Methodological problems in evolutionary biology

One of the major criticisms of optimal foraging theory (OFT) is that it is not testable. In discussions of this criticism opposing parties have confused methodological concepts and used meaningless biological concepts. In this paper we discuss such misunderstandings and show that OFr has an empirically testable, and even well-confirmed, general core theory. One of our main conclusions is that specific model testing should not be aimed at proving optimality, but rather at identifying the context in which certain types of behaviour are optimal. To do this, it is necessary to be aware of the assumptions made in testing a model. The assumptions that are explicitly stated in the literature up to now do not completely cover the actual assumptions made in testing OFT models in practice. We present a more comprehensive set of assumptions. Although all the assumptions play a role in testing models, they are not of equal status. Crucial assumptions concern constraints and the relation between fitness and currency. Therefore, it is essential to make such assumptions testable in practice. We show that a more explicit relationship between OFT modelling and evolutionary theory can help with this. Specifically, phylogeny reconstruction and population dynamic modelling can and should be used to formulate assumptions concerning constraints and currencies.     

Methodological problems in evolutionary biology VIII. Biology and culture

Biology cannot accommodate all aspects of culture. Aspects of culture that a biological approach can take into account can be covered by the biological categories of phenotype and environment. There is no need to treat culture as a separate category. Attempts to elaborate biological explanations of cultural variation will meet with success only if biologists expand theories of development, and integrate them in evolutionary biology. The alternative — elaborating the idea of so-called cultural inheritance — makes little sense from a biological point of view.     

Methodological problems in evolutionary biology VI. The force of evolutionary epistemology

Evolutionary epistemology takes various forms. As a philosophical discipline, it may use analogies by borrowing concepts from evolutionary biology to establish new foundations. This is not a very successful enterprise because the analogies involved are so weak that they hardly have explanatory force. It may also veil itself with the garbs of biology. Proponents of this strategy have only produced irrelevant theories by transforming epistemology's concepts beyond recognition. Sensible theories about knowledge and biology should presuppose that various long-standing problems concerning relations between the mental and the physical are solved. Such problems are wrongly disregarded by evolutionary epistemologists.     

Methodological problems in evolutionary biology VII. The species plague

Various philosophers and evolutionary biologists have recently defended the thesis that species are individuals rather than sets. A decade of debates, however, did not suffice to settle the matter. Conceptual analysis shows that many of the key terms involved (individuation, evolutionary species, spatiotemporal restrictedness, individual) are ambiguous. Current disagreements should dissolve once this is recognized. Explication of the concepts involved leads to new programs for philosophical research. It could also help biology by showing how extant controversies concerning evolution may have conceptual rather than factual roots.     

Methodological problems in evolutionary biology V. The import of supervenience

Rosenberg has rightly argued that fitness is supervenient. But he has wrongly assumed that this makes The fittest survive nontautologous. Supervenience makes strict reduction impossible. It sheds light on disputes concerning the testability of evolutionary theory.     

Methodological problems in evolutionary biology III. Selection and levels of organization

Apparently factual disagreement on the level(s) at which selection operates often results from different interpretations of the term selection. Attempts to resolve terminological problems must come to grips with a dilemma: a narrow interpretation of selection may lead to a restricted view on evolution; a broader, less precise, definition may wrongly suggest that selection is the centre of a unified, integrated theory of evolution. Different concepts of selection, therefore, should carefully be kept apart.     

Methodological problems in evolutionary biology II. Appraisal of arguments against adaptationism

Methodological analysis shows that the concepts of fitness and adaptation are more complex than the literature suggests. Various arguments against ‘adaptationism’ are inadequate since they are couched in terms of unduly simplistic notions.     

Methodological problems in evolutionary biology IV. Stress and stress tolerance,an excercise in definitions

Grime (1979) in a recently developed theory distinguished three basic plant strategies: stress tolerance,ruderality and competition. He relates them to environments characterized in terms of stress and disturbance. Classifications of strategies and environments both are ultimately defined in terms of production. This tends to make the theory tautological. If the theory is to make sense, environments had better be defined in independent terms.     

Methodological problems of the relation of thermodynamics and biology

Methodological problems are considered on the relation of thermodynamic principles in systems far from being equilibrium and processes of biological evolution. Attention is paid that these problems are sometimes erroneously interpreted from the standpoint of reducing biology to physics and chemistry. The analysis of the theories under study shows that they reveal concretely the dialectics of biology reducibility and irreducibility to physics and chemistry. A conclusion is made that the notion of "submission of lower forms of the matter to higher ones" which is insufficiently studied in dialectics may be revealed by means of notions of lower forms regulation and control by higher ones.     

Beyond Arabidopsis. Translational biology meets evolutionary developmental biology

Developmental processes shape plant morphologies, which constitute important adaptive traits selected for during evolution. Identifying the genes that act in developmental pathways and determining how they are modified during evolution is the focus of the field of evolutionary developmental biology, or evo-devo. Knowledge of genetic pathways in the plant model Arabidopsis serves as the starting point for investigating how the toolkit of developmental pathways has been used and reused to form different plant body plans. One productive approach is to identify genes in other species that are orthologous to genes known to control developmental pathways in Arabidopsis and then determine what changes have occurred in the protein coding sequence or in the gene's expression to produce an altered morphology. A second approach relies on natural variation among wild populations or crop plants. Natural variation can be exploited to identify quantitative trait loci that underlie important developmental traits and, thus, define those genes that are responsible for adaptive changes. The possibility of applying comparative genomics approaches to Arabidopsis and related species promises profound new insights into the interplay of evolution and development.     

Phylogeny and evolutionary biology

The phylogenetic system of Hennig, which was designed for classification of synchronous organisms, has only been adapted secondarily to total reconstruction of phylogeny. All fields of fundamental biology are related to the development of evolutionary theory. A better understanding of the origin of life requires new concepts of the historical geology of prebiological environment and new concepts of molecular genetics and biochemistry concerning ribonucleic acids as the initial units for the origin of life.     

Iconometrographics in evolutionary biology

The essential dialogue between Apollinian and Dionysiac poles required for the advance of music and art was likened to the scientific debate between «justifiers» and «innovators». The use of ratios and simple algorithms was indicted as being retrogressive in terms of modern microcomputer technology and iconometrographic models. Three examples were used to illustrate the approach in the resolution of complex data sets comparing samples: (1) 45,XO with a 46,XY controls, (2) sexual dimorphism in young adults and (3) Black and White Olympic athletes. The iconometrographic approach was proposed as a primary orientation in human biology, particularly in secular trend studies concerned with the recognition and assessment of complex evolutionary trends.     

Functional morphology and evolutionary biology

In this study the relationship between functional morpholoy and evolutionary biology is analysed by confronting the main concepts in both disciplines.Rather than only discussing this connection theoretically, the analysis is carried out by introducing important practical and experimental studies, which use aspects from both disciplines. The mentioned investigations are methodologically analysed and the consequences for extensions of the relationship are worked out. It can be shown that both disciplines have a large domain of their own and also share a large common ground. Many disagreements among evolutionary biologists can be reduced to differences in general philosophy (idealism vs. realism), selection of phenomenona (structure vs. function), definition of concepts (natural selection) and the position of the concept theory as an explaining factor (neutralists vs. selectionists, random variation, determinate selection, etc.).The significance of functional morphology for evolutionary biology, and vice versa depends on these differences. For a neo-Darwinian evolutionary theory, contributions from functional and ecological morphology are indispensable. Of ultimate importance are the notions of internal selection and constraints in the constructions determining further development. In this context the concepts of random variation and natural selection need more detailed definition.The study ends with a recommendation for future research founded in a system-theoretical or structuralistic conception.     

Explanatory pluralism in evolutionary biology

The ontological dependence of one domain on another is compatible with the explanatory autonomy of the less basic domain. That autonomy results from the fact that the relationship between two domains can be very complex. In this paper I distinguish two different types of complexity, two ways the relationship between domains can fail to be transparent, both of which are relevant to evolutionary biology. Sometimes high level explanations preserve a certain type of causal or counterfactual information which would be lost at the lower level; I argue that this is central to the proper understanding of the adaptationist program. Sometimes high level kinds are multiply realised by lower level kinds: I argue that this is central to the understanding of macroevolution.     

Chance as an explanatory factor in evolutionary biology.

Darwinian evolutionary biology has often been criticized for appealing to the notion of 'chance' in its explanations. According to some critics, such appeals exhibit the explanatory poverty of evolutionary theory. In response, defenders of Darwinism sometimes downplay the importance of 'chance' in evolution. I believe that both of these approaches are mistaken. The main thesis of this paper is that the term 'chance' encompasses a number of distinct concepts, and that at least some of these concepts serve essential explanatory functions in evolutionary biology. This claim is defended by way of an historical survey of the major concepts of 'chance' in the history of evolutionary biology, especially the concepts used by Jean Baptiste Lamarck, Charles Darwin, and Sewall Wright. An examination of their biologies shows how the concepts of 'chance' used cohere with their major scientific objectives and methods. These concepts survive and continue to function as important explanatory factors in contemporary evolutionary biology. Examples of such usage are given, and the explanatory status of 'chance' assessed.