Reproduction
A thought experiment: If human reproduction is considered by analogy to plant reproduction, the very notion of reproduction is enlarged, estranged, and transformed in ways that can prove useful for rethinking some basic questions about reproduction.
The feature of plant reproduction that proves most terminologically dense and conceptually challenging is the alternation of generations. Plants alternate between two distinct life stages: a haploid sexual phase (gametophyte) and a diploid asexual phase (sporophyte). Unlike metamorphosis in insects, in which the movement from one life stage to another is linear, the gametophyte and sporophyte in plants alternate. The process is called “heterogenesis” or “metagenesis.” Both gametophyte and sporophyte are multicellular, and in algae, they generally exist as independent organisms. In bryophytes, that is, nonvascular land plants such as mosses, liverworts, and hornworts, the gametophyte is dominant, and the sporophyte depends on it. The reverse is true of vascular plants, where the sporophyte dominates, and the gametophyte is dependent. But if used categorically, these terms—“dependent” and “dominant”—are somewhat misleading, for each phase could also be said to be dependent on the other while remaining autonomous. Alternation can be described as an “intercoursing” of these stages or phases, which makes it difficult to draw firm boundaries around the where and how of reproduction.
In a lecture on “moss sex,” Catherine Kleier plays with an analogy between plant reproduction and human reproduction:
Animals don’t have a haploid life stage. The only haploid thing in animals is the sperm and the egg. And these things are not free living as whole generations for any animal. While we’re on the subject of the haploid phase, in bryophytes, it is actually the haploid phase of the gametophyte that is truly independent; while it is the diploid sporophyte that remains attached and dependent. This would be like me being dependent on my own egg![1]
Kleier’s humorous analogy summons a thought experiment full of possibilities utterly strange and eerily familiar. Imagine a large multicellular egg (or sperm) with tiny human bodies sprouting from it. The dominant egg organism would enjoy an autonomous existence and would reproduce sexually to generate the human body organism, but the latter would be able to reproduce itself asexually. Reproduction, then, is not neatly localized in discrete acts of procreation or sexual intercourse or in discrete zones of the body, for that matter. Reproduction is distributed within and across organisms, and sexuality is happening in many zones and across them.
Perhaps because it so radically challenges the tendency to localize sexual reproduction, the alternation of generations is often dismissed as an evolutionary remnant or dead end, overcome by later developments, and thus of passing importance. This tendency to impose a paradigm of progress on evolution is difficult to dislodge. Indeed, even as David George Haskell strives to correct the progressive view, he repeats it:
This notion of mosses as evolutionary leftovers fails on several counts. If mosses were backward hicks dying out in the face of superior modernity, we would expect to see fossil evidence of an early period of glory, followed by a slow descent into obscurity. But the scant fossil evidence shows the reverse. Further, fossils of the first primitive land plants bear scant resemblance to the carefully arranged leaflets and elaborate fruiting stalks of modern mosses. [ . . . ] Mosses have evolved their own way of being, a way that is not now, nor ever was, just a halfway house to a “higher” form. [ . . . ] Mosses work out of a different architectural textbook from that of trees, but the end result is arguably as complex and certainly as successful at long-term evolutionary survival. [ . . . ] Half a billion years of life on land have turned mosses into expert choreographers of water and chemistry.[2]
In his bid to establish that mosses are not evolutionary leftovers or remnants, even as he acknowledges that mosses were never a halfway house, Haskell also feels obliged to present them as being as modern, progressive, and developed as allegedly higher organisms.
A similar problem arises with the alternation of generations. Nothing in evolutionary theory gives credence to a developmentalist view in which some organisms can be characterized as “primitive,” in the sense of lesser or inferior, and yet vascular flowering plants are frequently characterized as modern, more highly evolved, more successful. By the same token, their mode of alternation, in which the sporophyte dominates, is deemed to present an advance over the dominance of the gametophyte in mosses and other bryophytes. Surely, however, the moss mode of alternation should not be considered as evolutionary leftover. All modes of alternation should be considered to be instances of what Haskell aptly dubs “choreographic expertise.” Yet a good deal of policing is done to maintain strict boundaries and to sustain hierarchies. One of the strictest is the divide between plants and animals. Animals are said to dispense with the alternation of generations in their evolution.
Still, the alternation of generations is such a prevalent feature that biologists have occasionally entertained the possibility of uncovering echoes or remnants of it in animals.[3]In the February 1905 edition of the Botanical Gazette, for instance, Charles J. Chamberlain presents an argument for “The Alternation of Generations in Animals from a Botanical Standpoint,” based on features observed during cellular mitosis in animals. The interest of Chamberlain’s account in this context lies less in its scientific merits (arguably thin by contemporary standards) than in the trouble that arises when analogies are drawn between plant reproduction and human reproduction. The analogy forces Chamberlain to consider the human body on the model of the vegetative body—as asexual. He balks: “It is strictly correct to speak of male and female gametophytes in plants; but in my opinion to designate the sporophyte as an asexual generation is a mistake. The sporophyte is male or female as truly as is the gametophyte.”[4]Chamberlain proposes to rule out asexual reproduction, and in a footnote, he banishes monoecism and hermaphroditism as well. These queer possibilities threaten his desire to delimit reproduction: Once the alternation of generations is introduced, reproduction cannot be localized and circumscribed, sexual reproduction cannot be held apart from asexual reproduction, and bodies cannot be ascribed a sex in a binary manner. Plants reveal reproduction to be simultaneously sexual and asexual, binary and nonbinary, and in a systematic manner. The two generations can be held apart to the point of becoming autonomous individuals (as in algae) and yet at the same time can be treated as phases of a single organism or individual. The two generations can equally well be said to generate and consummate each other, to produce and consume each other. The phases always arrive entangled, ontologically distinct yet not ontologically divided—intercoursing, so to speak.
One way to avoid the complexity of intercoursing is to do as Chamberlain does: explicitly ban the asexual and nonbinary from the scene of reproduction. Botany and evolutionary theory usually adopt a subtler strategy of avoidance, deploying paradigms of dominance and dependency in a manner that introduces hierarchies. Kleier’s jocular remark about moss sex is telling in this respect: “This would be like me being dependent on my own egg!” Even as she issues an invitation to imagine the weirdness of the situation, her understanding of dependency and autonomy is not unsettling at all. Her remark implies that humans are, in fact, normally independent of their egg or sperm; one would have to suspend reason to imagine things otherwise. Nothing, however, could be less obvious. Fields of inquiry as different as genetics and psychoanalysis dampen cheery assumptions about human independence. Richard Dawkins’s formulation of the selfish gene, for instance, casts the mind and body of organisms as secondary to the mission of genes to be fruitful and multiply.[5]As for the Freudian tradition, while it does not speak of genes or gametes per se, it acknowledges the importance of nonconscious drives, among them sexual drives. Finally, it is something of a truism in cultural and social theory that a woman may not be independent of her egg, at least not without a fight, as current battles in the US over reproductive rights attest. In sum, what Kleier proposes in good fun as an inversion of our commonsense understanding of ourselves turns out to be uncomfortably close to home.
Nevertheless, her proposition to estrange the commonsense understanding of human reproduction is worth pursuing as a thought experiment. When Kleier situates human bodies within the alternation of generations, they take the place of the sporophyte. This makes sense. With the emergence of seed plants or spermatophytes (gymnosperms and angiosperms), the sporophyte becomes dominant, and the gametophyte dependent. This situation feels familiar, in keeping with the commonsense view of human agency: A woman is not dependent on her egg. What proves startling, however, is the unexpected alignment of the human body with the vegetative body and thus with asexual reproduction and maybe even nonbinary sexes, which is where Chamberlain jumped ship.
The prolixity of pathways for asexual or vegetative reproduction in plants—budding; fragmenting or splitting; propagating from leaves, stems, or roots; and sporulating—has long been a source of fascination. Asexual reproduction reinforces an image of plants as veritable growth machines, propagating relentlessly, rampantly, extending every which way at once. Were it not for the beauty of flowers, sexual reproduction might not attract much attention in comparison with such extravagant modes of asexual proliferation. Indeed, this vegetative capacity sits at the origin of Western thought, in Aristotle’s philosophy of life.
Jeffrey Nealon offers this insightful gloss on Aristotle’s characterization of plants: a “nearly boundless growth-energy [that] is too powerful for these rudimentary organisms to control or canalize. Plants simply can’t control the pure immanence of growth that is their psukhe,” that is, their psyche or soul, which might be literally glossed as “psychic power.”[6]Nealon notes that, because Aristotle and Plato construed plants as lacking an end-form or ideal entelechy, they considered them to be merely living growing matter. Nonetheless, even though plants have only this power of nutritive growth at their disposal, that power is, for Aristotle, the power of life itself. Nealon explains that “no life-forms can exist without the nutritive psukheof plants, and concomitantly all living things necessarily deploy a dose of the nutritive or vegetable soul, what Aristotle calls ‘the originative power, the possession of which leads us to speak of things as living at all.’”[7]
Giving ontological priority to the vegetative body of plants, Aristotle also grants, in effect, priority to asexual reproduction. Here it is difficult not to wonder: Were originative asexuality acknowledged as such and situated at the origin of Western philosophy, would we read the history of modern sexuality quite differently?[8]Nonetheless, granting primordial power to the vegetative or nutritive soul of plants can also become a way of avoiding the thought experiment afforded by plant reproduction, if it avoids the intercoursing of the asexual and the sexual. The problem is not Aristotle’s alone. Evolutionary theory and botanical sciences have long vacillated on whether to grant ontological priority to asexual or sexual reproduction. Indeed, in some branches of evolutionary science, the prevalence of sexual reproduction is considered paradoxical from the standpoint of fitness advantage. After all, sexual reproduction does not necessarily produce variability in offspring, while the costs in terms of time and energy are substantial, among them the search for a willing mate.[9] Faced with this prospect, other evolutionary scientists feel compelled to speak up for sexual reproduction, to defend its cause. Today, arguments for the necessity, priority, and even superiority of sexual reproduction seem to carry greater weight. Nonetheless, the underlying and ongoing vacillation between granting priority to asexual or sexual processes remains worthy of careful attention because it is indicative of a divide between two ways of thinking about reproduction.
A legacy that might be characterized as Aristotelian places emphasis on iteration or repetition, granting primordial status to asexual nutritive reproduction. Another line of thinking that might be characterized as Darwinian or evolutionary gives primacy to variation, usually privileging sexual reproduction. This is precisely where the intercoursing of asexual and sexual reproduction in plants issues its challenge. Efforts are consistently made to situate the power of life on one side or the other, as variation or iteration, and yet the alternation of generations in plants makes it impossible to locate reproduction definitively in the one or the other. Troubled by the possibility of an intercoursing of asexual and sexual reproduction, descriptions of plant reproduction typically resort to rhetorical gestures and qualitative evaluations that at once evoke and bury the disturbing entanglement. Take this description from the Biology Dictionary: “The alternation of generations allows for both the dynamic and volatile act of sexual reproduction and the steady and consistent act of asexual reproduction. When the sporophyte creates spores, the cells undergo meiosis, which allows the gametophyte generation to recombine the genetics present.”[10] The Biology Dictionarydoes not resolutely opt for one side or the other; instead, it introduces a qualitative appraisal: Asexual reproduction is steady and consistent, while sexual reproduction is wild and volatile.
This shift to qualitative and affective ways of managing the trouble engendered by plant reproduction allows for the formulation of a couple of hypotheses issuing from this thought experiment. First, because it becomes impossible to hold apart the iteration inherent in Aristotle’s nutritive soul and the variation required of Darwin’s natural selection, other “affective” concerns swarm into the intercoursing field of reproduction. The Freudian approach, for instance, suggests that an individual can be steady and wild, or consistent and volatile, or iterative and variant, at one and the same time, or in irrational series. As such, if formulations such as “plants are like people” and “plants have agency” are taken seriously, plants should not be deemed in advance to be less troubled and uncertain than humans, even if their troubles are of a different order. By the same token, human sexuality and reproduction may not be any more “naturally” categorized and localized as sexual or asexual, as binary or nonbinary, than plant reproduction and sexuality are.
Second, the trouble arising around plant reproduction invites a hypothesis about “Why plants, why now?” Plant philosophers and theorists often speak in terms of overcoming the exclusion or “othering” of plants within the Western intellectual tradition.[11]Nealon challenges this line of reasoning, not only returning to Aristotle’s plant psyche but also turning to Foucault’s explanation for the intensified interest in animals within the biopolitical era: “Biopolitics remains invested in animals not because animals constitute our ‘others’ but because animality provides the subtending notion of subjective desire that gives rise to biopower in the first place.”[12]Animality gives rise to a subjective apparatus in which living is “understood as evolving, appetite-driven, secret, discontinuous, mendacious, inscrutable, always on the prowl, looking for an opening to break free.”[13]From the standpoint of plant reproduction, this biopolitical animality would fall on the side of the wild and volatile variation associated with sexual reproduction. The biopolitical impulse behind “vegetality” (the intensified interest in plants) may not be to break resolutely with animality but to mitigate and complicate it, inflecting the subtending biopolitical norms of subjective desire by asexualizing and queering them. From the standpoint of the intercoursing of plant reproduction, then, queering might be considered sexually nonnormative yet biopolitically norming.[14]
Notes
[1] Catherine Kleier, “Lecture 3: Moss Sex and Peat’s Engineered Habitat,” in Plant Science: An Introduction to Botany; this passage was transcribed from Lecture 3, published with the Great Courses series of audiobooks.
[2] David George Haskell,The Forest Unseen: A Year’s Watch in Nature, “February 16—Moss,” passim.
[3] A classic example comes from honeybees whose drones are haploid males. Although it is no longer common to think this example alongside the alternation of generations in plants, it is worth noting that the physicist Erwin Schrodinger makes this association in his lectures on physics and life, in What is Life?The Physical Aspect of the Living Cell (Cambridge University Press, 1992), 24–25.
[4] Charles J. Chamberlain, “The Alternation of Generations in Animals from a Botanical Standpoint,” Botanical Gazette(February 1905), 143.
[5] Richard Dawkins, The Selfish Gene, 40th anniversary edition (Oxford University Press, 2016).
[6] Jeffrey T. Nealon, Plant Theory: Biopower and Vegetable Life (Stanford University Press, 2020), 32; 35.
[7] Nealon, Plant Theory, 35, citing Aristotle (DA 413b1).
[8] Such a gesture may not be incompatible with Foucault’s genealogical turn, in his history of sexuality, toward techniques de soi, that is, practices or techniques of self, which might be situated at the site of entanglement of the asexual and the sexual.
[9] S. P. Otto and T. Lenormand, “Resolving the Paradox of Sex and Recombination,” Nature Reviews Genetics 3 (2002): 252–61.
[10] Biology Dictionary editors, “Alternation of Generations,” Biology Dictionary, last updated May 17, 2018, https://biologydictionary.net/alternation-of-generations/#:~:text=The%20alternation%20of%20generations%20allows,to%20recombine%20the%20genetics%20present.
[11] Two key books on plant philosophy make powerful statements to this effect. See Emanuele Coccia, The Life of Plants: A Metaphysics of Mixture (John Wiley & Sons, 2019) and Michael Marder’s Plant-Thinking: A Philosophy of Vegetal Life (Columbia University Press, 2013).
[12] Nealon, Plant Theory, x.
[13] Nealon, Plant Theory, 8.
[14] Robyn Wiegman and Elizabeth Wilson’s rethinking of the antinormative politics of queer theory by reference to Henri Canguilhem’s account of norms is one source for this line of thinking. See Robyn Wiegman and Elizabeth A. Wilson, “Introduction: Antinormativity’s Queer Conventions,” differences 26, no. 1 (2015): 1–25.