VI. Earth Life Emergence: Development of Body, Brain, Selves and Societies
8. An Emergent Evolutionary Transition to a Personsphere Progeny
As this site tracks the scientific and academic literature, a growing trend is the widespread acceptance of this nested, repetitive scale as a way to define life’s episodic emergence from replicative biomolecules to human linguistic societies. It was first conceived in two volumes The Major Transitions in Evolution, (1995) and The Origins of Life (1999) by the theoretical biologists John Maynard Smith and Eors Szathmary. They are reviewed in Systems Evolution, along with many reports on their presence across fauna, flora, neural, and group instances. The original seven stages are shown in Ascent of Genetic Information since each comes with a certain code. This robust 21st century version of an oriented sequence from which people arise now sets aside an old Darwinian aimless, contingency, which as yet remains in textbooks.
Major Transitions in Evolution. www.thegreatcourses.com/courses/major-transitions-in-evolution. A 24 part presentation of this 21st century model of life’s nested, scalar emergence from replicative biochemicals to human culture. Conceived by John Maynard Smith and Eors Szathmary in the 1990s (search each), as evinced by a Great Course edition, it is now a widely accepted and availed replacement for gradual, Darwinian drift. But, we note, the old aimless version remains in textbooks, which still denies any direction or human phase. See Szathmary’s 2015 update Toward Major Evolutionary Transitions Theory 2.0 in PNAS (112/10104).
How and when did life on Earth get to be the way it is today? Imagine a world without bees, butterflies, and flowering plants. That was Earth 125 million years ago. Turn back the clock 400 million years, and there were no trees. At 450 million years in the past, even the earliest insects had not yet developed. And looking back 500 million years-a half-billion years before the present-the land was devoid of life, which at that time flourished in a profusion of strange forms in the oceans. These and other major turning points are the amazing story of evolution, the most remarkable force in the history of Earth, the organizing principle throughout the biological sciences, and the most important mechanism scientists use to understand the varieties of life on our planet.
Andersson, Claes and Petter Tornberg. Toward a Macroevolutionary Theory of Human Evolution: The Social Protocell. Biological Theory. 14/2, 2019. Within a context of the major transitions in individuality scale, Chalmers University of Technology, Sweden systems scholars achieve an overdue perception whereof societal groupings can take on a guise akin to life’s original protocells. As early hominins form symbiotic bands, they achieve adaptive internal reciprocities as cellular wholes within Wholes. A tacit principle is an emergent recurrence of the same pattern and process. In each case, a bounded unit leads which then fosters cooperation, knowledge gain and selfhood in community. By way of this nested procession, life’s rise accrues “new channels of inheritance” and an oriented direction. In regard, this website has been citing a “social protocell” for some time, especially in Ecovillages. See also Group-Level Social Knowledge by Elizabeth Hobson, et al at arXiv:1810.07215 and The Cultural Brain Hypothesis by Michael Muthukrishna et al in PLoS Computational Biology (Nov. 2018) for other takes.
Despite remarkable empirical and methodological advances, our theoretical understanding of the evolutionary processes that made us human remains fragmented and contentious. Here, we make the radical proposition that the cultural communities within which Homo emerged may be understood as a novel exotic form of organism. The argument begins from a deep congruence between robust features of Pan community life cycles and protocell models of the origins of life. We argue that if a cultural tradition, meeting certain requirements, arises in the context of such a “social protocell,” the outcome will be an evolutionary transition in individuality. By so doing, traditions and hominins coalesce into a macroscopic bio-socio-technical system, with an organismal organization that is culturally inherited. We refer to this hypothetical evolutionary individual as a “sociont.” We go on to hypothesize that the fate of the hominin would be mutualistic coadaptation into a part-whole relation with the sociont. (Abstract excerpt)
Bourke, Andrew F. G. Principles of Social Evolution. Oxford: Oxford University Press, 2011. A University of East Anglia behavioral zoologist integrates the study of animal assemblies across many phyla into the major evolutionary transitions scale to gain a vital perspective. Life’s evident, sequential propensity to form cooperative groupings is then braced by factoring in inclusive fitness, (kin selection) theory. An expanded sense of recurrent communities from prokaryote microbes to homo sapiens can then be described. Bourke goes on to affirm the earlier work of Leo Buss (1987) who perceives a consistent “evolution of individuality” at each stage. With Brett Calcott (2011), Selin Kesebir (2012) and others, another confirmation of this major episodic model is stated, a latter, temporal “scala naturae.”
Bourrat, Pierrick. Evolutionary Transitions in Heritability and Individuality. Theory in Biosciences. Online May, 2019. A Macquarie University, Sydney philosopher of biology (search) continues to finesse and advance understandings of this nested, episodic, accepted model of life’s regnant reciprocity of persons in communities. See also Trait Heritability in Major Transitions by Matthew Herron, et al in BMC Biology (16/145, 2018).
The literature on evolutionary transitions in individuality (ETIs) has mostly focused on the relationships between lower-level (particle-level) and higher-level (collective-level) selection, leaving aside contrasts between particle-level and collective-level inheritance. To that effect, I present a model to study particle-level and collective-level heritability both when a collective-level trait is a linear function and when it is a non-linear function of a particle-level trait. The upshot is that population structure is a driver for ETIs. (Abstract excerpt)
Calcott, Brett and Kim Sterelny, ed. The Major Transitions in Evolution Revisited. Cambridge: MIT Press, 2011. The volume is a decadal update upon this major theoretical advance, now much accepted, which still struggles with a nested scale of being and becoming from microbe to man at odds with prior Darwinian tenets. Players such as Daniel McShea, Samir Okasha, Peter Godfrey-Smith, and others wonder about its greater or lesser significance – is it really there, are the levels equal, what if anything drives its form, how about an evolving informational cause for each stage, and so on. While the overall pattern seems to evince an inherent self-organization, only one chapter by University of Adelaide philosopher Pamela Lyon touches upon complex dynamical systems. A summary retrospective by Eors Szathmary and Chrisantha Fernando goes on to note how this multilevel model quite provides a working structure for life’s evolutionary emergence.
In 1995, John Maynard Smith and Eörs Szathmáry published their influential book The Major Transitions in Evolution. The "transitions" that Maynard Smith and Szathmáry chose to describe all constituted major changes in the kinds of organisms that existed but, most important, these events also transformed the evolutionary process itself. The evolution of new levels of biological organization, such as chromosomes, cells, multicelled organisms, and complex social groups radically changed the kinds of individuals natural selection could act upon. Many of these events also produced revolutionary changes in the process of inheritance, by expanding the range and fidelity of transmission, establishing new inheritance channels, and developing more open-ended sources of variation. The contributors discuss different frameworks for understanding macroevolution, prokaryote evolution (the study of which has been aided by developments in molecular biology), and the complex evolution of multicellularity. (Publisher)
Carmel, Yohay and Ayelet Shavit. Operationalizing Evolutionary Transitions in Individuality. Proceedings of the Royal Society B. February, 2020. Technion-Israel Institute of Technology scholars present a most comprehensive study to date of life’s ratcheted, sequential, scalar emergence of distinct “personal” organisms at each stage, which is now accepted as a valid structure. As the Abstract says, an interplay of diverse component entities as they join in bounded interactivity repeats in kind at each nested phase. With this consistency thoroughly described, Yohay Carmel notes that he is now at work on their further application as our homo sapiens transitions its global anthropic worldly consummation.
Evolutionary transitions in individuality (ETIs), such as the transition to multi-cellularity and to social colonies, have been at the centre of evolutionary research, but only few attempts were made to systematically operationalize this concept. Here we devise a set of four indicators intended to assess the change in complexity during ETIs: system size, inseparability, reproductive specialization and non-reproductive specialization. We then conduct a quantitative comparison across multiple taxa and their ETI. Our analysis reveals that inseparability has a crucial role in the process; it seems irreversible and may mark the point where group members become a new individual at a higher hierarchical level. Interestingly, we find that disparate groups demonstrate a similar pattern of progression along ETIs. (Abstract)
Chavalarias, David. From Inert Matter to the Global Society: Life as Multi-level Networks of Processes. Philosophical Transactions of the Royal Society B. February, 2020. This synoptic survey which alludes to a next planetary phase is reviewed more in Network Physics.
Clarke, Ellen. Origins of Evolutionary Transitions. Journal of Biosciences. 39.2, 2017. In this Individuals and Groups issue, the All Souls College, Oxford, UK philosopher of biology surveys the lineaments and identities that drive and distinguish ascendant grouping of earlier, simpler wholes into new, beneficial, organism-like forms.
An ‘evolutionary transition in individuality’ or ‘major transition’ is a transformation in the hierarchical level at which natural selection operates on a population. In this article I give an abstract (i.e. level-neutral and substrate-neutral) articulation of the transition process in order to precisely understand how such processes can happen, especially how they can get started. (Abstract)
Czegel, Daniel, et al. Major Evolutionary Transitions as Bayesian Structure Learning. bioRxiv. Online June, 2018. Hungarian Academy of Sciences veteran theorists DC, Istvan Zacher, and Eors Szathmary scope out advanced methods to enhance this MET in Individuality scale, which ES and John Maynard Smith conceived in the 1990s. As proof of its validity, the nested repetitive scale (nominally 8 steps) from rudimentary genes and cells to societal language is now widely accepted. Herein an inclusion of an active knowledge-gaining faculty by way of scalar Bayesian iterations is proposed. With colleagues, the authors have pursued a parallel approach to view evolution as a learning process, see the Evolutionary Intelligence section.
Complexity of life forms on Earth has increased tremendously, primarily driven by subsequent evolutionary transitions in individuality, a mechanism in which units formerly being capable of independent replication combine to form higher-level evolutionary units. Although this process has been likened to the recursive combination of pre-adapted sub-solutions in the framework of learning theory, no general mathematical formalization has been provided yet. Here we show, building on work connecting replicator dynamics with Bayesian methods, that (i) evolution of a hierarchical population under multilevel selection is equivalent to inference in hierarchical Bayesian models, and (ii) evolutionary transitions in individuality, driven by synergistic fitness interactions, is equivalent hierarchical structures via Bayesian model comparisons. These correspondences support a learning based narrative of evolutionary complexification: the complexity and depth of the hierarchical structure of individuality mirrors the amount and complexity of data that has been integrated about the environment through the course of evolutionary history. (Abstract edits)
Dedeo, Simon. Major Transition in Political Order. arXiv:1512.03419. The Indiana University systems scientist applies this popular evolutionary scale (Szathmary) from replicator molecules to human communications onto a further civilizational phase. While prior stages are seen as based on how information is stored and conveyed, sapient societies arise and proceed more by how it is processed. A computational version is advanced to explain a “lossy” cleaning up or compression of this cultural transmission. A bit technical in style, see also The Evolution of Lossy Compression by DeDeo and Sarah Marzen at arXiv:1506.06138.
We present three major transitions that occur on the way to the elaborate and diverse societies of the modern era. Our account links the worlds of social animals such as pigtail macaques and monk parakeets to examples from human history, including 18th Century London and the contemporary online phenomenon of Wikipedia. From the first awareness and use of group-level social facts to the emergence of norms and their self-assembly into normative bundles, each transition represents a new relationship between the individual and the group. At the center of this relationship is the use of coarse-grained information gained via lossy compression. The role of top-down causation in the origin of society parallels that conjectured to occur in the origin and evolution of life itself. (Abstract)
Erwin, Douglas. Tempos and Modes of Collectivity in the History of Life. Theory in Biosciences. Online September, 2019. The National Museum of Natural History paleobiologist posts a latest explanatory synthesis for life’s well documented episodic, scalar emergence from bioreplicators to linguistic entities. In collaboration with Santa Fe Institute and Arizona State University theorists, Erwin adds a salutary aspect of a collective computation at work. A further vital inclusion is evolution as a learning process due to Richard Watson, Eors Szathmary (co-originator with John Maynard Smith of the major transitions view) and others. These expansions are then seen to bolster evidence for a constant convergence throughout. A surmise might be that along with nodal elements, integral nature is graced with an equally real propensity to join into symbiotic communal groupings which altogether survive and develop toward our composite humankinder perception. This article is part of the Special Issue on Quantifying Collectivity.
Collective integration and processing of information have increased through the history of life, through both the formation of aggregates in which the entities may have very different properties and which jointly coarse-grained environmental variables (ranging from microbial consortia to diverse coral reef species) and through collectives of similar entities (cells within an organism or social groups). Such increases have been implicated in significant transitions in the history of life, including aspects of the origin of life, the generation of pangenomes among microbes and stromatolite communities, multicellularity and social insects. Here we provide a preliminary overview of the dominant modes of collective information processing in the history of life, their phylogenetic distribution and extent of convergence, and the effects of new modes for integrating and acting upon information upon the tempo of evolutionary change. (Abstract)
Estrela, Sylvie, et al. Transitions in Individuality through Symbiosis. Current Opinion in Microbiology. 31/191, 2016. Biologists Estrela and Ben Kerr, University of Washington, and Jeff Morris, University of Alabama, seek to finesse the popular Major Transitions in Evolution scale whereby whence life’s course from unicellular microbes to multicellular organisms is occurred by a common mode of smaller, diverse entities which came together as a larger, cohesive, functionally reciprocal whole.
When a more complex, functionally integrated entity emerges from the association of simpler, initially independent entities, a major evolutionary transition has occurred. Transitions that result from the association of different species include the evolution of the eukaryotic cell and some obligate mutualisms. Recent studies are revolutionizing our understanding of how these intimate interspecific associations come to be, revealing how and to what extent each partner contributes to the relationship, and how partners mediate conflict. Here, we review work on the evolution of mutualistic symbioses in the context of transitions in individuality and highlight how a better mechanistic understanding of the ecological drivers of host-symbiont interdependencies can help elucidate the evolutionary path to symbiotic organismality. (Abstract)