Moral Realism and Teleosemantics

William Harms has argued that if human morality is the product ofnatural selection, moral realism will follow. The thesis that hethinks allows this bridge is teleosemantics. This argument ismistaken. Even granting both premises, forms of radical moralnon-realism remain viable, since the utterance of mistaken statements(or commands) may enhance reproductive fitness.     

Mental content and evolutionary explanation

Cognitive ethology is the comparative study of animal cognition from an evolutionary perspective. As a sub-discipline of biology it shares interest in questions concerning the immediate causes and development of behavior. As a part of ethology it is also concerned with questions about the function and evolution of behavior. I examine some recent work in cognitive ethology, and I argue that the notions of mental content and representation are important to enable researchers to answer questions and state generalizations about the function and volution of behavior.I would like to thank Dorothy Cheney, Keith Donnellan, Alan Nelson, and Robert Seyfarth for their help.     

Teleosemantics and the free energy principle

Biology & Philosophy - Reconstructing ancestral species is a challenging endeavour: fossils are often scarce or enigmatic, and inferring ancestral characters based on novel molecular approaches...     

Species,essence and explanation

Michael Devitt, 2008, Devitt, 2010 has argued that species have intrinsic essences. This paper rebuts Devitt’s arguments, but in so doing it shores up the anti-essentialist consensus in two ways that have more general interest. First, species membership can be explanatory even when species have no essences; that is, Tamsin’s membership of the tiger species can explain her stripyness, without this committing us to any further claim about essential properties of tigers. Second, even the views of species that appear most congenial to essentialism—namely phenetic and genotypic cluster accounts—do not entail strong forms of intrinsic essentialism.     

Discriminating between energetic content and dietary composition as an explanation for dietary restriction effects

A reduction in dietary calories has been shown to prolong life span in a wide variety of taxa, but there has been much debate about confounding factors such as nutritional composition of the diet, or reallocation of nutrients from reduced reproduction. To disentangle the contribution of these different mechanisms to extension of life span, we study the effect of caloric restriction on longevity and fecundity in two species of sugar-feeding parasitoid wasps. They have a simple diet that consists of carbohydrates only, and they do not resorb eggs, which rules out the proposed alternative explanations for beneficial effects of caloric restriction. Two caloric restriction treatments were applied: first, dietary dilution to investigate the effect of carbohydrate concentration in the diet; and second, intermittent feeding to examine the effect of feeding frequency on longevity and fecundity. Only the dietary dilution treatment showed an effect of caloric restriction with the highest longevity recorded at 80% sucrose (w/v). No effect of dietary regime was found on fecundity. We also measured the weight increase of the parasitoids after feeding to obtain an estimate of consumption. A constant quantity of the sugar solution was consumed in all dietary dilution treatments, hence caloric intake was proportional to sucrose concentrations. Although the present study does not disqualify the relevance of nutrient composition in other species, our data unequivocally demonstrate that caloric restriction alone is sufficient to extend life span and invalidate alternative explanations.     

Endemicity biases nestedness metrics: a demonstration, explanation and solution

Nestedness is frequently investigated to understand complex patterns of species occurrences. Temperature (T) is commonly used for comparisons of nestedness of different-sized datasets. However, the assumptions made for the standardization of this metric have not been fully explored, particularly the effects of endemicity. Here we show that T incorrectly indicates an increase in nestedness with the addition of non-nested endemics to matrices that are not perfectly nested – a consequence of standardizing matrix size by the product of species and sites. This problem is common both to test matrices and to real matrices that are typically subjected to nestedness analyses. The latter are often characterized by substantial numbers of endemics and by variation in the numbers of endemics in different taxa. Standardizing by occupancy resolves this problem, which is demonstrated using a derivative of discrepancy, d1. A small modification to T, such that it standardizes matrices by occupancy, would resolve the current problems with this nestedness metric.     

Familial selection and the evolution of social behaviour re-examined

The equation for the fitness requirements for the evolution of altruism by diploid workers in haplodiploid species was derived from the model. of Scudo & Ghiselin (1975). When the benefit to a family is proportional to the number of altruists, the constraints on fitness were found to be the same as for haploid altruists in haplodiploid species and for workers of ether sex in diploid species, in contrast to the equation given by Scudo & Ghiselin (1975). With this correction, their results are now in agreement both with comparable allele frequency models and with kin selection games theory. The general condition for evolution of altruism under this model, when benefits are not necessarily proportional to the number of altruists, was also derived. The result appears to differ from games theory predictions, but this is solely because the basic assumptions are not comparable. Altruism is less likely to arise under these conditions, which are less favorable for altruism at gene frequencies above 0·33.     

Mechanisms,malfunctions and explanation in medicine

Mechanisms are a way of explaining how biological phenomena work rather than why single elements of biological systems are there. However, mechanisms are usually described as physiological entities, and little or no attention is paid to malfunction as an independent theoretical concept. On the other hand, malfunction is the main focus of interest of applied sciences such as medicine. In this paper I argue that malfunctions are parts of pathological mechanisms, which should be considered separate theoretical entities, conceptually having a priority over physiological sequences. While pathological mechanisms can be described in terms of a Cummins-like mechanistic explanation, they show some unnoticed peculiarities when compared to physiological ones. Some features of pathological mechanisms are considered, such as outcome variability, ambivalence and dependence on a range.     

Mathematical models, explanation, laws, and evolutionary biology

It is commonly agreed in the literature on laws of nature that there are at least two necessary conditions for lawhood--that a law must have empirical content and that it must be universal. The main reason offered for the requirement that laws be empirical is as follows: a priori statements are consistent with any imaginable set of observations, so they cannot be informative about the world and therefore they cannot provide explanations. However, we care about laws because we think that laws provide explanations and allow us to make predictions. Thus, if one of the functions of laws is to provide explanations and a priori propositions cannot fulfill this function, they cannot properly be viewed as laws. In this paper, I will aim to show that this argument for the claim that laws must be empirical does not work.     

Chance, explanation, and causation in evolutionary theory

Chance comes into plays at many levels of the explanation of the evolutionary process; but the unity of sense of this category is problematic. The purpose of this talk is to clarify the meaning of chance at various levels in evolutionary theory: mutations, genetic drift, genetic revolutions, ecosystems, macroevolution. Three main concepts of chance are found at these various levels: luck (popular concept), randomness (probabilistic concept), and contingency relative to a given theoretical system (epistemological concept). After identifying which concept(s) of chance fit(s) with these levels, the question is raised whether these concepts can be reduced to a smaller number, and whether chance in evolutionary theory has a subjective or an objective sense.     

Blocked and test-stimulus exposure effects in perceptual learning re-examined

Three experiments re-examined the effects of blocked or alternated exposure to the conditioning and test stimuli and the effect of simple exposure to the test stimulus, on stimulus generalization. In all experiments rats received conditioning where a compound flavor, AX, was paired with LiCl-induced illness. All rats were tested for generalization with another flavor, BX. In Experiment 1, rats that received alternating exposure to the two flavor compounds, AX and BX, prior to conditioning showed less generalization to BX than rats that received no exposure. Exposure to BX or AX alone was also somewhat effective in reducing generalization. In Experiment 2 blocked exposure to AX and BX prior to conditioning was effective in reducing generalization, as was alternated exposure, and extended exposure to BX was more effective than the other procedures. In Experiment 3, exposure to X alone prior to conditioning produced generalization equal to that produced by alternated or blocked exposure and replicated the effect of extended exposure to BX found in the previous experiment. The relevance of the results to the theories proposed by McLaren and Macintosh [Anim. Learn. Behav. 28 (2000) 211] and Hall [Q. J. Exp. Psychol. B 56 (2003) 43] is discussed.     

Evolved ethics re-examined: The theory of Robert J. Richards

Conclusion Richards's theory, then, fails on three counts. By illegitimately importing a premise from outside of the theory of evolution in order to construct a valid argument, Richards has failed to achieve his objective of deriving a moral theory exclusively from biological facts. By sliding from a causal use of ought to a moral one, Richards commits the fallacy of ambiguity. And by insisting that action from the motive of altruism is moral while claiming that an ethical theory which justifies Hitler's camps must be judged false, Richards has falsified his own ethical theory.     

Mass changes in migrating birds: the evidence for fat and protein storage re-examined

The fact that one cannot kill a bird twice makes it very difficult to determine the relative contributions of fat and non-fat components to increases in body mass before migratory flights in individual birds. Knowing the relative contributions of these components is of obvious energetic interest since fat yields about eight times as much energy as fat-free muscle tissue. Several recent studies have failed to demonstrate convincingly, due to flaws in their analyses, that fat-free mass in addition to fat is accumulated before long-distance flights. We point out that regressions of fat or the non-fat component on total body mass cannot yield reliable estimates of the composition of individual mass changes in view of inter-individual variation in structural size, reserve levels or timing of storage. We suggest that studies over time of synchronous populations or marked individuals will give better answers. A re-analysis of published data indicates the widespread existence of fat-free tissue deposition during migration, whereas in some species fat alone explained the increase in total body mass. Larger species tend to incorporate a relatively higher proportion of non-fat components when increasing in mass. However, the comparative data set is not yet of sufficient quality to allow general statements on why, and to what extent in different individuals and species, non-fat tissue in addition to fat is deposited before take-off on migratory flights.