Is Domestication Speciation? The Implications of a Messy Domestication Model in the Holocene

Abstract

Domestication is one of the fundamental process that has shaped our world in the last 12,000 years. Changes in the morphology, genetics, and behavior of plants and animals have redefined our interactions with our environments and ourselves. However, while great strides have been made towards understanding the mechanics, timing, and localities of domestication, a fundamental question remains at the heart of archaeological and scientific modelling of this process—how does domestication fit into a framework of evolution and natural selection? At the core of this is the ontological problem of what is a species? In this paper, the complicated concepts and constructs underlying ‘species’ and how this can be applied to the process of domestication are explored. The case studies of soybean and proto-indica rice are used to illustrate that our choice of ‘species’ definitions carries with it ramifications for our interpretations, and that care needs to be made when handling this challenging classificatory system.

What is domestication?

“…There is certainly no lack of attempts to define domestication and tease apart its core characteristics and there have been several discussions on differing approaches to defining this process [3,[5][6][7][8][9][10]. Previous definitions of domestication may (or may not) include: (i) the idea of evolutionary change; (ii) control of the process by humans, including the invocation of human intentionality; (iii) the concept of mutualism; (iv) benefits derived by humans; (v) the action of artificial selection; and (vi) enumeration of common domesticate phenotypes [3,[5][6][7][8][9][10].…”

“…In crafting a definition of domestication, the thoughtful analysis provided by Zeder [7], whose own definition leans heavily on ideas by Rindos and others [14][15][16][17][18], can serve as a starting point. Synthesizing these and other perspectives [3,5,6,[8][9][10], a broad biological definition of domestication is that it is a coevolutionary process that arises from a mutualism, in which one species (the domesticator) constructs an environment where it actively manages both the survival and reproduction of another species (the domesticate) in order to provide the former with resources and/or services (Figure 2). This allows for increased fitness for the interacting organisms within the mutualistic relationship, leading to the evolution of traits that ensures the stable association of domesticator and domesticate across generations.…”