Interaction Between Humans and Pigeons

Abstract

Feral pigeons are common in urban centers. This article describes the “begging” behavior of some of these pigeons in Basel and Madrid and the behavior and motivation of pigeon feeders.     

The Units of Selection Revisited: The Modules of Selection

Richard Lewontin's (1970) early work on the units of selection initiated the conceptual and theoretical investigations that have led to the hierarchical perspective on selection that has reached near consensus status today. This paper explores other aspects of his work, work on what he termed continuity and quasi-independence, that connect to contemporary explorations of modularity in development and evolution. I characterize such modules and argue that they are the true units of selection in that they are what evolution by natural selection individuates, selects among, and transforms.     

Evolution of Canine Information Processing under Conditions of Natural and Artificial Selection

The paper first argues that under conditions of domestication animals are necessarily selected (incidentally or otherwise) for (1) responsitivity to a broad band of stimuli and (2) behavioral plasticity. The consequent tractability of domestic animals is contrasted with the stimulus-boundness and response stereotypy of the fixed action patterns observed in wild animal behavior. It is suggested that this difference accounts for the differential trainability of wolves and dogs. The second section of the paper presents observational evidence that although the wolf is not very amenable to instrumental conditioning, it possesses a highly developed capacity for observational learning. It is then noted that since observational learning requires recognition of means-ends relationships this conclusion is inconsistent with the claim that wolf behavior is largely instinct-bound. Finally, these conclusions are reconciled by hypothesizing that the wolf possesses a “duplex” information-processing system, a primitive “instinctual” system that mediates basic survival responses and a more recently acquired “cognitive” system that evolved as the wolt became a group hunter. Neurobehavioral and developmental comparisons of wolf and dog suggest that these two systems have become integrated into a single scheme in the course of the dog's domestication.     

The Gentleman and the Rogue: The Collaboration Between Charles Darwin and Carl Vogt

This paper investigates the relationship between the eminent 19th-century naturalists Charles Darwin and Carl Vogt. On two separate occasions, Vogt asked Darwin for permission to translate some of the latter’s books into German, and in both cases Darwin refused. It has generally been assumed that Darwin turned down Vogt as a translator because of the latter’s reputation as a radical libertine who was extremely outspoken in his defence of scientific materialism and atheism. However, this explanation does not fit the facts, since, on closer investigation, Darwin not only gave serious consideration to engaging Vogt as the German translator of two of his books, albeit ultimately rejecting him, but he also collaborated with Vogt on the French editions of his works. In this paper we argue that this was not because Darwin was unaware of Vogt’s personality and blunt writing style; rather, Darwin seems to have decided that the benefits he would gain from their association would clearly outweigh the risk of offending some of his readers: in working with Vogt, who was not only a knowledgeable scientist but also an avowed adherent of Darwinism, Darwin could be assured of the scientific quality of the translation and of an edition that would not distort his central concepts – both of which were by no means matters of course in 19th-century translations of scientific works.     

Darwin the geologist: Between Lyell and von Buch

Upon returning from his voyage on the Beagle, Darwin prepared reports of his geological observations. Together, these reveal Darwin's approach to reasoning about geology. Darwin argued that successive terraces prove a very gradual elevation of the coast that lagoon islands show a reciprocal sinking of the oceanic floor. Hence, Darwin reinforced Lyell's uniformitarian, or steady state theory. Unlike lagoon islands, the movement of erratic boulders onto the plains is evidence of forces, which do not now exist. Darwin and Lyell attributed this movement to floating icebergs. However, mountain formation remained difficult for them to explain with reference to contemporary causes. Lyell discovered uplifts in Scandinavia, which resulted from epirogenesis, whereas mountain formation is an orogenesis, which involves both folding and uplift. Darwin was more impressed by uplift than by folds. However, when in Cordillera he saw strata overturned by masses of injected rock, proving successive periods of violence, Darwin took a position, which was closer to the plutonic theories of von Buch and Humboldt than it was to Lyell's uniformitarian views.     

Developmental Stability of DROSOPHILA MELANOGASTER under Artificial and Natural Selection in Constant and Fluctuating Environments

Populations of Drosophila melanogaster in constant 25° and fluctuating 20/29° environments showed increases in developmental stability, indicated by decreases in bilateral asymmetry of sterno-pleural chaeta number. In both environments, rates of decrease in asymmetry were greater under natural selection (control lines) than under artificial stabilizing selection. Overall mean asymmetry was greater in the fluctuating environment.—There was no evidence that decreased asymmetry was due to heterozygosity, and the decline in asymmetry was not explained by the decline in chaeta number in the lines under only natural selection. However, the decline was consistent with changes in total phenotypic variance and environmental variance.—The divergence between lines after 39 generations of selection was seen in differences in asymmetry and also in the genotype-environment interaction expressed in cross-culturing experiments.     

The Structure of Evolution by Natural Selection

We attempt a conclusive resolution of the debate over whether the principle of natural selection (PNS), especially conceived as the `principle' of the `survival of the fittest', is a tautology. This debate has been largely ignored for the past 15 years but not, we think, because it has actually been settled. We begin by describing the tautology objection, and situating the problem in the philosophical and biology literature. We then demonstrate the inadequacy of six prima facie plausible reasons for believing that the tautology debate has been satisfactorily resolved (the PNS is strictly a methodological principle; scientific theories can contain tautologies; the scope of the PNS has been reduced; theories should be understood as models and not exceptionless laws; the widespread acceptance of the propensity interpretation of fitness; and the abandonment of operationalism and verificationism). We proceed to a detailed discussion of Brandon's law (D) describing the PNS, and show that law (D) seriously misrepresents the structure of evolution by natural selection. In the final sections, we provide and defend a novel reinterpretation of the structure of the principle (or, we prefer, model) of evolution by natural selection.     

Adaptation and Natural Selection revisited

In Adaptation and Natural Selection, George C. Williams linked the distinction between group and individual adaptation with the distinction between group and individual selection. Williams’ Principle, as we will call it, says that adaptation at a level requires selection at that level. This is a necessary but not a sufficient condition; for example, group adaptation requires group selection, but the fact that group selection influences a trait’s evolution does not suffice for the resulting trait frequency to be a group adaptation. What more is required? In this paper, we describe an answer to this question that has been developed in multilevel selection theory. We also discuss an alternative framework for defining units of adaptation that violates Williams’ Principle.     

Natural Selection and Material Culture

Natural selection is the basis of all evolutionary applications in biology as well as studies of cultural process in archaeology. Natural selection is important because it allows us the tools to talk not only about variation in biological systems but also material culture that are the by-products of the human decision-making processes. In this paper, we provide a baseline of the concept of natural selection and explanatory application in evolutionary archaeology.