated fear and suspicion of their closest mutualist species, frequently questioning the other’s ability to control or influence human behaviour. Another species shows overt violence towards its own members, including an aggressively enforced caste system. One species takes over an abandoned city, and when its past inhabitants petition for their own return, a faction argues the original inhabitants “don’t belong here” (p317). One species attempts to ‘impose civilization’ on another sentient species by being “aggressively friendly” (p272), and invites these individuals into their society while still excluding them from participating in governance. One species refers to another as “stinking, stupid savages” (p217). Are these intended as a commentary on racism and bigotry in America, and the general subjugation, marginalization and ‘coercion of civilization’ on numerous groups throughout the world’s history? If so, they are not pushed far enough to force the reader to see the parallels on Earth. The author intends a sequel (perhaps even a series), so maybe these issues will be reconsidered in subsequent books; however, their oversight here weakens the strength of Semiosis as a stand-alone text.

Similarly, the ecology of Pax and the portrayal of sentient non-human species (especially plants) leaves something to be desired, particularly for a scientific audience. With a few exceptions, the biology of Pax organisms is rather terran — likely intentionally so, as the author has stated that Semiosis was inspired by her study of plant behaviour on Earth. Most organisms are even named after terran groups, such as cactus, tulip, pineapple, bamboo, coral, eagle, moth and so on. These factors make the biology of Pax organisms feel less imaginative and their abilities beyond that of terran organisms feel less realistic to a scientific reader (particularly a plant biologist) than to a lay audience. This is a delicate balance for a science fiction author to navigate: the desire to make the fictional planet’s species similar enough to Earth’s that the reader can identify with them, but different enough that they feel unique and imaginative. This is an even harder balance to navigate for an audience of biologists. Despite its presentation as a botanical story, the novel is very human-centric, and even the non-human sentient species feel very human in their thoughts and behaviour. As is often the case in this genre, the ecology of Pax is a literal and figurative backdrop against which human (or human-like) society blends or contrasts. Perhaps throughout the series, Pax organisms may more fully illustrate their unique biology; however, in Semiosis, a scientific reader will struggle with the obvious similarities between life on Pax and Earth, and the seemingly preposterous abilities of Pax’s plant life compared to their terran equivalents.

Equally preposterous is the behaviour of some of Pax’s human residents, particularly the scientists. In repeated instances, the humans leap to incredible conclusions, taking single observations and extremely limited information to be irrefutable evidence of sentience, semiosis, savagery, deceit or manipulation in another species. This is most frustrating in the colonist’s first botanist, who identifies the first plant that can “think and plan ahead” and has “decided to kill us in every way it could and had invented tactics to do it” (p37) on the slimmest of forensic and biological evidence. Arguably, the botanist would, in reality, be the least likely person to believe this on such paltry data, and yet he says “I knew [the plant] had killed us deliberately, with malice and forethought, but that was too hard for anyone else to believe” (p39). This portrayal is likely to alienate a scientific reader even further than the treatment of Pax’s ecology.

Despite these drawbacks, a plant biologist can enjoy Semiosis, particularly if one is capable of suspending disbelief on developmental capabilities in plants. Hopefully subsequent novels on Pax will answer many of the questions Semiosis raised, and allow the reader to more fully explore the unique ecology of Pax and the evolution of mutualism between its sentient species. “I’d have a long chapter to write about [these events],” one character says, “Yet it wouldn’t be the last chapter. Or the longest” (p333). I look forward to those chapters one day.

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Correspondence to Laci Gerhart.

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Gerhart, L. Sense and sentient ability. Nature Plants 4, 235–236 (2018).

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