Function, chance and purpose in the biosphere: a critical examination of the Darwinized Gaia hypothesis.

The original Gaia hypothesis purports to explain the long-term maintenance of the Earth's habitability by proposing that the biosphere has evolved homeostatic control of environmental parameters crucial to its survival. This idea was criticized for being incompatible with core Darwinian requirements for evolution by natural selection, since the biosphere is not part of a population of entities with variation, reproduction and heredity. Recently, however, some authors have defended a 'Darwinized' version of the Gaia hypothesis.

The Significance of Mendelism for Evolutionary Theory: A Reassessment.

It is well-known that the rediscovery of Mendelian genetics at the turn of twentieth century offered Darwin's theory a much-needed lifeline, by showing how Fleeming Jenkins' famous "blending" objection could be rebutted. However, Mendelism has another fortuitous consequence for evolutionary biology that is less widely appreciated. By bequeathing the notion of allelism to biology, Mendelism shows how two difficult conceptual issues for evolutionary theory can be resolved.

Reuniting philosophy and science to advance cancer research.

Cancers rely on multiple, heterogeneous processes at different scales, pertaining to many biomedical fields. Therefore, understanding cancer is necessarily an interdisciplinary task that requires placing specialised experimental and clinical research into a broader conceptual, theoretical, and methodological framework. Without such a framework, oncology will collect piecemeal results, with scant dialogue between the different scientific communities studying cancer.

Towards evolutionary predictions: Current promises and challenges.

Evolution has traditionally been a historical and descriptive science, and predicting future evolutionary processes has long been considered impossible. However, evolutionary predictions are increasingly being developed and used in medicine, agriculture, biotechnology and conservation biology. Evolutionary predictions may be used for different purposes, such as to prepare for the future, to try and change the course of evolution or to determine how well we understand evolutionary processes.

On geometric mean fitness: a reply to Takacs and Bourrat.

In a recent paper, Takacs and Bourrat (Biol Philos 37:12, 2022) examine the use of geometric mean reproductive output as a measure of biological fitness. We welcome Takacs and Bourrat's scrutiny of a fitness definition that some philosophers have adopted uncritically. We also welcome Takacs and Bourrat's attempt to marry the philosophical literature on fitness with the biological literature on mathematical measures of fitness.

The Price equation and the causal analysis of evolutionary change.

Though the Price equation in itself is simply a statistical identity, biologists have often adopted a 'causal interpretation' of the equation, in the sense that its component terms have been supposed to correspond to distinct causal processes in evolution, such as natural selection and transmission bias. In this paper, we bring the issue of causal interpretation to the fore, by studying the conditions under which it is legitimate to read causal meaning into the Price equation. We argue that only if substantive assumptions about causal structure are made, which can be represented in the form of a causal model, can the component terms of the Price equation be interpreted as causally meaningful.

The causal meaning of Hamilton's rule.

Hamilton's original derivation of his rule for the spread of an altruistic gene (rb>c) assumed additivity of costs and benefits. Recently, it has been argued that an exact version of the rule holds under non-additive pay-offs, so long as the cost and benefit terms are suitably defined, as partial regression coefficients. However, critics have questioned both the biological significance and the causal meaning of the resulting rule.

Emergent group traits, reproduction, and levels of selection.

All group traits, "emergent" or otherwise, are ultimately dependent on the traits and behaviours of the individuals that constitute the group. Unless a process of "group reproduction" is envisaged, this means that the evolution of group traits can in principle be studied in an individualistic way, by studying the dynamics of the underlying individual traits on which they depend.

Inclusive fitness maximization: An axiomatic approach.

Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology.

Emergence, hierarchy and top-down causation in evolutionary biology.

The concept of emergence and the related notion of 'downward causation' have arisen in numerous branches of science, and have also been extensively discussed in philosophy. Here, I examine emergence and downward causation in relation to evolutionary biology. I focus on the old, but ongoing discussion in evolutionary biology over the 'levels of selection' question: which level(s) of the biological hierarchy natural selection acts at, e.

Inclusive fitness theory and eusociality.

Arising from M. A. Nowak, C.

Multilevel selection and the partitioning of covariance: a comparison of three approaches.

Where the evolution of a trait is affected by selection at more than one hierarchical level, it is often useful to compare the magnitude of selection at each level by asking how much of the total evolutionary change is attributable to each level of selection. Three statistical partitioning techniques, each designed to answer this question, are compared, in relation to a simple multilevel selection model in which a trait's evolution is affected by both individual and group selection. None of the three techniques is wholly satisfactory: one implies that group selection can operate even if individual fitness is determined by individual phenotype alone, whereas the other two imply that group selection can operate even if there is no variance in group fitness.