In a previous study, using experimental metapopulations of the flour beetle, Tribolium castaneum, we investigated phase III of Wright's shifting balance process (Wade and Griesemer 1998). We experimentally modeled migration of varying amounts from demes of high mean fitness into demes of lower mean fitness (as in Wright's characterization of phase III) as well as the reciprocal (the opposite of phase III). We estimated the meta-populational heritability for this level of selection by regression of offspring deme means on the (...) weighted parental deme means.Here we develop a Punnett Square representation of the inheritance of the group mean to place our empirical findings in a conceptual context similar to Mendelian inheritance of individual traits. The comparison of Punnett Squares for individual and group inheritance shows how the latter concept can be rigorously defined and extended despite the lack of explicitly formulated, simple Mendelian laws of inheritance at the group level. Whereas Wright's phase III combines both interdemic selection and meta-populational inheritance, our formulation separates the issue of meta-populational heritability from that of interdemic selection. We use this conceptual context to discuss the controversies over the levels of selection and the units of inheritance. (shrink)
We develop an account of laboratory models, which have been central to the group selection controversy. We compare arguments for group selection in nature with Darwin's arguments for natural selection to argue that laboratory models provide important grounds for causal claims about selection. Biologists get information about causes and cause-effect relationships in the laboratory because of the special role their own causal agency plays there. They can also get information about patterns of effects and antecedent conditions in nature. But to (...) argue that some cause is actually responsible in nature, they require an inference from knowledge of causes in the laboratory context and of effects in the natural context. This process, cause detection, forms the core of an analogical argument for group selection. We discuss the differing roles of mathematical and laboratory models in constructing selective explanations at the group level and apply our discussion to the units of selection controversy to distinguish between the related problems of cause determination and evaluation of evidence. Because laboratory models are at the intersection of the two problems, their study is crucial for framing a coherent theory of explanation for evolutionary biology. (shrink)
Pezdek and Lam [Pezdek, K. & Lam, S. . What research paradigms have cognitive psychologists used to study “False memory,” and what are the implications of these choices? Consciousness and Cognition] claim that the majority of research into false memories has been misguided. Specifically, they charge that false memory scientists have been misusing the term “false memory,” relying on the wrong methodologies to study false memories, and misapplying false memory research to real world situations. We review each of these claims (...) and highlight the problems with them. We conclude that several types of false memory research have advanced our knowledge of autobiographical and recovered memories, and that future research will continue to make significant contributions to how we understand memory and memory errors. (shrink)
Two controversies exist regarding the appropriate characterization of hierarchical and adaptive evolution in natural populations. In biology, there is the Wright-Fisher controversy over the relative roles of random genetic drift, natural selection, population structure, and interdemic selection in adaptive evolution begun by Sewall Wright and Ronald Aylmer Fisher. There is also the Units of Selection debate, spanning both the biological and the philosophical literature and including the impassioned group-selection debate. Why do these two discourses exist separately, and interact relatively little? (...) We postulate that the reason for this schism can be found in the differing focus of each controversy, a deep difference itself determined by distinct general styles of scientific research guiding each discourse. That is, the Wright-Fisher debate focuses on adaptive process, and tends to be instructed by the mathematical modeling style, while the focus of the Units of Selection controversy is adaptive product, and is typically guided by the function style. The differences between the two discourses can be usefully tracked by examining their interpretations of two contested strategies for theorizing hierarchical selection: horizontal and vertical averaging. (shrink)
Current management of people with prolonged disorders of consciousness is failing patients, families and society. The causes include a general lack of concern, knowledge and expertise; a legal and professional framework which impedes timely and appropriate decision-making and/or enactment of the decision; and the exclusive focus on the patient, with no legitimate means to consider the broader consequences of healthcare decisions. This article argues that a clinical pathway based on the principles of the English Mental Capacity Act 2005 and using (...) time-limited treatment trials could greatly improve patient management and reduce stress on families. There needs to be early and continuing use of formal best interests meetings, starting between 7 and 21 days after onset of unconsciousness. The treatment options need to evolve as the clinical state and prognosis becomes more certain. A formal discussion of treatment withdrawal should occur when the upper bound of predicted recovery falls below a level the patient would have considered acceptable, and it should always be discussed when the condition is considered permanent. Any decision to stop treatment should be contingent on a formal second opinion from an independent expert who should review the clinical situation and expected prognosis, but not the best interests decision. The article also asks how, if at all, the adverse effects on the family and the resource implications of long-term care of people left in a prolonged state of unconsciousness should be incorporated in the process. (shrink)
Although epistasis is at the center of the Fisher-Wright debate, biologists not involved in the controversy are often unaware that there are actually two different formal definitions of epistasis. We compare concepts of genetic independence in the two theoretical traditions of evolutionary genetics, population genetics and quantitative genetics, and show how independence of gene action (represented by the multiplicative model of population genetics) can be different from the absence of gene interaction (represented by the linear additive model of quantitative genetics). (...) The two formulations converge with weak selection but not with strong selection or, for multiple loci, when the aggregated interaction terms are not negligible. As a result of the different formulations of gene interaction, the presence or absence of linkage disequilibrium,/D/, does not necessarily indicate the presence or absence of fitness epistasis. Indeed, linkage disequilibrium is generated in ‘additive’ models in quantitative genetics whenever two (or more) loci experience simultaneous selection. As a research strategy, it is often practical, for theoretical or experimental reasons, to minimize gene interaction by assuming independence of gene action in regard to fitness, or by assuming linear additive effects of multiple loci on a phenotype. However, minimizing the role of epistasis in theoretical investigations hinders our understanding of the origins of diversity and the evolution of complex phenotypes. (shrink)
The nature of religion -- The moral instinct -- The evolution of religious behavior -- Music, dance, and trance -- Ancestral religion -- The transformation -- The tree of religion -- Morality, trade, and trust -- The ecology of religion -- Religion and warfare -- Religion and nation -- The future of religion.
Donepezil, an acetylcholinesterase inhibitor used in the treatment of Alzheimer's disease, has been widely cited in media and bioethics literature on cognitive enhancement (CE) as having the potential to improve the cognitive ability of healthy individuals. In both literatures, this claim has been repeatedly supported by the results of a small study published by Yesavage et al. in 2002 on non-demented pilots (30-70 years old). The factors contributing to this specific interpretation of this study's results are unclear.
Gene drives are selfish genetic elements that use a variety of mechanisms to ensure they are transmitted to subsequent generations at greater than expected frequencies. Synthetic gene drives based on the clustered regularly interspersed palindromic repeats genome editing system have been proposed as a way to alter the genetic characteristics of natural populations of organisms relevant to the goals of public health, conservation, and agriculture. Here, we review the principles and potential applications of CRISPR drives, as well as means proposed (...) to prevent their uncontrolled spread. We also focus on recent work suggesting that factors such as natural genetic variation and inbreeding may represent substantial impediments to the propagation of CRISPR drives. CRISPR-based synthetic selfish genetic elements, or gene drives, have been proposed as a means by which to genetically alter natural populations to address issues in agriculture, conservation, and public health. We describe key concepts of CRISPR gene drives and limitations that must be addressed before their use in the wild. (shrink)
Engelhardt is correct in thinking that potentiality implies continuity. The central purpose of the Aristotelian notion of potency is to explain continuity, both in becoming and in generation-corruption. If one denies continuity in change, he will have little use for potentiality, at least little use for the Aristotelian types. And there are types that should not be conflated: one to account for continuity in becoming and generation, another to account for continuity of a being going from not acting to acting. (...) The first type, where something happens to a being, is called passive potency; the second type, where a being itself actively does something, is predictably called active potency. (shrink)
Against the position of professor rex martin ("the review of metaphysics," xxv, December 1971) it is argued that there is a conceptual link between disobedience and destruction of authority, As socrates argues; that socrates does not take obedience to law to be an absolute principle of action; that socrates in the two dialogues about his trial does not contradict himself on the question of obedience to the court; that socrates' argument from piety does not undermine his arguments from injury and (...) agreement. (shrink)
Eye movements are a vital part of our interaction with the world. They play a pivotal role in perception, cognition, and education. This book is unique in tracing the history of eye movement research. It shows how great strides were made in this area long before modern recording devices were available. Anyone interested in the origins of psychology and neuroscience will find much to stimulate and surprise them in this valuable new work.
The architects of punctuated equilibrium and species selection as well as more recent workers (Vrba) have narrowed the original formulation of species selection and made it dependent upon so-called emergent characters. One criticism of this narrow version is the dearth of emergent characters with a consequent diminution in the robustness of species selection as an important evolutionary process. We argue that monomorphic species characters may at times be the focus of selection and that under these circumstances selection at the organism (...) level is by-passed due to the absence of critical variance. Selection therefore shifts to the species level where variability reemerges in a clade. The absence of critical variance among organisms prevents effect macroevolution from operating. If species-wide properties are important in macroevolutionary processes, as we contend, systematists should pay more attention to their elucidation. (shrink)