Living organisms are caught between a hammer and an anvil, evolutionarily speaking. On the one hand, they need to buffer the influences of genetic mutations and environmental stresses if they are to develop normally and maintain a coherent and functional form. On the other, stabiliz- ing one’s development too much may mean not being able to respond at all to changes in the environment and starting down the primrose path to extinction. On page 618 of this issue, Queitsch et al.1 (...) propose that, in plants, the balance between stability and the potential for change is made possible in part through a protein involved in ‘heat- shock responses’ in a wide variety of species, from plants to insects. (shrink)

We consider, from a physical perspective, the case where the interface between an organism and its environment becomes large enough that it acts as a buffer regulating their matter and energy exchanges. We illustrate the physiological and evolutionary role of buffers through the example of lungfish estivation. Then we ponder the relevance of buffers of this kind to the quest for a general definition of concepts like niche construction, the extended phenotype, and related ones, whose meaning is (...) conveyed at present mostly through particular examples. Finally, we comment on the potential significance of buffers to organism—environment codetermination in the sense originally suggested by Lewontin. (shrink)

DNA sequence variation is abundant in wild populations. While molecular biologists use genetically homogeneous strains of model organisms to avoid this variation, evolutionary biologists embrace genetic variation as the material of evolution since heritable differences in fitness drive evolutionary change. Yet, the relationship between the phenotypic variation affecting fitness and the genotypic variation producing it is complex. Genetic buffering mechanisms modify this relationship by concealing the effects of genetic and environmental variation on phenotype. Genetic buffering allows the build-up (...) and storage of genetic variation in phenotypically normal populations. When buffering breaks down, thresholds governing the expression of previously silent variation are crossed. At these thresholds, phenotypic differences suddenly appear and are available for selection. Thus, buffering mechanisms modulate evolution and regulate a balance between evolutionary stasis and change. Recent work provides a glimpse of the molecular details governing some types of genetic buffering. BioEssays 22:1095–1105, 2000. © 2000 John Wiley & Sons, Inc. (shrink)

The emergence of new biological traits is landmarks of evolutionary progress. However, when, how, and why do they appear? We propose a universal mechanism, a Buffering Mechanism of Evolution to understand these questions. We speculate that all organisms possess this potential buffer capacity. This capacity would be triggered by the pressures, natural or artificial, to express the intrinsic potential variants. The potential buffer capacity of the organism increases for further selections as evolutionary progress occurs. The higher the (...) class='Hi'>evolutionary level of the organism, the greater the potential buffer capacity, and importantly, the buffer capacity versus the pressures of selections will result. However, when the pressures are far more than the potential capacity of the targets, the natural or artificial pressures then compromise the genetic buffering system resulting in possible species extinction if the emergence of new traits fails. (shrink)

Pregnancy is thought to be a metabolically very expensive endeavor, yet investigations have produced inconsistent results concerning the responsiveness of human birth weight to maternal nutritional stress or nutritional intervention. These findings have led some researchers to conclude that fetal growth is strongly buffered against fluctuations in maternal energy balance, making the fetus in effect a “nearly perfect parasite.” This buffering would appear to be a reasonable adaptive response given the high risk of morbidity and mortality associated with low birth (...) weight. However, a life-history approach leads to the prediction that maternal investment strategies in pregnancy should be geared toward maximizing lifetime reproductive success rather than simply the success of the current pregnancy, and by extension that maternal investment strategies should vary with reproductive value. The physiology of human pregnancy in fact appears to include a number of mechanisms that protect maternal energy resources from diversion to the fetus and preserve them for future reproductive events. These mechanisms include adjustment of blood flow to the uterus and perhaps minor adjustments in gestation length, although evidence for the latter is scant. Suggestions are made for ways of investigating these maternal options. (shrink)

This article reviews the effects of malnutrition on early brain development using data generated from animal experiments and human clinical studies. Three related processes, each with their own functional consequences, are implicated in the alteration of brain development. (1) Maternal undernutrition at the start of pregnancy results in reduced transfer of nutrients across the placenta, allowing the conservation of effort for future reproductive episodes. (2) Differential allocation to growing organs by the fetus in response to nutritional stress spares the brain (...) to a large though still limited degree, reflecting the organ’s relative contribution to survival and reproductive success. (3) Prenatal malnutrition disrupts developing neurotransmitter systems, which results in the expression of specific cognitive and affective traits. It is argued that the increasing size and therefore cost of the brain, in conjunction with increasing ecological instability and marginality, reinforced selection for maternally controlled growth suppression of offspring, reallocation of organ growth rates by offspring, and behavioral changes related to development of neurotransmitter systems. (shrink)

Embryonic development combines paradoxical properties: it has great precision, it is usually conducted at breakneck speed and it is flexible on relatively short evolutionary time scales, particularly at early stages. While these features appear mutually exclusive, we consider how they may be reconciled by the properties of key early regulatory networks. We illustrate these ideas with the network that controls development of endoderm progenitors. We argue that this network enables precision because of its intrinsic stability, self propagation and dependence (...) on signalling. The network enables high developmental speed because it is rapidly established by maternal inputs at multiple points. In turn these properties confer flexibility on an evolutionary time scale because they can be initiated in many ways, while buffering essential progenitor cell populations against changes in their embryonic environment on both evolutionary and developmental time scales. Although stable, these networks must be capable of rapid dissolution as cell differentiation progresses. While we focus on the core early endodermal network of vertebrates, we argue that these properties are likely to be general in early embryonic stem cell populations, such as mammalian ES cells. BioEssays 30:757–765, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

Recent work on the heat-shock protein Hsp90 by Rutherford and Lindquist (1998) has been included among the pieces of evidence taken to show the essential role of developmental processes in evolution; Hsp90 acts as a buffer against phenotypic variation, allowing genotypic variation to build. When the buffering capacity of Hsp90 is altered (e.g., in nature, by mutation or environmental stress), the genetic variation is "revealed," manifesting itself as phenotypic variation. This phenomenon raises questions about the genetic variation before and after (...) what I will call a "revelation event": Is it neutral, nearly neutral, or non-neutral (i.e., strongly deleterious or strongly advantageous)? Moreover, what kinds of evolutionary processes do we take to be at work? Rutherford and Lindquist (1998) focus on the implications of non-neutral variation and selection. Later work by Queitsch, Sangster, and Lindquist (2002) and Sangster, Lindquist, and Queitsch (2004) raises the possibility that Hsp90 buffering may play the role that was played by drift in Sewall Wright's shifting balance model, permitting transition from one adaptive peak to another. However, Ohta (2002) suggests that much of this variation may be nearly neutral, which in turn, would imply a strong role for drift as well as selection. The primary goal of this paper is to illuminate the alternative scenarios and the processes operating in each. At the end, I raise the possibility of a synthesis between evo-devo and nearly neutral evolution. (shrink)

The calcium signals regulate the production and secretion of many signaling molecules like inositol trisphosphate ( $$IP_{3}$$ ) and adenosine triphosphate (ATP) in various cells including pancreatic $$\beta$$ -cells. The calcium signaling mechanisms regulating $$IP_{3}$$, ATP and insulin responsible for various functions of $$\beta$$ -cells are still not well understood. Any disturbance in these mechanisms can alter the functions of $$\beta$$ -cells leading to diabetes and metabolic disorders. Therefore, a mathematical model is proposed by incorporating the reaction-diffusion equation for calcium (...) dynamics and a system of first-order differential equations for $$IP_{3}$$, ATP-production and insulin secretion with initial and boundary conditions. The model incorporates the temporal dependence of $$IP_{3}$$ -production and degradation, ATP production and insulin secretion on calcium dynamics in a $$\beta$$ -cell. The piecewise linear finite element method has been used for the spatial dimension and the Crank-Nicolson scheme for the temporal dimension to obtain numerical results. The effect of changes in source influxes and buffers on calcium dynamics and production of $$IP_{3}$$, ATP and insulin levels in a $$\beta$$ -cell has been analyzed. It is concluded that the dysfunction of source influx and buffers can cause significant variations in calcium levels and dysregulation of $$IP_{3}$$, ATP and insulin production, which can lead to various metabolic disorders, diabetes, obesity, etc. The proposed model provides crucial information about the changes in mechanisms of calcium dynamics causing proportionate disturbances in $$IP_3$$, ATP and insulin levels in pancreatic cells, which can be helpful for devising protocols for diagnosis and treatment of various metabolic diseases. (shrink)

The origin of novel traits is what draws many to evolutionary biology, yet our understanding of the mechanisms that underlie the genesis of novelty remains limited. Here I review definitions of novelty including its relationship to homology. I then discuss how ontogenetic perspectives may allow us to move beyond current roadblocks in our understanding of the mechanics of innovation. Specifically, I explore the roles of canalization, plasticity and threshold responses during development in generating a reservoir of cryptic genetic variation (...) free to drift and accumulate in natural populations. Environmental or genetic perturbations that exceed the buffering capacity of development can then release this variation, and, through evolution by genetic accommodation, result in rapid diversification, recurrence of lost phenotypes as well as the origins of novel features. I conclude that, in our quest to understand the nature of innovation, the nature of development deserves to take center stage. BioEssays 30:432–447, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

The phenomenon of ‘canalization’ ‐ the genetic capacity to buffer developmental pathways against mutational or environmental perturbations ‐ was first characterized in the late 1930s and early 1940s. Despite enormous subsequent progress in understanding the nature of the genetic material and the molecular basis of gene expression, there have been few attempts to interpret the classical work on canalization in molecular genetic terms. Some recent findings, however, bear on one form of canalization, ‘genetic canalization’, the stabilization of development against mutational (...) effects. These data indicate that co‐expressed paralogous genes can function as mutual ‘back‐up’ elements in developmental processes. Paralogues, however, are far from the only basis of canalization: other genetic sources can be readily envisaged and some of these are described here. The evolutionary questions about genetic canalization and the mechanistic questions about developmental instability that still need to be addressed are also briefly discussed. (shrink)

The structuring of our environment to provide cues and reminders for ourselves is common: We leave notes on the fridge, we have a particular place for our keys where we deposit them, making them easy to find. We alter our world to streamline our cognitive tasks. But how did hominins gain this capacity? What pushed our ancestors to structure their physical environment in ways that buffered thinking and began the process of using the world cognitively? I argue that the capacity (...) to engage in these behaviours is a by-product of increased tool investment and tool curation, which in turn was necessary because of increasingly heterogeneous environments. The minute tools are carried and cared for, they begin to undergo selection for added functions, becoming available as cognitive primers and as signals. I explore the trajectory of this co-evolutionary feedback loop of hominins and their tools, and demonstrate the role tools have in shaping our thinking. (shrink)

Integrative explanations of why obesity is more prevalent in some sectors of the human population than others are lacking. Here, we outline and evaluate one candidate explanation, the insurance hypothesis. The IH is rooted in adaptive evolutionary thinking: The function of storing fat is to provide a buffer against shortfall in the food supply. Thus, individuals should store more fat when they receive cues that access to food is uncertain. Applied to humans, this implies that an important proximate driver (...) of obesity should be food insecurity rather than food abundance per se. We integrate several distinct lines of theory and evidence that bear on this hypothesis. We present a theoretical model that shows it is optimal to store more fat when food access is uncertain, and we review the experimental literature from non-human animals showing that fat reserves increase when access to food is restricted. We provide a meta-analysis of 125 epidemiological studies of the association between perceived food insecurity and high body weight in humans. There is a robust positive association, but it is restricted to adult women in high-income countries. We explore why this could be in light of the IH and our theoretical model. We conclude that although the IH alone cannot explain the distribution of obesity in the human population, it may represent a very important component of a pluralistic explanation. We also discuss insights it may offer into the developmental origins of obesity, dieting-induced weight gain, and anorexia nervosa. (shrink)

Plan-ahead becomes necessary for those movements which are over-and-done in less time than it takes for the feedback loop to operate. Natural selection for one of the ballistic movements (hammering, clubbing, and throwing) could evolve a plan-ahead serial buffer for hand-arm commands that would benefit the other ballistic movements as well. This same circuitry may also sequence other muscles (children learning handwriting often screw up their faces and tongues) and so novel oral-facial sequences may also benefit (as might kicking and (...) dancing). An elaborated version of the sequencer may constitute a Darwin Machine that spins scenarios, evolves sentences, and facilitates insight by offline simulation. An example is given of an evolutionary scenario from an apelike ancestor, demonstrating the transition behaviors and growth curve considerations that any such theory needs to have; this particular scenario (involving throwing improvements) also suggests an explanation for the puzzling design of the Acheulean "handaxe.". (shrink)

Human evolution has been punctuated by climate anomalies, structuring environments, deadly infections, and altering landscapes. How well humans adapted to these new circumstances had direct effects on fitness and survival. Here, how the gut microbiome could have contributed to human evolutionary success through contributions to host nutritional buffering and infectious disease resistance is reviewed. How changes in human genetics, diet, disease exposure, and social environments almost certainly altered microbial community composition is also explored. Emerging research points to the microbiome (...) as a key player in host responses to environmental change. Therefore, the reciprocal interactions between humans and their microbes are likely to have shaped human patterns of local adaptation throughout our shared evolutionary history. Recent alterations in human lifestyle, however, are altering human microbiomes in unprecedented ways. The consequences of interrupted host–microbe relationships for human adaptive potential in the future are unknown. (shrink)

Health care reform in the United States and United Kingdom has resulted in the cross-fertilization of policy. The “new” health care models adopted by the two jurisdictions utilize free market principles for reasons of quality, efficiency, and cost, but also feature characteristics of a state-run model, through the provision of a safety net for citizens and a buffer against the commodification of health. In this sense, the health care systems of the US and UK are more congruent than they were. (...) Here we identify two distinct narratives that emerge from health care reform undertaken in these jurisdictions. The “revolutionary” narrative views the reforms as fundamental change whilst the “evolutionary” narrative accepts them as natural development. We argue that neither the revolutionary nor the evolutionary narrative adequately characterizes the reforms undertaken in health care because neither takes sufficient account of the broader setting in which reform has occurred. In seeking to examine and explain the jurisdictions' apparent drive to the middle, we propose a distinctive evolutionary narrative, that of “convergence,” which, as well as adopting a less parochial perspective on developments in health care policy and provision, also situates the reforms politically, constitutionally, and comparatively. (shrink)

Laland et al. suggest that as a specific evolutionary force niche construction has entailed the encephalization of the brain. While not denying rapid co-evolution of brain traits and abilities with niches and cultures, I argue that encephalization reflects a classical genetic buffer system allowing rapid evolutionary adaptation independent of the nature of the selective pressure.

In order to make an attempt at grouping the various aspects of brain functional imaging (fMRI, MRS, EEG-MEG, ...) within a coherent frame, we implemented a model consisting of a system of differential equations, that includes: (1) sodium membrane transport, (2) Na/K ATPase, (3) neuronal energy metabolism (i.e. glycolysis, buffering effect of phosphocreatine, and mitochondrial respiration), (4) blood-brain barrier exchanges and (5) brain hemodynamics, all the processes which are involved in the activation of brain areas. We assumed that the correlation (...) between brain activation and metabolism could be due to either changes in the concentrations of ATP and ADP following activation of Na/K ATPase that result from the changes in ion concentrations, or the involvement, in different phases of metabolism, of a second messenger such as calcium. In this article, we show how this type of model enables interpretation of MRS and fMRI published data that were obtained during prolonged stimulations. (shrink)

It is commonly suggested that evolutionary considerations generate an epistemological challenge for moral realism. At first approximation, the challenge for the moral realist is to explain our having many true moral beliefs, given that those beliefs are the products of evolutionary forces that would be indifferent to the moral truth. An important question surrounding this challenge is the extent to which it generalizes. In particular, it is of interest whether the Evolutionary Challenge for moral realism is equally (...) a challenge for mathematical realism. It is widely thought not to be. In this paper, I argue that the Evolutionary Challenge for moral realism is equally a challenge for mathematical realism. Along the way, I substantially clarify the Evolutionary Challenge, discuss its relation to more familiar epistemological challenges, and broach the problem of moral disagreement. The paper should be of interest to ethicists because it places pressure on anyone who rejects moral realism on the basis of the Evolutionary Challenge to reject mathematical realism as well. And the paper should be of interest to philosophers of mathematics because it presents a new epistemological challenge for mathematical realism that bears, I argue, no simple relation to Paul Benacerraf's familiar challenge. (shrink)

Moral realism is often taken to have common sense and initial appearances on its side. Indeed, by some lights, common sense and initial appearances underlie all the central positive arguments for moral realism. We offer a kind of debunking argument, taking aim at realism’s common sense standing. Our argument differs from familiar debunking moves both in its empirical assumptions and in how it targets the realist position. We argue that if natural selection explains the objective phenomenology of moral deliberation and (...) judgement, then this undermines arguments from that phenomenology. This results in a simpler, and in some ways more direct, challenge to realism. It is also less vulnerable to the main objections that have been leveled against such arguments. If accepted, our conclusion should make a real difference to the dialectic in this area. It means that neither realism nor its denial is the default, to-be-refuted, position. (shrink)

I examine the relationship between evolutionary definitions of altruism that are based on fitness effects and psychological definitions that are based on the motives of the actor. I show that evolutionary altruism can be motivated by proximate mechanisms that are psychologically either altruistic or selfish. I also show that evolutionary definitions do rely upon motives as a metaphor in which the outcome of natural selection is compared to the decisions of a psychologically selfish (or altruistic) individual. Ignoring (...) the precise nature of both psychological and evolutionary definitions has obscured many important issues, including the biological roots of psychological altruism. (shrink)

In this systematic introduction to the philosophy of Charles S. Peirce, the author focuses on four of Peirce's fundamental conceptions: pragmatism and Peirce's development of it into what he called 'pragmaticism'; his theory of signs; his phenomenology; and his theory that continuity is of prime importance for philosophy. He argues that at the centre of Peirce's philosophical project is a unique form of metaphysical realism, whereby continuity and evolutionary change are both necessary for our understanding of experience. In his (...) final chapter Professor Hausman applies this version of realism to contemporary controversies between anti-realists and anti–idealists. Peirce's views are compared to those of such contemporary figures as Davidson, Putnam, and Rorty. The book will be of particular interest to philosophers concerned with American philosophy and current debates on realism as well as linguists working in semiotics. (shrink)

Growing out of concerns for environment-development interlinkages expressed at the United Nations Conference on the Human Environment, 1972, this volume is a compilation of edited versions of statements made at that conference and at the ...

Integrating affective events theory, work-family compensation, and moral balance theory, the present study proposes a model that examines how and when abusive supervisory behavior is related to employees’ deviant behavior toward their supervisor. Using a diary method that involved two surveys per day over two weeks, we found support for our model based on 707 daily observations from 130 employees. Specifically, anger toward one’s supervisor mediated the relationship between abusive supervisory behavior and deviant behavior toward one’s supervisor. In addition, the (...) degree to which employees engaged in deviant behavior toward their supervisor depended on their prior-day deviant behavior toward their family. When employees engaged in lower prior-day deviant behavior toward their family, anger toward their supervisor was positively related to subsequent deviant behavior toward their supervisor. In contrast, when employees had higher prior-day deviant behavior toward their family, the relationship between anger toward their supervisor and deviant behavior toward their supervisor was weaker. We conclude by discussing the implications of our findings for research on abusive supervision, work-family interface, and moral balance theory. (shrink)

In this paper I want to clarify what biologists are talking about when they talk about the evolution of altruism. I’ll begin by saying something about the common sense concept. This familiar idea I’ll call ‘vernacular altruism.’ One point of doing this is to make it devastatingly obvious that the common sense concept is very different from the concept as it’s used in evolutionary theory. After that preliminary, I’ll describe some features of the evolutionary concept. Then I’ll conclude (...) by briefly considering what explanatory relation might obtain between vernacular altruism and evolutionary altruism. Although the points I’ll make are rather elementary ones, their interest is not restricted to those who have never heard of the evolutionary problem. The reason for this is that there is some amount of confusion about evolutionary altruism among evolutionary biologists themselves. (shrink)

Many philosophers have asserted that evolutionary theory is unfalsifiable. In this paper I refute these assertions by detailing some falsifiable predictions of the theory and the evidence used to test them. I then analyze both these predictions and evidence cited to support assertions of unfalsifiability in order to show both what type of predictions are possible and why it has been so difficult to spot them. The conclusion is that the apparent logical peculiarity of evolutionary theory is not (...) a property of evolutionary theory; it is a property of our human-sized perspective on evolutionary theory. (shrink)

Despite their divergent metaphysical assumptions, Reformed and evolutionary epistemologists have converged on the notion of proper basicality. Where Reformed epistemologists appeal to God, who has designed the mind in such a way that it successfully aims at the truth, evolutionary epistemologists appeal to natural selection as a mechanism that favors truth-preserving cognitive capacities. This paper investigates whether Reformed and evolutionary epistemological accounts of theistic belief are compatible. We will argue that their chief incompatibility lies in the noetic (...) effects of sin and what may be termed the noetic effects of evolution, systematic tendencies wherein human cognitive faculties go awry. We propose a reconceptualization of the noetic effects of sin to mitigate this tension. (shrink)

Rom Harré criticizes critical realism for ascribing causal powers to social structures, arguing that it is human individuals, and not social structures, that possess causal powers, and that a false conception of structural causation undermines the emancipatory potential of critical realism. I argue that an interpretation of the category of process as the spatio-temporalization of the category of structure, which underpins much evolutionary theory, provides the conceptual tools to explain how the critical realist transformational model of social activity can (...) escape from Harré’s criticism, leading to a general conception of social development within which various types of evolutionary processes can be identified as particular cases. I then argue that Tony Lawson’s PVRS model provides an evolutionary perspective that enables the conceptualization of coercive power as selective pressure. (shrink)

Expressivism is a blossoming meta-semantic framework sometimes relying on what Carter and Chrisman call “the core expressivist maneuver.” That is, instead of asking about the nature of a certain kind of value, we should be asking about the nature of the value judgment in question. According to expressivists, this question substitution opens theoretical space for the elegant, economical, and explanatorily powerful expressivist treatment of the relevant domain. I argue, however, that experimental work in cognitive psychology can shed light on how (...) the core expressivist maneuver operates at the cognitive level and that this: raises worries about the aptness of the expressivist question substitution and supports an evolutionary debunking argument against expressivism. Since evolutionary debunking arguments are usually run in favor of expressivism, this creates an obvious puzzle for expressivists. I wrap up by briefly responding to the objection that the debunking argument against expressivism overgeneralizes and, therefore, should be rejected. (shrink)

Accounts of the evolutionary past have as much in common with works of narrative history as they do with works of science. Awareness of the narrative character of evolutionary writing leads to the discovery of a host of fascinating and hitherto unrecognized problems in the representation of evolutionary history, problems associated with the writing of narrative. These problems include selective attention, narrative perspective, foregrounding and backgrounding, differential resolution, and the establishment of a canon of important events. The (...) narrative aspects of evolutionary writing, however, which promote linearity and cohesiveness in conventional stories, conflict with the underlying chronicle of evolution, which is not linear, but branched, and which does not cohere, but diverges. The impulse to narrate is so great, however, and is so strongly reinforced by traditional schemes of taxonomic attention, that natural historians have more often abandoned the diverging tree than they have abandoned the narrative mode of representation. If we are to understand the true nature of the evolutionary past then we must adopt “tree thinking”, and develop new and creative ways, both narrative and non-narrative, of telling the history of life. (shrink)

Mutational robustness facilitates evolutionary innovations. Gene duplications are unique kinds of mutations, in that they generally increase such robustness. The frequent association of gene duplications in regulatory networks with evolutionary innovation is thus a special case of a general mechanism linking innovation to robustness. The potential power of this mechanism to promote evolutionary innovations on large time scales is illustrated here with several examples. These include the role of gene duplications in the vertebrate radiation, flowering plant evolution (...) and heart development, which encompass some of the most striking innovations in the evolution of life. BioEssays 30:367–373, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

This book is an in-depth treatment of Darwinian evolutionism and its applicability to the investigation of the archaeological record. The authors explain the unique position that this kind of evolutionism holds in science and how it bears on any attempt to explain change over time in the organic world, demonstrate commonalities between archaeology and paleobiology, and explain the principles, methods, and techniques - the systematics - inherent in the approach.

In Romans 5, St. Paul claims that death came into the world through Adam's sin. Many have taken this to foist on us a fundamentalist reading of Genesis. If death is the result of human sin, then, apparently, there cannot have been death in the world prior to human sin. This, however, is inconsistent with contemporary evolutionary biology, which requires that death predates the existence of modern humans. Although the relationship between Romans 5, Genesis, and contemporary science has been (...) much discussed—often with goal of dissipating the idea that the two are in conflict—the specific issue of death entering the world through sin has remained difficult to resolve. I argue that the Eastern Orthodox tradition has the resources to respect both Romans 5 and contemporary science. Appealing to a broadly Irenaean notion of soul‐making, and to the idea of theosis, opens up space for an understanding of these passages that is both scientifically informed and Orthodox. (shrink)

Evolutionary psychologists attempt to infer our evolved psychology from the selection pressures present in our ancestral environments. Their use of this inference strategy—often called “adaptive thinking”—is thought to be justified by way of appeal to a rather modest form of adaptationism, according to which the mind's adaptive complexity reveals it to be a product of selection. I argue, on the contrary, that the mind's being an adaptation is only a necessary and not a sufficient condition for the validity of (...) adaptive thinking, and that evolutionary psychology's predictive project is in fact committed to an extremely strong and highly implausible form of adaptationism. According to this “strong adaptationism,” the macroevolutionary trajectory of a population is determined by, and therefore predictable on the basis of, the selection pressures acting upon it. Not only is this form of adaptationism prima facie highly implausible, it requires making a number of naïve and likely false assumptions concerning the nature of heritable phenotypic variation in natural populations. In particular, it assumes that phenotypic variation is inevitably small in its extent, unbiased in its direction, and copious in its quantity. Because it is unlikely that these conditions obtain as a general rule, and even more unlikely that they obtained in early human populations, I conclude that there is little reason to believe that adaptive thinking can be used to infer the current structure of our minds from evidence of past selection pressures. (shrink)