Testing the “(Neo-)Darwinian” Principles against Reticulate Evolution: How Variation, Adaptation, Heredity and Fitness, Constraints and Affordances, Speciation, and Extinction Surpass Organisms and Species

Abstract

<jats:p>Variation, adaptation, heredity and fitness, constraints and affordances, speciation, and extinction form the building blocks of the (Neo-)Darwinian research program, and several of these have been called “Darwinian principles.” Here, we suggest that caution should be taken in calling these principles Darwinian because of the important role played by reticulate evolutionary mechanisms and processes in also bringing about these phenomena. Reticulate mechanisms and processes include symbiosis, symbiogenesis, lateral gene transfer, infective heredity mediated by genetic and organismal mobility, and hybridization. Because the “Darwinian principles” are brought about by both vertical and reticulate evolutionary mechanisms and processes, they should be understood as foundational for a more pluralistic theory of evolution, one that surpasses the classic scope of the Modern and the Neo-Darwinian Synthesis. Reticulate evolution moreover demonstrates that what conventional (Neo-)Darwinian theories treat as intra-species features of evolution frequently involve reticulate interactions between organisms from very different taxonomic categories. Variation, adaptation, heredity and fitness, constraints and affordances, speciation, and extinction therefore cannot be understood as “traits” or “properties” of genes, organisms, species, or ecosystems because the phenomena are irreducible to specific units and levels of an evolutionary hierarchy. Instead, these general principles of evolution need to be understood as common goods that come about through interactions between different units and levels of evolutionary hierarchies, and they are exherent rather than inherent properties of individuals.</jats:p>

Reticulate evolution underlies synergistic trait formation in human communities

“…Symbiosis is an ecological phenomenon first defined in 1879 by Anton de Bary as the living together of unlike-named organisms. 24 Symbiotic associations are either facultative or obligate, and they can occur haphazardly or repeat over generations through time in which case they can become necessary and hereditary. 25 Symbiotic interactions can be neutral, beneficial, or harmful for one or all of the participants in the symbiosis (Table 1).…”

“…70 History demonstrates that domesticated animals and plants have a longer species life span than their wild counterparts. 24 The auroch (Bos primigenius), for example, which is ancestral to modern domesticated bovines, has long died out, but its descendants live on through the symbiotic associations maintained with humans. Such can be understood in mutualist terms because both symbiotic partners keep one another alive.…”

“…102 Symbiosis has even been implicated in social communication because the microbiome affects body odor 103 and as such it forms barriers to social group identification, sexual attraction, and mate choice. 24 Much of this remains virgin territory awaiting further exploration, but it is already safe to say that microbiome studies can complement the classic theories that understand the rise of language in hominin society as a form of vocal grooming 85 enabling speakers to address larger crowds.…”

“…These were first distinguished by Pierre Joseph van Beneden in 1875 in the context of research on the “social” interactions that exist between different organisms. Van Beneden thus already emphasized that symbiosis requires social or community living 24 …”

“…But by taking our predatory place in the ecological food web, humans can also contribute to maintaining and facilitating the populations of other animal and plant species 70 . History demonstrates that domesticated animals and plants have a longer species life span than their wild counterparts 24 . The auroch ( Bos primigenius ), for example, which is ancestral to modern domesticated bovines, has long died out, but its descendants live on through the symbiotic associations maintained with humans.…”