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Post-Darwinism

The long-term continuity of genetic inheritance is now being questioned (Mor- ange 2006), partly because the preservation of the inherited structure of DNA from one generation to the next is doubted (Charney 2012), and partly because the evidence for the horizontal transfer of genetic material between bacteria (Chan & Bhattacharya 2013; Skippington & Ragan 2011), organisms (Dunning et al. 2019), and from viruses to host organisms can be both demonstrated experimentally and, as we all know only too well, experienced practically. In other words, the replication of lengths of DNA material (a.k.a. genes) does not appear to preserve the stability' of that material as was once thought and from this perspective the security' of species continuity appears to be vulnerable. The fact that long-term species stability' is witnessed in palaeontology might therefore reflect more on the continuity' with which genetic material is edited and interpreted than on the continuity of that material itself. If we allow that biological evolution is witnessed by changes in the composition of the reproducing population, given that populations are themselves characterised by the growth, development, and death of their individual members, then it follows that continuity lies in the inherited processes of development of the individuals that make up those populations, and that this depends more upon the continuities in the larger ecosystem than it does upon genetic continuity alone. This is a topic to which we must return in the next two chapters.

The emphasis placed upon genetics as the carrier of inherited information, as if this information alone operated as a set of instructions that determined the form of the organism, treats the form and behaviour of the organism (i.e., the phenotype) as if it was predetermined by the inherited units of genetic information. If, on the other hand, we treat the organism as an ongoing process of growth and development (Oyama 2000; Oyama et al. 2001), then the niche context towards which that organism’s life is orientated is the context that secured the continuity of the developmental process. Ingold and Palsson (2013), along with their colleagues, have characterised the organism whose form is determined by its inheritance as concerning the state of the ‘being’ of a particular life-form, and they have contrasted this with life as a process of‘becoming’. In other words, forms of life are not predetermined and given, instead they are processes of‘becoming’, they are developing and growing. The point of departure for Oyama, Ingold, Palsson, and others then becomes the move away from the neo-Darwinian programme at the point at which we might treat evolution not as the path followed by the transmission, under the control of natural selection, of the determinate units of genetic information, but as the changing processes by which particular forms of life have been able to develop and so bring themselves into existence by their use of the resources that are available to them (Godfrey-Smith 2009). As Ingold has argued, evolution:

does not lie in the mutation, recombination, replication and selection of transmissible traits. It is rather a life process. And at the heart of this process is ontogenesis. The failure to account for the ontogenetic emergence of phenotypic form is the Achilles heel of the entire neo-Darwinian paradigm. For it has proceeded as if the form were already there, prefigured in the virtual space of the genotype or its cultural equivalent. (Ingold 2013, 6)

The developmental processes that affect the growth of individual organisms and organic systems are more than the result of a genetic blueprint directing an individual’s development, given that genes (or for that matter memes, if either were to actually exist) do not actually do anything. The many developmental resources inherited by an individual, and which extend well beyond the DNA molecule, include the contexts that enable inherited information to be acted upon. Recent moves towards a ‘post-Darwinian’ model of evolution (Kull 1999) are therefore based upon the need to understand the evolution of the organism’s developmental processes that are directed towards its growth within particular niche ecologies (Oyama 2000).

From the perspective of evolutionary development (sometimes referred to as ‘EvoDevo’) the content or meaning of an information source, such as the DNA within a cell, or the food and resources of security beyond the organism, is not contained in the material itself but it is assembled by the processes enacted by the agency of a developing interpretant. It is an approach that is understood front the perspective of Peirce’s theory of semiotics (El-Hani et al. 2009). Peirce established semiosis as the processes in which an interpretant, having identified a sign as standing for some object or quality, responds to that identification. In biological terms the living cell contains facilities for which segments of DNA specify some mode of reaction by the interpretant, and where the interpretant should be seen as the process that traces the cell’s development.

The treatment of life as a semiotic process (Hoffmeyer 2008; Emmeche & Kull 2011; Kull et al. 2009) therefore questions any distinction that is drawn between a biological determinism, as applied to the agencies of the so-called natural or living world, and a cultural indeterminism, as it is applied to a human enculturated agency. By overcoming the naturexulture dichotomy in our understanding of the making of life, the process of semiosis means that we can understand the development of life in general as a process of self-definition and self-making (Maturana & Varela 1980). This self-making process is only possible because biological systems identify and interpret available sources of information and exploit the available sources of energy (metabolism) that together sustain a particular niche of adaptation (Odling-Smee et al. 2003). Understanding this process sustains the claim that life is, in general, conscious at various levels. This means that life recognises the conditions that sustain its development (Thompson 2007), and it therefore acts with intentionality (that is, it acts towards the object of material conditions that sustain it). If this argument is accepted then the discipline of biology is situated between what would today be regarded as the natural sciences and those regarded as the humanities.

Much has therefore changed, or is at least changing, to move us away from the gene-centred view of life that once so annoyed Gould (1980). It was Gould who commented on the emphasis upon genetics as ‘a theory developed entirely from understanding the nature of constituent matter in its smallest pieces’, a reductionist theory that has dominated the biological and ‘popular science’ literature in the third quarter of the last century (Huneman & Walsh 2017a). Today it is possible to chart our understanding of life’s diversity as shifting from a perception of that diversity as the result of the selective transmission of lineages of genetic information, towards a perception of life concerning the development of organisms as part of a wider ecology. Darwin chose to close his 1859 volume (along with all of its subsequent editions) with a contemplation upon ‘an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth’ (Darwin 2009 [1859], 426).

It was by this means that he invited reflection upon the processes that had constructed each of these diverse forms of life. We can now recognise this entangled bank as an ecology that cannot be characterised simply as if it were a mechanistic assemblage of separate genetic lineages; rather, it is a complex system of development where each part of the system is integrated within the whole, and where the whole displays emergent qualities that cannot be calculated as if the sum of the parts made up the whole. It is in this light that Capra and Luisi have noted that the:

outstanding property of all life is the tendency to form multileveled structures of systems within systems . . . cells combine to form tissues, tissues to form organs, and organs to form organisms. These in turn exist within social systems and ecosystems. . . . The properties of the parts are not intrinsic properties, but can be understood only within the context of the larger whole. (Capra & Luisi 2014, 64-66)

Conclusion

The critique of the neo-Darwinian synthesis rejects the idea that ‘the component processes of evolution - inheritance, development, innovation and adaptive population change - are discrete and quasi-autonomous’ (Huneman & Walsh 2017b, 2). We might also question the category of species that has achieved the status of describing the different kinds of life as if they were the relatively static building blocks making up an ecology' and operating as the mutable vehicles of Darwinian evolution. Perhaps we need to move beyond ideas of multispecies interaction (cf. Birch 2018) and find a language that better treats ecologies as complex systems (cf. Bak 1996), with the important implications for an archaeology that recognises forms of humanness as emergent within particular historical ecologies. Humanity has evolved, and continues to evolve, by its practices under the guise of these different forms of humanness. This kind of human history/evolution is generated by the processes of development which were made possible by means of the various networks through which materials, energy, and information had flowed. The methodological challenge for archaeology is therefore to understand the dynamic processes of becoming which had once occupied those material contexts whose residues are collected archaeologically.

 
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