The Conceptualization of Evolutionary Theory

The main theme of my research is the conceptual foundation of Evolutionary theory. I recently completed my PhD I on this topic. Below is the abstract:

My thesis examines the theoretical and philosophical underpinnings of the concept of natural selection which is pervasively invoked in biology and other ‘evolutionary’ domains. Although what constitutes the process of natural selection appears to be very intuitive (natural selection results from entities exhibiting differences in fitness in a population), this conceals a number of theoretical ambiguities and difficulties. Some of these have been pointed out numerous times; others have hardly been noticed. One aim of this work is to unpack these difficulties and ambiguities; another is to provide new solutions and clarifications to them using a range of philosophical and conceptual tools. The result is a concept of natural selection stripped down from its biological specificities.

I start by revisiting the entangled debates over whether natural selection is a cause of evolutionary change as opposed to a mere statistical effect of other causes, at what level this putative cause operates and whether it can be distinguished from drift. Borrowing tools from the causal modelling literature, I argue that natural selection is best conceived as a causal process resulting from individual level differences in a population. I then move to the question of whether the process of natural selection requires perfect transmission of types. I show that this question is ambiguous and can find different answers. From there, I distinguish the process of natural selection from some of its possible products, namely, evolution by natural selection and complex adaptation. I argue that reproduction and inheritance are conceptually distinct from natural selection, and using individual-based models, I demonstrate that they can be conceived as evolutionary products of it. This ultimately leads me to generalise the concepts of heritability and fitness used in the formal equations of evolutionary change. Finally, I argue that the concepts of fitness and natural selection crucially depend on the grains of description at and temporal scales over which evolutionary explanations are given. These considerations reveal that the metaphysical status of the process of natural selection is problematic and why neglecting them can lead to flawed arguments in the levels of selection debate.

The Interplay between Biological and Cultural Evolution

I am interested in the links between biological and cultural evolution. This involves a number of questions to which part of my research is dedicated:

  • Are biological and cultural evolution two instances of a more general phenomenon?
  • Is there a unit of selection in cultural evolution, and if there is, what is this unit?
  • At which temporal scale biological and cultural evolutions occur?

One particular question I have been working on recently is whether biological and cultural evolution requiert replicators. Evolutionary biology has often been used as a model for studies in cultural evolution. But it is under appreciated that raising questions in the domain of cultural evolution can have feedbacks on our understanding of Evolutionary Theory generally and evolutionary biology more particularly. For instance, the notion of “meme” — a cultural anologue to “gene” — has been largely criticzed in recent years. One common critcism is that contrary to genes, cultural entities do not replicate but are reproduced over time. For this criticism to be fair, one must ask whether genes are themeselves truly replicated rather than merely reproduced. In my thesis, I demonstrate that the answer to this question is far from obvious.

The Evolution of Religion

The origins and evolution of Religion is a topic that has received an increasing interest from researchers over the last 20 years. This field being quite new, a lot of theoretical work remains to be done and this involves many disciplines (biology, psychology, anthropology, etc). One challenge I have undertaken is to integrate much of the knowledge brought by each specialized discipline into a coherent evolutionary framework.