In the cladistic literature, there is a recurrent perspective that considers homoplasy as something undesirable. Homoplasy, according to this view, is believed to obscure homologies that may lead to synapomorphies. Some cladists often call homoplasies an ad hoc hypothesis or an “error in our preliminary assignment of homology.” Consequently, homoplasy is generally regarded negatively, hindering further investigations, because it matters little whether a character subject to homoplasy is a convergence, a parallelism, or a reversal, since they all fall within the (...) problematic homoplastic category. Nixon and Carpenter developed one of the recent arguments supporting this vision. In this context, I will argue that phylogenetics, being a part of evolutionary biology, must be compatible with its principles. Therefore, I will discuss the idea that homoplasy is more complex than just nonhomology, sometimes even constituting evidence of common ancestry (e.g., parallelism). I will put forward the thesis that it is crucial to differentiate instances of convergence, parallelism, and reversions by incorporating recent advances from EvoDevo research. Ultimately, this approach aims to demonstrate that evolutionary biology and phylogenetics mutually complement each other and assist in providing different lines of evidence that can be used to test different evolutionary hypotheses. (shrink)

Recent rival attempts in the philosophy of science to put forward a general theory of the properties that all (and only) natural kinds across the sciences possess may have proven to be futile. Instead, I develop a general methodological framework for how to philosophically study kinds. Any kind has to be investigated and articulated together with the human aims that motivate referring to this kind, where different kinds in the same scientific domain can answer to different concrete aims. My core (...) contention is that non-epistemic aims, including environmental, ethical, and political aims, matter as well. This is defended and illustrated based on several examples of kinds, with particular attention to the role of social-political aims: species, race, gender, as well as personality disorders and oppositional defiant disorder as psychiatric kinds. Such non-epistemic aims and values need not always be those personally favoured by scientists, but may have to reflect values that matter to relevant societal stakeholders. Despite the general agenda to study ‘kinds,’ I argue that philosophers should stop using the term ‘natural kinds,’ as this label obscures the relevance of humans interests and the way in which many kinds are based on contingent social processes subject to human responsibility. (shrink)

The comparative method grants epistemic access to the biological past. Comparing lineages provides empirical traction on both hypotheses about particular lineages and models of trait evolution. Understanding this evidential role is important. Although philosophers have recently turned their attention to relations of descent, little work exists exploring the status of evidence from convergences. I argue that, where they exist, convergences play a central role in the confirmation of adaptive hypotheses. I focus on ‘analogous inferences’, show how such inferences ought to (...) be analysed and suggest three methods for strengthening their evidential weight. 1 Introduction2 Analogous Inferences2.1 Adaptive explanations and analogies2.2 Analogous inferences2.3 Scope, grain, and specificity3 Parallel Modelling, Integrated Explanations, and Convergent Modelling3.1 Parallel modelling3.2 Integrated explanations3.1 Convergent modelling4 Conclusion. (shrink)

Taxa and homologues can in our view be construed both as kinds and as individuals. However, the conceptualization of taxa as natural kinds in the sense of homeostatic property cluster kinds has been criticized by some systematists, as it seems that even such kinds cannot evolve due to their being homeostatic. We reply by arguing that the treatment of transformational and taxic homologies, respectively, as dynamic and static aspects of the same homeostatic property cluster kind represents a good perspective for (...) supporting the conceptualization of taxa as kinds. The focus on a phenomenon of homology based on causal processes (e.g., connectivity, activity-function, genetics, inheritance, and modularity) and implying relationship with modification yields a notion of natural kinds conforming to the phylogenetic-evolutionary framework. Nevertheless, homeostatic property cluster kinds in taxonomic and evolutionary practice must be rooted in the primacy of epistemological classification (homology as observational properties) over metaphysical generalization (series of transformation and common ancestry as unobservational processes). The perspective of individuating characters exclusively by historical-transformational independence instead of their developmental, structural, and functional independence fails to yield a sufficient practical interplay between theory and observation. Purely ontological and ostensional perspectives in evolution and phylogeny (e.g., an ideographic character concept and PhyloCode’s ‘individualism’ of clades) may be pragmatically contested in the case of urgent issues in biodiversity research, conservation, and systematics. (shrink)

Many of the current comparisons of taxic phylogenetic and biological homology in the context of morphology focus on what are seen as categorical distinctions between the two concepts. The first, it is claimed, identifies historical patterns of conservation and variation relating taxa; the second provides a causal framework for the explanation of this conservation and variation. This leads to the conclusion that the two need not be placed in conflict and are in fact compatible, having non-competing epistemic purposes or mapping (...) the same extensions in the form of monophyletic groupings (see Roth, The biological basis of homology 1–26, 1988; Sluys, J Zool Syst Evol Res 34:145–152, 1996; Abouheif, Trends Ecol Evol 12:405–408, 1997; Brigandt, J Exp Zool 299:9–17, 2003, Biol Philos 22:709–725, 2007; Assis and Brigandt, Evol Biol 36:248–255, 2009). This article argues that moves in this direction miss the essential disagreement between these concepts as they have been developed in the context of the debate concerning the best concept for evolutionary investigation. We should rather see these concepts employing a common fundamental methodological approach to homology, but disagreeing about how to apply the methodology effectively. Both concepts employ class reasoning, which pursues homologies as units of generalization—more precisely, as sources of reliable and relevant group-bound information in the form of shared underlying causes. The dispute can be better understood by two poles that structure such reasoning: the need for a reliable basis for projections about the causal history of shared structures, and the desire to identify homologous characters with more informative and specific causal information relevant to generalizing about evolutionary processes. Judgments in favor of one or the other in turn have affected the scope or extension of these competing homology concepts. (shrink)

The aim of this article is to detail some reservations against the beliefs, claims, or presuppositions that current essentialist natural kind concepts (including homeostatic property cluster kinds) model grouping practices in the life sciences accurately and generally. Such concepts fit reasoning into particular preconceived epistemic and semantic patterns. The ability of these patterns to fit scientific practice is often argued in support of homeostatic property cluster accounts, yet there are reasons to think that in the life sciences kind concepts exhibit (...) a diversity of grouping practices that are flattened out by conceptualizing them as natural kinds. Instead this article argues that the process of understanding grouping practices needs to start from a more neutral position independent of any ontological account. Following Love (Acta Biotheor 57:51–75, 2009) this paper suggests that typical natural kind concepts should be broached in the first place as grouping strategies that use a variety of semantic and epistemic tactics to apply group-bound information to tasks of explanation and understanding. (shrink)

The traditional practice of establishing morphological types and investigating morphological organization has found new support from evolutionary developmental biology (evo-devo), especially with respect to the notion of body plans. Despite recurring claims that typology is at odds with evolutionary thinking, evo-devo offers mechanistic explanations of the evolutionary origin, transformation, and evolvability of morphological organization. In parallel, philosophers have developed non-essentialist conceptions of natural kinds that permit kinds to exhibit variation and undergo change. This not only facilitates a construal of species (...) and higher taxa as natural kinds, but also broadens our perspective on the diversity of kinds found in biology. There are many different natural kinds relevant to the investigative and explanatory aims of evo-devo, including homologues and developmental modules. (shrink)

This article, which is intended both as a position paper in the philosophical debate on natural kinds and as the guest editorial to this thematic issue, takes up the challenge posed by Ian Hacking in his paper, “Natural Kinds: Rosy Dawn, Scholastic Twilight.” Whereas a straightforward interpretation of that paper suggests that according to Hacking the concept of natural kinds should be abandoned, both in the philosophy of science and in philosophy more generally, we suggest that an alternative and less (...) fatalistic reading is also possible. We argue that abandoning the concept of natural kinds would be premature, as it still can do important work. Our concern is with the situation in the (philosophy of the) life sciences. Against the background of this concern we attempt to set something of an agenda for future research on the topic of natural kinds in the (philosophy of the) life sciences. (shrink)