The Form Is Never Final

Abstract

This essay argues that the human form is not final: natural selection continues in a second-degree, technogenic natural environment that the species manufactures. Understanding “form” as an integrated configuration (body, cognitive and relational dispositions, technical-symbolic couplings), it is shown how the shift of risk from early mortality to effective reproductive fitness reparameterizes evolution. In the technogenic niche, the informational mediation of encounter (metric proximity, algorithmic catalog-hierarchization-filter) favors assortativity and quantile matching; functional externalization redistributes cognitive costs; and mental health operates as a selective channel, from the extreme cutoff to chronic friction that postpones parenthood. A verification program is proposed with comparable indicators (nulliparity, age at first child, assortativity coefficients, prevalence of sexual inactivity), arguing that data function as philosophical operators that make capillary selection measurable. It is concluded that, by reconfiguring the environment, we reconfigure the pressures that shape us: the evolutionary future of the human is the multi-generational result of the ecologies we build.

Keywords: second-degree natural environment; capillary selection; effective reproductive fitness; metric proximity; quantile matching; functional externalization.

Initial Delimitation

What we call the human form — corporal, psychic, relational, and technical-symbolic — is neither a static given nor a teleological endpoint. It is a local functional stability of the species, always negotiated with the environment. In this essay, the focus is on the evolutionary dynamics of the species under 2nd-order selective forces — technically mediated forces that integrate the continuity of the natural. Here, "form" designates the integrated configuration of body, neurocognitive and affective processes, relational patterns, and technical-symbolic couplings that sustain reproduction and common life. Digressions about "incompleteness" in general or about ethical-political implications are avoided: the issue here is to describe, with material precision, how certain mechanisms of matching, effective reproductive fitness, and technical mediation reparameterize the evolution of the species. These dimensions are not compartments, but reciprocal couplings: variations in the body reorganize the psychic and relational circuit; alterations in technical-symbolic mediation reparameterize cognitive dispositions and patterns of encounter.

It is important here to distinguish two environmental regimes: the first-degree natural environment — physical-biological — in which the species was configured throughout most of its evolutionary history, and the second-degree natural environment — the technogenic one — which progressively thickens and today co-determines living conditions. It is not an “outside” of nature, but a layer manufactured by us, with its own rhythms, signals, and accesses that rewrite opportunities for matching and care, demanding new forms of attention, coordination, and maintenance.

We call this technogenic environment a second-degree natural environment — and not “artificial” — because it remains entirely within the material order: it is produced by natural agents (us), operates by the same physical, chemical, and biological causalities, and maintains the requirements of selection intact (variation, inheritance, and differential reproduction). What changes is not the principle, but the configurations: new gradients of risk, access, and matching. Therefore, natural selection continues to occur, now upon manufactured conditions that co-evolve with us.

This interpretation finds support in contemporary lines of research: Leroi-Gourhan (1964; 1965) on technical exteriorization and gesture-language coupling; Simondon (1958; 1989) on technical individuation and “associated milieus”; the vehicular externalism of Clark and Chalmers (1998) and Malafouris’s Material Engagement Theory (2013), which treat cognition as a body-thing-sign system; and, on the evolutionary level, niche construction (Odling-Smee, Laland, and Feldman 2003; Laland 2016) and gene–culture coevolution (Richerson and Boyd 2005). All converge on the idea that technology integrates the continuity of the natural and reconfigures the conditions of selection.

The Non-Finality of the Human Form

By manufacturing its own environment today, the species alters the pressures that select it. The development of a global technogenic niche reconfigures the selective landscape: the force of selection shifts primarily from early mortality to differences in effective reproductive fitness — that is, to variations in probability, timing, and number of viable offspring. This shift explains why we place differential reproduction at the center: in evolution, differences that do not translate into viable offspring die with the individual. Only when variation, inheritance, and differential reproduction converge does selection alter distributions (biological and symbolic-technical) across generations. It is, therefore, in how one matches, when one matches, and with whom one matches that a large part of the species' evolutionary destiny is decided today.

This non-finality has solid support both in the philosophy of biology and in contemporary biology. On the philosophical level, processual proposals (Dupré and Nicholson 2018) reject the idea of fixed forms and view living beings as open processes, continuously maintained and transformed by material and informational flows. On the empirical level, population genomics identifies extensive signs of recent and continued selection in humans (Akey 2009; Hawks et al. 2007), while demographic and longitudinal studies show ongoing selection in contemporary populations: direct estimates in cohorts like Framingham (Byars et al. 2010), evidence of microevolutionary change in ages at first child in a historical context (Milot et al. 2011), and relationships between reproductive patterns and polygenic profiles (Beauchamp 2016; Kong et al. 2017). Together, these lines support that human evolution continues, without teleology, and that the “form” — understood here as an integrated configuration — remains open to the selective reconfigurations imposed by an increasingly technogenic environment.

The ‘form’ in this essay is more than morphology: it includes cognitive and relational dispositions that emerge from material couplings with the environment and with artifacts.

2nd-Order Forces and the Technogenic Niche

Before mapping these forces, it is important to register a historical break: the species has not always systematically manufactured its environment. For most of its evolutionary history, the relevant environment was primarily first-degree. The regular manufacturing of the environment by the species itself intensified with agriculture and sedentarization (cycle control, storage, division of labor) and then accelerated with industry and modern technical networks. It is this process that prepares the second-degree natural environment in which contemporary selective pressures operate. In this key, the demographic transition (Omran 1971) and niche construction interpretations help clarify that selection has not stopped: it reconfigured itself as the environment also became manufactured.

Technology is not external to life: it is a secondary level of the natural, a material continuity that co-determines the environment. In this light, we can distinguish four families of forces that, together, reparameterize the costs and benefits of survival and reproduction.

Biotechnical forces include vaccination, advanced obstetrics and neonatology, assisted reproduction, and genetic screening/editing. Their clearest effect was to drastically reduce pre-reproductive mortality, shifting selection to traits that favor matching and parental care and altering reproductive ages and trajectories. This is the classic terrain of evolutionary medicine (Nesse 2010; Stearns 1999) and recent population genomics, where ongoing selection is estimated even in contexts with strong medical intervention; the demographic transition (Omran 1971) precisely describes this shift in risks that reparameterizes fitness.

Technoecological forces derive from urbanization, chronic pollutants, controlled microenvironments, and climate changes of anthropic origin. They produce low-intensity, persistent pressures that demand distinct immunoendocrine and metabolic coordination and decouple physical effort from survival, favoring profiles capable of persisting in materially complex environments. Concepts like exposome (Wild 2005) and urban metabolism (Wolman 1965; Bettencourt 2013) help name this web of artificial exposures and flows that compose the second degree of the environment; the planetary health agenda (Whitmee et al. 2015) shows how these manufactured conditions return as biological constraints.

Infosymbolic forces directly impact encounter: matching platforms and algorithmic catalog-hierarchization-filter systems convert physical proximity into metric proximity. The apparent abundance of options, imagistic idealization, and niche segmentation raise acceptance thresholds, generating choice overload and amplified assortativity. The typical result is a thickening of intra-quantile pairings (by education/status, by signs of attractiveness, by height), with effects on the timing and stability of reproductive bonds. Here, cultural evolution (Henrich 2016) provides the framework for understanding learning biases and preferences; studies on online matching and homogamy (Rosenfeld, Thomas, and Hausen 2019; Kalmijn 1998; Schwartz 2013) show how filters amplify homophily; and the literature on choice overload (Iyengar and Lepper 2000) helps interpret postponement and indecision as products of saturated catalogs and permanent algorithmic hierarchizations.

In the infosymbolic family, language and image function as signaling and screening operators: discursive and imagistic patterns stabilized by recommendation algorithms modulate attention, expectation, and acceptance. By converting preferences into comparable signals, the semiotic ecology of encounter reconfigures search costs, raises acceptance thresholds, and thickens assortativity, without breaking the material continuity of the process.

Cyborg forces encompass prosthetics, implants, psychopharmaceuticals, brain-machine interfaces (BCI), and exoskeletons. They create performance differentials that translate into indirect effects on income, social network, and longevity, influencing reproductive contribution throughout life. The philosophy of mind and technology has a precise formulation here: Natural-Born Cyborgs (Clark 2003) and Simondon's technical individuation describe these couplings as stable operative extensions, not as accessories; research in BCI and neuroprosthetics shows how such extensions can crystallize new functional margins.

How the Manufactured Environment Translates into Selection

With the drop in infant and juvenile mortality, selection acts primarily in the adult phase (Omran 1971). In operational terms, this shifts the relevant variation to traits that affect who manages to form reproductive pairs, when they do so, and with what stability — exactly what evolutionary demography has sought to measure through constraints on fertility and survival schedules.

In other words: selection now increasingly focuses on the capacity to operate in the second-degree natural environment. On average, profiles with greater resistance to stress, tolerance for social pressures, and competence for sustained cognitive effort tend to persist — that is, those who can maintain profiles capable of sustaining divided attention, working memory, and decision-making under permanent comparison, without operational breakdown. In parallel, robust affective regulation is required in the face of evaluation anxieties and social comparison scales which, when persistent, degrade the margin of self-modulation and reduce effective reproductive fitness. What changes, in depth, is the structure of matching: from local encounter we move to encounter by measured affinities. Online encounter displaces traditional intermediaries and becomes the dominant way of meeting (Rosenfeld, Thomas, and Hausen 2019), while revealing hierarchies of desirability and strong response gradients, with a sharp drop in the probability of message return as the distance increases in the algorithmic hierarchization between pursuer and pursued (Bruch and Newman 2018). In saturated catalogs, choice overload and permanent algorithmic comparison raise acceptance thresholds and favor postponement (Iyengar and Lepper 2000).

This results in a tendency for quantile matching, which increases the covariance between traits in couples and stratifies the distribution of resources and cultural capital in offspring. In terms of quantitative genetics, phenotypic assortativity increases additive variance and reinforces intergenerational similarities (Lynch and Walsh 1998). However, recombination and regression to the mean function as statistical brakes in the short and medium term, maintaining porosity between subpopulations (Lynch and Walsh 1998). Hence the image of a reproductive archipelago: panmixia is diluted into global sub-networks with soft barriers to gene flow, without implying speciation.

The functional externalization of memory, orientation, and coordination outside the biosome reorients the costs of what the body needs to maintain internally and shifts capabilities to artifacts, routines, and coordinated environments — this is the lesson of distributed cognition (Hutchins 1995) and cognitive artifacts (Norman 1991), compatible with vehicular externalism (Clark and Chalmers 1998). These technical-symbolic couplings are not accessories: they condition performance, support networks, and, consequently, reproductive trajectories.

Mental health functions here as a decisive channel on two levels: at the extreme cutoff, suicide implies zero fitness; in chronic friction, persistent depression reduces the probability of conception and delays the first child, with recent findings in couple samples and population registers (Liao 2024; Golovina 2023). These are capillary, cumulative effects, without moral teleology, but with measurable evolutionary impact if they persist over time.

Empirical Anchors and Verification Horizon

The recent empirical framework reinforces the interpretation that the manufactured environment reconfigures effective reproductive fitness through capillary pathways. In highly digitized populations, consistent increases in sexual inactivity and reproductive postponement have been observed. In the US, sexual inactivity grew between 2000 and 2018, especially among men aged 18–24 and 25–34, with about one in three men aged 18–24 having no sexual activity in the last year (Ueda et al. 2020), converging with the drop in sexual frequency documented in GSS series (Twenge, Sherman, and Wells 2017). In Japan, successive analyses of the National Fertility Survey show high and increasing levels of sexual inexperience among 18–39 year olds, and, among never-married 18–34 year olds, more than 40% without heterosexual experience in 2015 (Ghaznavi et al. 2019); the 2021 round confirms objective obstacles to encounter and a drop in marriage (NIPSSR 2022). These patterns are compatible with the displacement of intermediaries and the dominance of online encounter (Rosenfeld, Thomas, and Hausen 2019), suggesting that metric proximity and filters reinforce postponement and assortativity.

Mental health emerges as a measurable selective channel. In cohorts of couples in the general population, preconception depression is associated with a longer time to conception and a higher risk of infertility (Liao et al. 2024). In national registers, depression treated in secondary care is associated with a lower probability of having children and lower total fertility, with differences by sex and socioeconomic status (Golovina et al. 2023); similar results appear when modeling own depression, partner's depression, and childlessness (Kailaheimo-Lönnqvist et al. 2024). These findings do not establish fatalism; they merely indicate chronic frictions with reproductive effects when they persist.

Thus, the thesis is verifiable by a program of comparable indicators and series: — Nulliparity by cohort and by subgroups of exposure to the technogenic niche (education, income, urbanization), using standardized sources (Human Fertility Database 2025; see also Jasilioniene et al. 2016). — Age at first child by status/education quantiles and distribution of the interval until the first child, to detect timing frictions (Human Fertility Database 2025). — Assortativity coefficients in couples (education/status), tracking the trend of reinforced homophily in digitized ecologies (Kalmijn 1998; Schwartz 2013) and its covariance with the mediatization of encounter (Rosenfeld, Thomas, and Hausen 2019). — Prevalence of sexual inactivity/inexperience by age and sex in national surveys (Ueda et al. 2020; Ghaznavi et al. 2019) and its relation to digital mediation indicators. — Mental health and parenthood: relative risk of nulliparity and time to conception by profiles of own and partner's depression (Liao et al. 2024; Golovina et al. 2023; Kailaheimo-Lönnqvist et al. 2024).

Environmental contingency is part of the philosophical and empirical proof: if policies that reduce the material costs of parenthood and infrastructures that facilitate non-metric encounters decrease involuntary celibacy or anticipate the first child, then the selective process operates through the environment we manufacture — not through immutable essences. It is this differential response, measured over decades and compared across cohorts, that confirms 2nd-order selection.

These indicators are philosophical operators, not just illustrations: they function as materialist proxies for reproductive costs and benefits under the technogenic niche. Their interpretation requires causal caution (context, cohorts, heterogeneity), but it is precisely this contingency that makes them probative for 2nd-degree selection.

Conclusion

What is established is simple and operative: the human form is not final because natural selection continues to act, today primarily in the second-degree, technogenic natural environment that the species itself manufactures. The form, understood as the integrated configuration of the human, is therefore a local stability subject to reparameterizations whenever the environment changes.

The originality of this proposal is not in claiming an isolated discovery, but in articulating four threads that rarely appear together: a materialist ontology without dualisms between nature and technology; the distinction between first- and second-degree environments; the centrality of differential reproduction as a criterion for effective change; and the translation of the effects of digital mediation into nameable mechanisms — metric proximity, funnel effect, quantile matching, reproductive archipelago — with verifiable metrics.

A practical consequence follows from this framework: there is no fixed destiny