In order to introduce protists to philosophers, we outline the diversity, classification, and evolutionary importance of these eukaryotic microorganisms. We argue that an evolutionary understanding of protists is crucial for understanding eukaryotes in general. More specifically, evolutionary protistology shows how the emphasis on understanding evolutionary phenomena through a phylogeny-based comparative approach constrains and underpins any more abstract account of why certain organismal features evolved in the early history of eukaryotes. We focus on three crucial episodes of this history: the origins (...) of multicellularity, the origin of sex, and the origin of the eukaryote cell. Despite ongoing uncertainty about where the root of the eukaryote tree lies, and residual questions about the precise endosymbioses that have produced a diversity of photosynthesizing eukaryotes, evolutionary protistology has illuminated with considerable clarity many aspects of protist evolution. Our main message in light of evolutionary protistology is that these ‘other eukaryotes’ are in fact the organisms through which the rest of the eukaryotes should be understood. (shrink)

This paper investigates the complexity hypothesis in microbial evolutionary genetics from a philosophical vantage. This hypothesis, in its current version, states that genes with high connectivity are likely to be resistant to being horizontally transferred. We defend four claims. There is an important distinction between two different ways in which a gene family can persist: vertically and horizontally. There is a trade-off between these two modes of persistence, such that a gene better at achieving one will be worse at achieving (...) the other. At least some genes are likely to experience selection favoring increased transferability. One consequence of this can be encapsulated as the “simplicity hypothesis”: horizontally persisting genes will experience selection favoring reduced connectivity. In order to make sense of the simplicity hypothesis, we need to consider evolutionary populations that transcend species boundaries. Vertical and horizontal persistence are therefore not two competing ways of succeeding at the same game, but involve playing two different games altogether. The complexity hypothesis can be understood in terms of two related notions: entrenchment and Cuvierian functionalism. This framing reveals previously unrecognized and philosophically interesting connections between reasoning about deep conservation and horizontal transfer. (shrink)

How to reconcile the theory of evolution with existing religious beliefs has occupied minds since Darwin's time. The majority of the discourse on the subject is still focused on the Darwinian version of evolutionary theory, or at best, the mid-twentieth century version of the Modern Synthesis. However, evolutionary thought has moved forward since then with the insights provided by the advent of comparative genomics in recent decades having a particularly significant impact. A theology that successfully incorporates evolutionary biology needs to (...) take such developments into account, because range of truly viable options among the many versions of theistic evolution that have been proposed in the past may narrow down when this is done. Here I present these previously underappreciated strains of contemporary evolutionary thought and discuss their potential theological impact. (shrink)

This is the second of a two-part essay on the history of debates concerning the creativity of natural selection, from Darwin through the evolutionary synthesis and up to the present. In the first part, I focussed on the mid-late nineteenth century to the early twentieth, with special emphasis on early Darwinism and its critics, the self-styled “mutationists.” The second part focuses on the evolutionary synthesis and some of its critics, especially the “neutralists” and “neo-mutationists.” Like Stephen Gould, I consider the (...) creativity of natural selection to be a key component of what has traditionally counted as “Darwinism.” I argue that the creativity of natural selection is best understood in terms of selection initiating evolutionary change, and selection directing evolutionary change, for example by creating the variation that it subsequently acts upon. I consider the respects in which both of these claims sound non-Darwinian, even though they have long been understood by supporters and critics alike to be virtually constitutive of Darwinism. (shrink)