Clade selection is unpopular with philosophers who otherwise accept multilevel selection theory. Clades cannot reproduce, and reproduction is widely thought necessary for evolution by natural selection, especially of complex adaptations. Using microbial evolutionary processes as heuristics, I argue contrariwise, that (1) clade growth (proliferation of contained species) substitutes for clade reproduction in the evolution of complex adaptation, (2) clade-level properties favoring persistence – species richness, dispersal, divergence, and possibly intraclade cooperation – are not collapsible into species-level traits, (3) such properties (...) can be maintained by selection on clades, and (4) clade selection extends the explanatory power of the theory of evolution. (shrink)

According to many philosophical accounts, health is related to the functions and capacities of biological parts. But how do we decide what constitutes the health subject (that is, the bearer of health and disease states) and its biological parts whose functions are relevant for assessing its health? Current science, especially microbiome science, complicating the boundaries between organisms and their environments undermines any straightforward answer. This article explains why this question matters, delineates a few broad options, offers arguments against one option, (...) and draws some modest implications for philosophical accounts of human health. (shrink)

Cancer biology features the ascription of normal functions to parts of cancers. At least some ascriptions of function in cancer biology track local normality of parts within the global abnormality of the aberration to which those parts belong. That is, cancer biologists identify as functions activities that, in some sense, parts of cancers are supposed to perform, despite cancers themselves having no purpose. The present paper provides a theory to accommodate these normal function ascriptions—I call it the Modeling Account of (...) Normal Function (MA). MA comprises two claims. First, normal functions are activities whose performance by the function-bearing part contributes to the self-maintenance of the whole system and, thereby, results in the continued presence of that part. Second, MA holds that models of system-level activities that are (partly) constitutive of self-maintenance are improved by including a representation of the relevant function-bearing part and by making reference to the activity/activities that part performs which contribute(s) to those system-level activities. I contrast MA with two other accounts that seek to explicate the ascription of normal functions in biology, namely, the organizational account and the selected effects account. Both struggle to extend to cancer biology. However, I offer ecumenical readings which allow them to recover some ascriptions of normal function to parts of cancers. So, though I contend that MA excels in this respect, the purpose of this paper is served if it provides materials for bridging the gap between cancer biology, philosophy of cancer, and the literature on function. (shrink)

I develop an account of ecological role functions—the functions of species within ecosystems—which is informed by alternative regime phenomena in ecology. My account is a causal-role theory which includes a counterfactual sensitivity condition. The account tracks and explains a distinction ecologists make between functions and various activities which are not functions. My counterfactual sensitivity condition resolves the liberality problem often attributed to causal-role theories of function, while also illuminating the explanatory centrality of role functions within ecology.

This paper discusses Millstein’s criticism of the consensus view formed against selected-effects ecological functions. I argue that Millstein’s defense of coevolution-based selected-effects ecological functions applies to a notion of function as an activity, whereas proponents of the consensus view are concerned with a notion of ecological function as the contribution of an organism, population, species, or abiotic item to the maintenance of its community and/or the functioning of its ecosystem. Millstein’s arguments hence do not invalidate the consensus view but draw (...) attention to a notion of function that has been neglected in philosophical discussions and that deserves more attention. (shrink)

This paper reinforces the current consensus against the applicability of the selected effect theory of function in ecology. It does so by presenting an argument which, in contrast with the usual argument invoked in support of this consensus, is not based on claims about whether ecosystems are customary units of natural selection. Instead, the argument developed here is based on observations about the use of the function concept in functional ecology, and more specifically, research into the relationship between biodiversity and (...) ecosystem functioning. It is argued that a selected effect account of ecological functions is made implausible by the fact that it would conflict with important aspects of the understanding of function and ecosystem functional organization which underpins functional ecology’s research program. Specifically, it would conflict with (1) Functional ecology’s adoption of a context-based understanding of function and its aim to study the functional equivalence between phylogenetically-divergent organisms; (2) Functional ecology’s attribution to ecosystems of a lower degree of part-whole integration than the one found in paradigm individual organisms; and (3) Functional ecology’s adoption of a physiological or metabolic perspective on ecosystems rather than an evolutionary one. (shrink)

This article offers an analysis of ecologist Charles Elton’s “functional” concept of the niche and of the notion of function implicitly associated with it. It does so in part by situating Elton’s niche concept within the broader context of the “functionalist-interactionist” approach to ecology he introduced, and in relation to his views on the relationship between ecology and evolution. This involves criticizing the common claim that Elton’s idea of species as fulfilling functional roles within ecological communities committed him to an (...) idea of communities as units of selection. While such a claim implicitly attributes to Elton an understanding of function along the lines of the selected-effects theory of function advocated by many biologists and philosophers of biology, Elton’s use of the niche concept, I maintain, involves an understanding of function more along the lines of alternative nonselectionist theories such as the causal-role, goal-contribution, and organizational theories. I also briefly discuss how ecologists after Elton also tend to have typically adopted a nonselectionist understanding of the function concept, similar to his. (shrink)

This paper analyzes recent attempts to reject reproduction with lineage formation as a necessary condition for evolution by means of natural selection :560–570, 2008; Stud Hist Philos Sci Part C Stud Hist Philos Biol Biomed Sci 42:106–114, 2011; Bourrat in Biol Philos 29:517–538, 2014; Br J Philos Sci 66:883–903, 2015; Charbonneau in Philos Sci 81:727–740, 2014; Doolittle and Inkpen in Proc Natl Acad Sci 115:4006–4014, 2018). Building on the strengths of these attempts and avoiding their pitfalls, it is argued that (...) a robust formulation of evolution by natural selection without reproduction can be established. The main contribution of this paper is a reformulation of Lewontin’s three principles stating that minimal evolution by natural selection occurs when two conditions are met in a population: fitness-related variation and memory. Paradigmatic evolution by natural selection, which can generate adaptations, takes place when an additional condition is present, namely regeneration. (shrink)

This chapter argues that the common claim that the ascription of ecological functions to organisms in functional ecology raises issues about levels of natural selection is ill-founded. This claim, I maintain, mistakenly assumes that the function concept as understood in functional ecology aligns with the selected effect theory of function advocated by many philosophers of biology (sometimes called “The Standard Line” on functions). After exploring the implications of Wilson and Sober’s defence of multilevel selection for the prospects of defending a (...) selected effect account of ecological functions, I identify three main ways in which functional ecology’s understanding of the function concept diverges from the selected effect theory. Specifically, I argue (1) that functional ecology conceives ecological functions as context-based rather than history-based properties of organisms; (2) that it attributes to the ecological function concept the aim of explaining ecosystem processes rather than with that of explaining the presence of organisms within ecosystems; and (3) that it conceives the ecological functions of organisms as use and service functions rather than design functions. I then discuss the extent to which the recently proposed causal role and organizational accounts of ecological functions better accord with the purposes for which the ecological concept is used in functional ecology. (shrink)

The goal of this essay is to assess the Selected-Effects Etiological Theory of biological function, according to which a trait has a function F if and only if it has been selected for F. First, I argue that this approach should be understood as describing the paradigm case of functions, rather than as establishing necessary and sufficient conditions for function possession. I contend that, interpreted in this way, the selected-effects approach can explain two central properties of functions and can satisfactorily (...) address some recent counterexamples. This reading, however, shows that there is only a partial overlap between biological functions and selected effects, so the former cannot be reduced to the latter. Finally, I maintain that this result is still compatible with a naturalistic theory of function that appeals to some evolutionary process. (shrink)

I examine the use of the term function in Aldo Leopold’s land ethic, invoked as (1) the healthy functioning of the land community, which is dependent on (2) the maintenance of the characteristic functions of populations that are parts of the land community. The latter can be understood as referring to interactions between species that are the products of coevolution (such as parasite-host, predator-prey) and, thus, in terms of the “selected effect” account of function. The performance of these functions under (...) certain conditions maintain what Leopold took to be the healthy functioning of a land community. (shrink)

The etiological account of function defines a part’s/trait’s function as whatever that part/trait does and was selected for doing. Some philosophers have tried to employ this as an account of biological interests, claiming that to benefit an organism is to promote its etiological functioning and to harm it is to inhibit such functioning. I argue that etiological functioning is not a good account of biological interests. I first describe the history of theories of biological interests, explaining the special role that (...) etiological accounts of function have played within such theories. Second, I explain the problems with allowing etiological accounts of function to play this role and consider objections to my line of argument. Finally, I consider the theoretical alternatives to etiological function accounts of interests and assess their advantages and disadvantages. (shrink)

David Steen and co-authors in this journal offer a philosophical argument to support an “Evolutionary Community Concept” to identify what they call “evolutionary communities.” They describe these as “unique collections of species that interact and have co-evolved in a given geographic area” and that include “co-evolved dependencies between different parts of a community.” Steen et al. refer to the coevolution of assemblages, collections, communities, dependencies, interspecific and abiotic interactions, and traits, but they do not define “co-evolution” or provide an example (...) in which co-evolution has been demonstrated. There may be as many ways to explain interactions among species as these interactions themselves; they may result, for example, from ecological fitting and phenotypic plasticity. In this paper, I argue that standard Darwinian Theory explains intraspecific microevolution or descent with modification within an interbreeding and potentially continuous population. The power, mechanism, or force that causes interspecific co-evolution, especially at the community scale, requires further explanation. (shrink)

If ecological systems are functionally organised, they can possess functions or malfunctions. Natural function would provide justification for conservationists to act for the protection of current ecological arrangements and control the presence of populations that create ecosystem malfunctions. Invasive species are often thought to be malfunctional for ecosystems, so functional arrangement would provide an objective reason for their control. Unfortunately for this prospect, I argue no theory of function, which can support such normative conclusions, can be applied to large scale (...) ecosystems. Instead ecological systems have causal structure, with small clusters of populations achieving functional arrangement. This, however, does not leave us without reason to control invasive species. We can look at the causal arrangement of ecological systems for populations that support ecological features that we should preserve. Populations that play a causal role in reducing biodiversity should be controlled, because biodiversity is a good all prudent agents should want to preserve. (shrink)

Evolution by natural selection has been extended to several supraorganismic levels, but whether it can apply to ecosystems remains controversial on two main counts. First, local ecosystems are loosely individuated, so that it is unclear how they manifest heredity and fitness. Second, even if they did, the meta-ecosystem formed by this population of local ecosystems will also suffer from a very low degree of cohesion, which will jeopardize any ENS. We suggest a way to overcome both issues, focusing on ecosystem (...) properties rather than on ecosystemic individuals. First, we follow recent theoretical developments which deny the centrality of reproduction in ENS. This leads us to merge heredity and fitness in a single process, in which a local ecosystem causally influences its neighbors, in a way responsible for their phenotypic similarity. Second, we suggest that the resulting meta-ecosystem need not meet the criteria of individuality. Instead, the evolving meta-ecosystem is best understood as a homeostatic property cluster, i.e., a set of phenotypes that together evolve by ENS at the ecosystem level. We illustrate this conceptual framework with a hypothetical example of local ecosystems that vary in terms of stability, productivity, diversity, and complementarity between species. Finally, we stress that our property-based account of ecosystemic ENS can help understand evolution at other biological levels, such as early life evolution and holobionts. (shrink)

Microbiologists are transitioning from the study and characterization of individual strains or species to the profiling of whole microbiomes and microbial ecology. Equipped with high-throughput methods for studying the taxonomic and functional characteristics of diverse samples, they are just beginning to encounter the conceptual, theoretical, and experimental problems of comparing taxonomy to function, and extracting useful measures from such comparisons. Although still unresolved, these problems are well studied in macro-ecology and are reiterated here as an historical precautionary for microbial ecologists. (...) Beyond expected and unresolved terminological vagueness, we argue that assessments and comparisons of taxonomic and functional profiles in micro-ecology suffer from theoretically unresolvable arbitrariness and ambiguities. We divide these into problems of scale, individuation, and commensurability. We argue that there is no technically/theoretically “correct” scale, individuation, or comparison of taxonomy and function, but there are nonetheless better and worse methodologies for profiling. (shrink)