Domestication as a model system for the extended evolutionary synthesis

Abstract

One of the challenges in evaluating arguments for extending the conceptual framework of evolutionary biology involves the identification of a tractable model system that allows for an assessment of the core assumptions of the extended evolutionary synthesis (EES). The domestication of plants and animals by humans provides one such case study opportunity. Here, I consider domestication as a model system for exploring major tenets of the EES. First I discuss the novel insights that niche construction theory (NCT, one of the pillars of the EES) provides into the domestication processes, particularly as they relate to five key areas: coevolution, evolvability, ecological inheritance, cooperation and the pace of evolutionary change. This discussion is next used to frame testable predictions about initial domestication of plants and animals that contrast with those grounded in standard evolutionary theory, demonstrating how these predictions might be tested in multiple regions where initial domestication took place. I then turn to a broader consideration of how domestication provides a model case study consideration of the different ways in which the core assumptions of the EES strengthen and expand our understanding of evolution, including reciprocal causation, developmental processes as drivers of evolutionary change, inclusive inheritance, and the tempo and rate of evolutionary change.

Keywords: coevolution; cooperation; domestication; ecological inheritance; evolvability; niche construction theory.

Figure 1.

Currently recognized areas of domestication of plants and animals with some examples of plants and animals domesticated in each centre. 1, Eastern North America: chenopodia, squash, sunflower, knotweed and maygrass; 2, Southwest US: turkeys; 3, Mesoamerica: maize, squash, beans and turkeys; 4, northern Peru/Ecuador: squash and lima beans; 5, Amazonia: manioc, yams, peanuts and Muscovy duck; 6, Andes: oca, potato, quinoa, amaranth, llama, alpaca and guinea pigs; 7, sub-Saharan Africa: pearl millet, sorghum and African rice; 8, Horn of Africa/Nile Valley: asses, tef; 9, Near East: wheat, barley, lentils, peas, sheep, goats, taurine cattle and pigs; 10, Central Asia: horses, golden hamster; 11, South Asia: browntop millet, water buffalo and zebu cattle; 12, North China: foxtail and broomcorn millet; 13, South China/Southeast Asia: rice and chickens; 14, Japan: barnyard millet, mung bean, burdock; and 15, New Guinea: bananas, yams and taro. Note: list of domesticates not exhaustive.