Now that you have finished reading this chapter, you are equipped to understand the historical and political dimensions of evolution. Evolution is an ongoing process of change and diversification. Evolutionary theory is a tool that we use to understand this process. The development of evolutionary theory is shaped both by scientific innovation and political engagement. Since Darwin first articulated natural selection as an observable mechanism by which species adapt to their environments, our understanding of evolution has grown. Initially, scientists focused on the adaptive aspects of evolution. However, with the emergence of genetics, our understanding of heredity and the level at which evolution acts has changed. Genetics led to a focus on the molecular dimensions of evolution. For some, this focus resulted in reductive accounts of evolution. Further developments in our understanding of evolution shifted our view to epigenetic processes and how organisms shape their own evolutionary pressures (e.g., niche construction).
Evolutionary theory will continue to develop in the future as we invent new technologies, describe new dimensions of biology, and experience cultural changes. Current innovations in evolutionary theory are asking us to consider evolutionary forces beyond natural selection and genetics to include the ways organisms shape their environments (niche construction), inheritances beyond genetics (inclusive inheritance), constraints on evolutionary change (developmental bias), and the ability of bodies to change in response to external factors (plasticity). The future of evolutionary theory looks bright as we continue to explore these and other dimensions. Biological anthropology is well-positioned to be a lively part of this conversation, as it extends standard evolutionary theory by considering the role of culture, social learning, and human intentionality in shaping the evolutionary trajectories of humans (Zeder 2018). Remember, at root, human evolutionary theory consists of two propositions: (1) the human species is descended from other similar species and (2) natural selection has been the primary agent of biological adaptation. Pretty much everything else is subject to some degree of contestation.