All disciplines must define their basic units and core processes. In evolutionary biology, the core process is natural selection and the basic unit of selection and adaptation is the individual. To operationalize the theory of natural selection we must count individuals, as they are the bearers of fitness. While canonical individuals have often been taken to be multicellular organisms, the hierarchy of life shows that new kinds of individuals have evolved. A variety of criteria have been used to define biological (...) individuality. Some criteria rely on the presence/absence of a particular property while others advocate an approach that reflects the process of natural selection. The plethora of approaches to classifying individuality has resulted in confusion regarding how to study individuality in a given taxon. (shrink)

Evolutionary theory is formulated in terms of individuals that carry heritable information and are subject to selective pressures. However, individuality itself is a trait that had to evolve - an individual is not an indivisible entity, but a result of evolutionary processes that necessarily begin at the lower level of hierarchical organisation. Traditional approaches to biological individuality focus on cooperation and relatedness within a group, division of labour, policing mechanisms and strong selection at the higher level. Nevertheless, despite (...) considerable theoretical progress in these areas, a full dynamical first-principles account of how new types of individuals arise is missing. To the extent that individuality is an emergent trait, the problem can be approached by recognising the importance of individuating mechanisms that are present from the very beginning of the transition, when only lower-level selection is acting. Here we review some of the most influential theoretical work on the role of individuating mechanisms in these transitions, and demonstrate how a lower-level, bottom-up evolutionary framework can be used to understand biological complexity involved in the origin of cellular life, early eukaryotic evolution, sexual life cycles and multicellular development. Some of these mechanisms inevitably stem from environmental constraints, population structure and ancestral life cycles. Others are unique to specific transitions - features of the natural history and biochemistry that are co-opted into conflict mediation. Identifying mechanisms of individuation that provide a coarse-grained description of the system's evolutionary dynamics is an important step towards understanding how biological complexity and hierarchical organisation evolves. In this way, individuality can be reconceptualised as an approximate model that with varying degrees of precision applies to a wide range of biological systems. (shrink)

The emergence of individuality during the evolutionary transition from single cells to multicellularity poses a range of problems. A key issue is how variation in lower‐level individuals generates a corporate (collective) entity with Darwinian characteristics. Of central importance to this process is the evolution of a means of collective reproduction, however, the evolution of a means of collective reproduction is not a trivial issue, requiring careful consideration of mechanistic details. Calling upon observations from experiments, we draw attention (...) to proto‐life cycles that emerge via unconventional routes and that transition, in single steps, individuality to higher levels. One such life cycle arises from conflicts among levels of selection and invokes cheats as a primitive germ line: it lays the foundation for collective reproduction, the basis of a self‐policing system, the selective environment for the emergence of development, and hints at a plausible origin for a soma/germ line distinction. (shrink)

Sometimes themes can be found in common across very different systems in which change occurs. Imre Lakatos developed a theory of change in science, and one involving entities visible at different levels. There are theories defended at a particular time, and there are also research programs, larger units that bundle together a sequence of related theories and within which many scientists may work. Research programs are competing higher-level units within a scientific field. Scientific change involves change within research programs, and (...) change in the ensemble of research programs present at a time, where some will be growing, some shrinking, some progressing, some degenerating. These are also themes in biological evolution. Recent biology has often found itself dealing with the relation between change at a level of "collectives" – such as organisms like us – and change at a lower level – the level of cells, genes, and other evolving parts. This work is continuous with an older discussion, one that arose when biological evolution was no more than a vague speculation, round the beginning of the 19th century. What is the living individual? What is the basic unit of life or living organization? Questions like this were pursued by Goethe, by Erasmus Darwin, the grandfather of Charles, and many others. Initially it was plants, especially, that were seen to raise these problems, and then newly described marine animals with strange life cycles. The discussion was influenced by the rise of the cell theory in the early 19th century, but some writers looked for individuals well below the level of the cell. (shrink)

What was the original Christianity and what changes came in the process of its evolution in the following centuries? The philosophical and exegetical analysis of the gospels and apostolic epistles, the book of the Acts of the Apostles, to a certain extent, allows us to answer this question. In this case, we are talking about the reflection of the teachings of the founder of this course in Judaism in comparison with the subsequent stages of the evolution of Christianity.

There are indications that simple reaction time might have slowed in Western countries, based on both cohort- and multi-study comparisons. A possible limitation of the latter method in particular is measurement error stemming from methods variance, which results from the fact that instruments and experimental conditions change over time and between studies. We therefore set out to measure the simple auditory reaction time (SRT) of 7,081 individuals (2,997 males and 4,084 females) born in Sweden 1959-1985 (subjects were aged between 27 (...) and 54 years at time of measurement). Depending on cut-offs and adjustment for ageing related slowing on SRT, the data suggest that SRT has increased between 3 and 16 ms in the 27 birth years covered in the present sample. The slowing is unlikely to be explained by attrition, as evaluated by comparing the general intelligence × birth-year interactions and standard deviations for both male participants and dropouts, utilizing military conscript cognitive ability data. The present result is consistent with previous studies employing alternative methods, and may result from several synergistic factors, such as possible recent micro-evolutionary trends favouring lower g in Sweden and the effects of industrially produced neurotoxic substances on peripheral nerve conduction velocity. (shrink)

In his book The Evolution of Individuality, Leo Buss attacks a central dogma of the neo-Darwinian (or synthetic) theory of evolution, the idea that the individual is the sole unit of selection, by arguing that individuals themselves emerged as the result of selective forces that regulated the replication of cell lineages for the benefit of the whole organism. Buss also argues that metazoan developmental patterns and life cycles are the products of selection operating on different units of (...) selection, and that there have been transitions between different units of selection during the history of life. Despite the revolutionary character of this book, The Evolution of Individuality in many ways reflects the adaptationist thinking often associated with the synthetic theory. Buss' framework could be improved by giving further consideration to chance factors in the evolution of development, and examining the details of the evolution of ontogeny in more depth. (shrink)

This dissertation is a heuristic and hermeneutic research paper on the evolution of consciousness and the individuation process. I begin by examining the question of the evolution of consciousness and its significance regarding individuation in the work of four different authors: Jung, Neumann, Sri Aurobindo, and Gebser. I then study the nature of the development of the Western mind since the period of the Greek philosophers up to postmodernism and beyond. Finally, I discuss the meaning of the individuation (...) process. ;All four of the authorities referred to on the evolution of consciousness emphasize the need to integrate life around the Self. From the point of view of this study, each brings forward different factors that help one appreciate how consciousness has evolved and how the individuation process can be fostered. An instructive aspect of Neumann's theory is the underlying error in his thinking involving his depiction of the evolution of consciousness as a direct, linear development from matriarchy to patriarchy. Both Sri Aurobindo and Jung saw it as a spiral-like process. The former also describes several different cultural attitudes, each of which can contribute to the realization of an integral consciousness. According to Gebser, the new integral awareness includes the integration of subjectively experienced time, a life of felt-intensity and the concrete realization of spiritual energy in life. ;Regarding the development of the Western mind, not only has there been a widening separation between the spirit and instincts over time, but the intellect has gradually descended from the realm of ideas to the physical universe. This has led to the modern mind and its offshoot, postmodernism. Jung takes us beyond both tendencies, while reconciling the split in the Western psyche. His psychology involves both following a superior will and the in-depth transformation of the chthonic feminine and realization of the chthonic spirit. I support Jung's view with the one held by Sri Aurobindo and his spiritual collaborator, the Mother, contrasting it with views held by Hillman, Ponce, and Fromm. (shrink)

Capturing a scientific change in thinking about personality and individual differences that has been building over the past 15 years, this volume stands at an important moment in the development of psychology as a discipline. Rather than viewing individual differences as merely the raw material upon which selection operates, the contributing authors provide theories and empirical evidence which suggest that personality and individual differences are central to evolved psychological mechanisms and behavioral functioning. The book draws theoretical inspiration from life history (...) theory, evolutionary genetics, molecular genetics, developmental psychology, personality psychology, and evolutionary psychology, while utilizing the theories of the "best and the brightest" international scientists working on this cutting edge paradigm shift. In the first of three sections, the authors analyze personality and the adaptive landscape; here, the authors offer a novel conceptual framework for examining "personality assessment adaptations." Because individuals in a social environment have momentous consequences for creating and solving adaptive problems, humans have evolved "difference-detecting mechanisms" designed to make crucial social decisions such as mate selection, friend selection, kin investment, coalition formation, and hierarchy negotiation. In the second section, the authors examine developmental and life-history theoretical perspectives to explore the origins and development of personality over the lifespan. The third section focuses on the relatively new field of evolutionary genetics and explores which of the major evolutionary forces--such as balancing selection, mutation, co-evolutionary arms races, and drift--are responsible for the origins of personality and individual differences. Existing as a seminal work in the newly emerging evolutionary psychology field, this book is a "must-read" for anyone invested in the development of psychology as a field. (shrink)

A wide range of ecological and evolutionary models predict variety in phenotype or behavior when a population is at equilibrium. This heterogeneity can be realized in different ways. For example, it can be realized through a complex population of individuals exhibiting different simple behaviors, or through a simple population of individuals exhibiting complex, varying behaviors. In some theoretical frameworks these different realizations are treated as equivalent, but natural selection distinguishes between these two alternatives in subtle ways. By investigating an increasingly (...) complex series of models, from a simple fluctuating selection model up to a finite population hawk/dove game, we explore the selective pressures which discriminate between pure strategists, mixed at the population level, and individual mixed strategists. Our analysis reveals some important limitations to the “ESS” framework often employed to investigate the evolution of complex behavior. (shrink)

A wide range of ecological and evolutionary models predict variety in phenotype or behavior when a population is at equilibrium. This heterogeneity can be realized in different ways. For example, it can be realized through a complex population of individuals exhibiting different simple behaviors, or through a simple population of individuals exhibiting complex, varying behaviors. In some theoretical frameworks these different realizations are treated as equivalent, but natural selection distinguishes between these two alternatives in subtle ways. By investigating an increasingly (...) complex series of models, from a simple fluctuating selection model up to a finite population hawk/dove game, we explore the selective pressures which discriminate between pure strategists, mixed at the population level, and individual mixed strategists. Our analysis reveals some important limitations to the ESS framework often employed to investigate the evolution of complex behavior. (shrink)

Given the evolution of the public health (PH) and the changes from the phenomenon of globalization, this area has encountered new ethical challenges. In order to find a coherent approach to address ethical issues in PH policy, this study aimed to identify the evolution of public health ethics (PHE) frameworks and the main moral values and norms in PH practice and policy. According to the research questions, a systematic search of the literature, in English, with no time limit (...) was performed using the main keywords in databases Web of Science (ISI) and PubMed. Finally, the full text of 56 papers was analyzed. Most of the frameworks have common underpinning assumptions and beliefs, and the need to balance PH moral obligation to prevent harm and health promotion with respect for individual autonomy has been specified. As such, a clear shift from liberal values in biomedical ethics is seen toward the community’s collective values in PHE. The main moral norms in PH practice and policy included protecting the population against harm and improving PH benefits, utility and evidenced-based effectiveness, distributive justice and fairness, respect for all, privacy and confidentiality, solidarity, social responsibility, community empowerment and participation, transparency, accountability and trust. Systematic review of PHE frameworks indicates utilization of the aforementioned moral norms through an practical framework as an ethical guide for action in the PH policy. The validity of this process requires a systematic approach including procedural conditions. (shrink)

The evolution of complex life forms, such as multicellular organisms, is the result of a number of evolutionary transitions in individuality (ETIs). Several attempts have been made to explain their origins, many of which have been internalist (i.e., based largely on internal properties of these life form's ancestors). Here, we show how an externalist perspective, via the ecological scaffolding model in which properties of complex life forms arise from an external scaffold, can shed new light on the question (...) of ETIs. Ultimately, we anticipate progress in the field will occur by recognizing the importance of both the internalist and externalist modes of explanation for ETIs. We illustrate this by considering an extension of the ecological scaffolding model by niche construction in which particles modify the environment which later becomes the scaffold giving rise to collective-level individuality. (shrink)

For decades Darwinian processes were framed in the form of the Lewontin conditions: reproduction, variation and differential reproductive success were taken to be sufficient and necessary. Since Buss and the work of Maynard Smith and Szathmary biologists were eager to explain the major transitions from individuals to groups forming new individuals subject to Darwinian mechanisms themselves. Explanations that seek to explain the emergence of a new level of selection, however, cannot employ properties that would already have to exist on that (...) level for selection to take place. Recently, Hammerschmidt et al. provided a ‘bottom-up’ experiment corroborating much of the theoretical work Paul Rainey has done since 2003 on how cheats can play an important role in the emergence of new Darwinian individuals on a multicellular level. The aims of this paper are twofold. First, I argue for a conceptual shift in perspective from seeing cheats as a ‘problem’ that needs to be solved for multi-cellularity to evolve to the very ‘key’ for the evolution of multicellularity. Secondly, I illustrate the consequences of this shift for both theoretical and experimental work, arguing for a more prominent role of ecology and the multi-level selection framework within the debate then they currently occupy. (shrink)

A simple model, illustrating the transition from a population of free swimming, solitary cells to one consisting of small colonies serves as a basis to discuss the evolution of the cooperative group. The transition is the result of a mutation of the dynamics of cell division, delayed cell separation leads to colonies of four cells. With this mutation cooperative features appear, such as synchronised cell divisions within colonies and coordinated flagellar function which enables the colony to swim in definite (...) directions. The selective advantages under given, environmental conditions are defined and the periods necessary for complete allelic replacement in small populations are calculated for asexual and sexual reproduction. The assumption of a steady-state population during allelic substitution is critically considered, particularly under conditions of competition. It is shown that density-dependent population control must operate in the process of selection. Sexual reproduction slows down the rate of selection even though all cells dre haploid. This phenomenon can be explained in general terms of `organizational dominance', where individual units coordinate the function of their neighbours which may be of a different allelotype.Cooperativity is pointed out as an a priori systemic feature which resides in the sub-units of systems, group formation and coordination appears thus as an almost inevitable event. A particular type of system described as ‘closed cycle of positive fitness interaction’ is discussed in more detail. It has the remarkable feature that its members cannot compete with each other; selection takes place between whole cycles .Gonium has a wide spectrum of `somatic plasticity' which enables it to assume various colonial configurations depending on physiological and environmental conditions. This feature can be explained as the result of dynamic flexibilities on the macro-molecular level. The particular relationship between the vast, molecular complexity and the relative simple dynamics of the cell cycle must lead eventually to the genetic fixation of an environmentally induced phenotype. (shrink)

The theory is presented that the sexual process is a repair mechanism which maintains redundancy within the sub-structure of hierarchical, self-reproducing organisms. In order to keep the problems within mathematically tractable limits , a simple model is introduced: a wheel with 6 spokes, 3 of them vital and 3 redundant, symbolizes the individual . Random accidents destroy spokes; the wheels replicate at regular cycles and engage periodically in pairing and repair phases during which missing spokes are copy-reproduced along the intact (...) spokes of the partner wheel.The hierarchical structure of such a system is analysed and an ‘autonomous unit’ is defined: this is the unit of minimal hierarchical complexity which is capable of perpetuating autonomously all higher and all lower levels of the hierarchy; this is the central unit of selection.Four basic, physical parameters are isolated which determine the essential features of any eucaryotic life cycle: 1. The number of levels of the hierarchy ; 2. the relation between the phases of replication and repair ; 3. the duration of potential repair ; 4. the position of the sexual partners within the hierarchy .The evaluation of fitness components is considered in relation to trends of reproductive patterns in evolution. (shrink)

natural selection may show why all (most, some) humans have an opposable thumb, but cannot show why any particular human has one, Karen Neander ([1995a], [1995b]) argues that this is false because natural selection is 'cumulative'. It is argued here, on grounds independent of its cumulativity, that selection can explain the characteristics of individual organisms subsequent to the event. The difference of opinion between Sober and his critics turns on an ontological dispute about how organisms are identified and individuated. The (...) assumption that Sober needs to make his point is extraneous to population genetics, and, for this reason, gratuitous. (shrink)

The amount of information conveyed by linguistic conventions depends on their precision, yet the codes that humans and other animals use to communicate are quite ambiguous: they may map several vague meanings to the same symbol. How does semantic precision evolve, and what are the constraints that limit it? We address this question using a multiplayer gaming app, where individuals communicate with one another in a scaled-up referential game. Here, the goal is for a sender to use black and white (...) symbols to communicate colors. We expected that the players’ mappings between symbols and colors would grow more specific over time, through a selection process whereby precise mappings are preferentially copied. We found that players become increasingly more precise in their use of symbols over the course of their interactions. This trend did not, however, result from selective copying of precise mappings. We explore the implications of this result for the study of lexical ambiguity, Zipf's Law of Meaning, and disagreements over semantic conventions. (shrink)

Scott Soames argues that interpreted in the light of Quine's holistic verificationism, Quine's thesis of underdetermination leads to a contradiction. It is contended here that if we pay proper attention to the evolution of Quine's thinking on the subject, particularly his criterion of theory individuation, Quine's thesis of underdetermination escapes Soames' charge of paradoxicality.

Debates about the theological implications of recent research in the cognitive and evolutionary study of religion have tended to focus on the question of theism. The question of whether there is any disagreement about the conceptualization of the individual human being has been largely overlooked. In this article, I argue that evolutionary and cognitive accounts of religion typically depend upon a view of cognition that conceptually isolates the mind from its particular social and physical environmental contexts. By embracing this view (...) of the mind, these accounts also unwittingly embrace an abstract individualist view of individual personhood that Christian theologians have explicitly battled against. Taken as a whole, the field leaves sufficient room for supplementary theories that are compatible with theological accounts of the relational individual, but in practice, no effort has been made to engage, or even to accommodate, any other view of individual personhood. (shrink)

E.O. Wilson (1975) described humans as one of the four pinnacles of social evolution. The other pinnacles are the colonial invertebrates, the social insects, and the non-human mammals. Wilson separated human sociality from that of the rest of the mammals because, with the exception of the social insect like Naked Mole Rats, only humans have generated societies of a grade of complexity that approaches that of the social insects and colonial invertebrates. In the last few millennia, human societies have (...) even begun to exceed, in numbers of individuals and degree of complexity, the societies of ants, termites, and corals. (shrink)

The evolution of color categorization systems is investigated by simulating categorization games played by a population of artificial agents. The constraints placed on individual agent’s perception and cognition are minimal and involve limited color discriminability and learning through reinforcement. The main dynamic mechanism for population evolution is pragmatic in nature: There is a pragmatic need for communication between agents, and if the results of such communications have positive consequences in their shared world then the agents involved are positively (...) rewarded, whereas if the results have negative consequences, then involved agents are punished. A mechanism for changing the composition of the population due to agents’ birth and death is also investigated. This birth-death mechanism is found to effectively move an established population color naming system toward a theoretically more optimal one. The simulation results of this article provide insights regarding mechanisms that may constrain universal tendencies in human color categorization systems observed in the linguistic and anthropological literatures. (shrink)

E.O. Wilson (1975) described humans as one of the four pinnacles of social evolution. The other pinnacles are the colonial invertebrates, the social insects, and the non-human mammals. Wilson separated human sociality from that of the rest of the mammals because, with the exception of the social insect like Naked Mole Rats, only humans have generated societies of a grade of complexity that approaches that of the social insects and colonial invertebrates. In the last few millennia, human societies have (...) even begun to exceed, in numbers of individuals and degree of complexity, the societies of ants, termites, and corals. (shrink)

Using evolutionary game theory, I consider how guilt can provide individual fitness benefits to actors both before and after bad behavior. This supplements recent work by philosophers on the evolution of guilt with a more complete picture of the relevant selection pressures.

If all origins of life or of any new grade, level, or major transition as such begin with “competitive development”—with juveniles rather than adults, and multiple individuals rather than a single one—then the evolution of progeneration and of replication always requires an explanation. This article proposes that principles of evolutionary ecology such as density-dependence can be used to explain three kinds of developmental repetitions, viz., sequences of inductive and niche-constructing interactions between the ecological environment and population members, which take (...) place in such a way that the sequence is repeated: individual or somatic repetitions, discussed in Section 1, demographic or progenerative repetitions , discussed in Section 2, and replicative repetitions , discussed in Section 3. This results in a statement of the evolutionary process that includes rather than excludes development and ecology, but one which requires some additions to Van Valen’s aphorism that evolution is the control of development by ecology. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:The Evolution of the Society for the Advancement of American PhilosophyJames Campbelldespite my increasingly decrepit appearance, I can lay no claim to being one of the founders of SAAP. When I joined the Society in the mid-1970s, it was already a well-functioning organization—if a much smaller one than today. After a few years of attending meetings, I began to submit papers, and I first appeared on the program (...) at our sixth annual meeting at John Carroll University in 1979. (See Fig. 1, the complete program, below.) While I was not one of the founders of SAAP, I did know them all. Presiding at the early meetings were, in the order of their presidencies, such elders as John Lachs, John J. McDermott, Darnell Rucker, James Gouinlock, Beth J. Singer, Peter H. Hare, Sandra B. Rosenthal, Thelma Z. Lavine, Joseph Betz, Charlene Haddock Seigfried, and Andrew J. Reck. Serving in the background at the same time were such patron saints as Justus Buchler, Douglas Greenlee, Abraham Edel, Max Harold Fisch, Elizabeth Flower, Edward H. Madden, David L. Miller, Frank M. Oppenheim, Evelyn Shirk, John E. Smith, and H. S. Thayer. It was a good time to be coming to American Philosophy, under the guidance of a Society that respected the fundamentals of pluralism and "fallibilism."1IThe brief discussion of the evolution of SAAP that I offer here initially emphasizes what the Society has meant to me over nearly five decades.2 As I was entering graduate school in 1974, I was drawn by the American philosophical tradition. It was, as William James writes, my "dumb conviction" that the best answers were to be found in this philosophical direction and not in the others, and that my job was to pursue these answers.3 What I found in this tradition was a refuge from both the analytic style of philosophy then dominant in America, with what I saw as its obsession with truth4 and its [End Page 1] confusion of cleverness with wisdom, and the alternatives of the various continental traditions that, although they pursued wisdom, seemed to me to rely too strongly on the mysterious or the untranslatable. My own sense of the American philosophical tradition at the time was an amalgam of Puritanism, Deism, Transcendentalism, Pragmatism in its various forms, and a large dose of Columbia Naturalism. Through further study and especially through my interactions at SAAP meetings, I became more grounded in these approaches and more open to other strands within the tradition.5 For me, cooperative interaction with others was essential to further understanding. Just as for Josiah Royce, the secret was "the community."6Among the lessons that I drew from the American philosophical tradition were the following. I knew that it was necessary to resist the human tendency to believe that what works for me will work for everyone else. As George Santayana reminds us, all philosophy is "personal."7 Thus, certain thinkers and certain thoughts will benefit from their initial plausibility to us, and other thoughts and thinkers will be initially suspect. To counter this personal prejudice, we need to partake in careful, long-term study. On a related point, Ralph Waldo Emerson urges us to seek insight from others, to accept what he calls "provocation" while not accepting their answers.8 At the same time, we live among these other individuals, marry them, teach their children, and benefit from their contributions to our social existence. In other words, American Philosophy teaches us that people are social creatures—a point which both Emerson and James were wary of, but not blind to—and that our thinking should focus on the world of shared experience. As Benjamin Franklin writes, our efforts in "Philosophy" make sense only when our pursuit of wisdom is related to human well-being.9 This point is so important that we need to wonder how our efforts were ever allowed to narrow and separate from a broad sense of human welfare to focus upon supposedly more important minutiae. With John Dewey, I saw the job of philosophers to be helping individuals to understand and deal with their philosophical "problems" of living.10 And, perhaps more... (shrink)

Aspects of human symbolic evolution are studied by scholars active in a variety of fields and disciplines in the life and the behavioral sciences as well as the scientific-philosophical, sociological, anthropological, and linguistic sciences. These fields and disciplines all take on an evolutionary approach to the study of human symbolism, but scholars disagree in their theoretical and methodological attitudes. Theoretically, symbolism is defined differentially as knowledge, behavior, cognition, culture, language, or social group living. Methodologically, the diverse symbolic evolution (...) sciences establish their teachings upon diverging evolutionary biological schools and paradigms. This chapter reviews past and current research fields in human symbolic evolution for how they differentially implement tenets of the major evolution schools that were discussed in the previous chapter. Traditional evolutionary epistemology and biosemiotics bring in a mesoevolutionary outlook by drawing on early Darwinism and evolutionary developmental biology movements that emphasize the role of the organism in evolution. Communication studies instead originally take on a microevolutionary perspective by investigating how units of information are transmitted across generations through time. Only later do they integrate studies on meaning-making at the organismal level. Sociobiology complements a microevolutionary with a macroevolutionary outlook by implementing population genetic approaches, typical of the Modern Synthesis, into studies on individual and group behavior. The new symbolic evolutionary sciences build upon these traditions and include disciplines such as evolutionary psychology, evolutionary linguistics, evolutionary anthropology, evolutionary archaeology, evolutionary sociology, and evolutionary economics. Originally centered on implementing Darwinian selection theory, these fields are now including ecological and evolutionary developmental biology as well as reticulate evolutionary paradigms. As diverse in outlook and scope as they are, no discipline holds a privileged position over the other and all have made valuable contributions to our understanding of human symbolic evolution. (shrink)

One of the major developments in cancer research in recent years has been the construction of models that treat cancer as a cellular population subject to natural selection. We expand on this idea, drawing upon multilevel selection theory. Cancer is best understood in our view from a multilevel perspective, as both a by-product of selection at other levels of organization, and as subject to selection at several levels of organization. Cancer is a by-product in two senses. First, cancer cells co-opt (...) signaling pathways that are otherwise adaptive at the organismic level. Second, cancer is also a by-product of features distinctive to the metazoan lineage: cellular plasticity and modularity. Applying the multilevel perspective in this way permits one to explain transitions in complexity and individuality in cancer progression. Our argument is a reply to Germain’s scepticism towards the explanatory relevance of natural selection for cancer. The extent to which cancer fulfills the conditions for being a paradigmatic Darwinian population depends on the scale of analysis, and the details of the purported selective scenario. Taking a multilevel perspective clarifies some of the complexities surrounding how to best understand the relevance of evolutionary thinking in cancer progression. (shrink)

Influential thinkers such as Young, Sugden, Binmore, and Skyrms have developed game-theoretic accounts of the emergence, persistence and evolution of social contracts. Social contracts are sets of commonly understood rules that govern cooperative social interaction within societies. These naturalistic accounts provide us with valuable and important insights into the foundations of human societies. However, current naturalistic theories focus mainly on how social contracts solve coordination problems in which the interests of the individual participants are aligned, not competition problems in (...) which individual interests compete with group interests. In response, I set out to build on those theories and provide a comprehensive naturalistic account of the emergence, persistence and evolution of social contracts. My central claim is that social contracts have culturally evolved to solve cooperation problems, which include both coordination and competition problems. I argue that solutions to coordination problems emerge from “within-group” dynamics, while solutions to competition problems result largely from “between-group” dynamics. (shrink)

The evolution from pre-human primates to modern Homo sapiens is a complex one involving many domains, ranging from the material to the social to the cognitive, both at the individual and the community levels. This article focuses on a critical qualitative transition that took place during this evolution involving both the social and the cognitive domains. For the social domain, the transition is from the face-to-face forms of social interaction and organization that characterize the non-human primates that reached, (...) with Pan, a hiatus due to the centripetal effects that highly individualized behavior has on a social system. The transition is to the relation-based forms of social organization that evolved in the hominins ancestral to Homo sapiens and are universal in human societies today. For the cognitive domain, this transition involves going from behavior responding mainly to phenomenal level sensory inputs to behavior formed in accordance with the concept of a relation, initially abstracted from behavior patterns, then extending the concept of a relation beyond abstraction from behavior patterns to the concept of a relation generated recursively through constructing the relation of a relation. This extension made possible the construction of systems of relations; initially genealogical systems of relations constructed culturally using the logic of recursion, and subsequently, the symbolic, computational systems of kin term relations referred to by anthropologists as kinship terminologies. The latter are “constructed realities” in the sense this term is used by cultural anthropologists. It follows that the evolution of relation-based systems of social interaction is not adequately accounted for through population model evolutionary accounts such as the Dual Inheritance Theory of human evolution since “constructed realities” constitute collectively and publicly shared cultural knowledge rather than the individually and privately possessed knowledge that is assumed in the population model framework for human evolution. (shrink)

We extend previous work by modeling evolution of communication using a spatialized genetic algorithm which recombines strategies purely locally. Here cellular automata are used as a spatialized environment in which individuals gain points by capturing drifting food items and are 'harmed' if they fail to hide from migrating predators. Our individuals are capable of making one of two arbitrary sounds, heard only locally by their immediate neighbors. They can respond to sounds from their neighbors by opening their mouths or (...) by hiding. By opening their mouths in the presence of food they maximize gains; by hiding when a predator is present they minimize losses. We consider the result a 'natural' template for benefits from communication; unlike a range of other studies, it is here only the recipient of communicated information that immediately benefits. (shrink)

By conceptualizing Sexual Selection, Darwin showed a way to analyze intra-specific individual differences within an evolutionary perspective. Interestingly, Sexual Selection is often used to investigate the origins of sports, arts, humor, religion and other phenomena that, in several languages, are simply called “play.” Despite their manifested differences, these phenomena rely on shared psychological processes, including playfulness. Further, in such behaviors there is usually considerable individual variability, including sex differences, and positive relationship with mating success. However, Sexual Selection is rarely applied (...) in the study of play, with exception to what is concerned as infant training behavior for adult sex roles. We offer an integrated grounding of playful phenomena aligning evolutionary propositions based on sexual selection, which might stimulate further exploration of playfulness within evolutionary perspective. (shrink)

Human societies are based on cooperation among large numbers of genetically unrelated individuals. This behavior is puzzling from an evolutionary perspective. Because cooperators are..

Why do societies collapse? We use an individual-based evolutionary model to show that, in environmental conditions dominated by low-frequency variation (“red noise”), extirpation may be an outcome of the evolution of cultural capacity. Previous analytical models predicted an equilibrium between individual learners and social learners, or a contingent strategy in which individuals learn socially or individually depending on the circumstances. However, in red noise environments, whose main signature is that variation is concentrated in relatively large, relatively rare excursions, individual (...) learning may be selected from the population. If the social learning system comes to lack sufficient individual learning or cognitively costly adaptive biases, behavior ceases tracking environmental variation. Then, when the environment does change, fitness declines and the population may collapse or even be extirpated. The modeled scenario broadly fits some human population collapses and might also explain nonhuman extirpations. Varying model parameters showed that the fixation of social learning is less likely when individual learning is less costly, when the environment is less red or more variable, with larger population sizes, and when learning is not conformist or is from parents rather than from the general population. Once social learning is fixed, extirpation is likely except when social learning is biased towards successful models. Thus, the risk of population collapse may be reduced by promoting individual learning and innovation over cultural conformity, or by preferential selection of relatively fit individuals as models for social learning. © 2009 Elsevier Inc. All rights reserved. (shrink)

The centrality of glory, contempt, and revengefulness to Leviathan’s account of war is highlighted by three contextual features: Hobbes’s displacement of the traditional conception of glory as intrinsically intersubjective and comparative; his incorporation of the Aristotelian view that revengefulness is provoked by expressions of mere contempt; and the evolution of his account between 1640 and 1651. An archeology of Leviathan’s famous chapter thirteen confirms that Hobbes’s thesis throughout his career was that disagreement is the universal cause of war because (...) prickly, glory-seeking humans view its expression as a sign of contempt: although Leviathan abandons Hobbes’s previous argument that war is primarily rooted in vainglorious individuals pursuing domination, Leviathan’s ‘glory’ argument for war is a descendent of the older ‘comparison’, not ‘vanity’, argument. (shrink)

The dynamics of populations of self-replicating, hierarchically structured individuals, exposedto accidents which destroy their sub-units, is analyzed mathematically, specifically with regardto the roles of redundancy and sexual repair. The following points emerge from this analysis:0 A population of individuals with redundant sub-structure has no intrinsic steady-statepoint; it tends to either zero or infinity depending on a critical accident rate α c . Increased redundancy renders populations less accident prone initially, but populationdecline is steeper if a is greater than a fixed (...) value α d . Periodic, sexual repair at system-specific intervals prevents continuous decline and stabilizesthe population insofar as it will now oscillate between two fixed population levels. The stabilizing sexual interval increases with increased complexity provided this is accom-panied by appropriate levels of redundancy. The model closely simulates the dynamics of heterosis effects. Repair fitness is a population fitness: the chance of an individual being repaired is a functionof the statistical make-up of the population as a whole at that particular period. Populationsliving at α > α c either engage in sexual repair at the appropriate time or they die out. The mathematical properties of the model illustrate mechanisms which possibly played arole in the evolution of a mortal soma in relation to sexual reproduction. (shrink)

A sweeping new account of the role of power in the evolution of all life on Earth. Power has many dimensions, from individual attributes such as strength and speed to the collective advantages of groups. The Evolution of Power takes readers on a breathtaking journey across history and the natural world, revealing how the concept of power unifies a vast range of phenomena in the evolution of life - and how natural selection has placed humanity and the (...) planet itself on a trajectory of ever-increasing power. Drawing on evidence from fossils, living organisms, and contemporary society, Geerat Vermeij documents increases in power at all scales, from body size, locomotor performance, and the use of force in competition to efficiency in production and consumption within ecosystems. He shows how power - which he defines as the rate at which organisms acquire and apply energy - is tied to the emergence of cooperation, and how the modern economy, which for the first time has established a monopoly over the biosphere by a single species, is a continuation of evolutionary trends stretching back to the dawn of life. Vermeij persuasively argues that we can find solutions to the many problems arising from this extreme concentration of power by broadening our exclusively human-centered perspective. A masterful work by one of today's most innovative and forward-thinking naturalists, The Evolution of Power offers a new understanding of our place in the grand sweep of evolutionary history. (shrink)

Numerous studies show that humans tend to be more cooperative than expected given the assumption that they are rational maximizers of personal gain. As a result, theoreticians have proposed elaborated formal representations of human decision-making, in which utility functions including “altruistic” or “moral” preferences replace the purely self-oriented "Homo economicus" function. Here we review mathematical approaches that provide insights into the mathematical stability of alternative ways of representing human decision-making in social contexts. Candidate utility functions may be evaluated with help (...) of game theory, classical modeling of social evolution that focuses on behavioral strategies, and modeling of social evolution that focuses directly on utility functions. We present the advantages of the latter form of investigation and discuss one surprisingly precise result: “Homo economicus” as well as “altruistic” utility functions are less stable than a function containing a preference for the golden rule or for the common welfare that is only expressed in social contexts composed of individuals with similar preferences. We discuss the contribution of mathematical models to our understanding of human other-oriented behavior, with a focus on the classical debate over psychological altruism. We conclude that human can be psychologically altruistic, but that psychological altruism evolved because it was generally expressed towards individuals that contributed to the actor’s fitness, such as own children, romantic partners and long term reciprocators. (shrink)

This book explains the different approaches to interpreting the Fourth Amendment that the Supreme Court has used throughout American history, concentrating on the changes in interpretation since the Court applied the exclusionary rule to the states in 1961. It examines the evolution of the warrant rule and the exceptions to it, the reasonableness approach, the special needs approach, individual and society expectations of privacy, and the role of the exclusionary rule.

This book explains the different approaches to interpreting the Fourth Amendment that the Supreme Court has used throughout American history, concentrating on the changes in interpretation since the Court applied the exclusionary rule to the states in 1961. It examines the evolution of the warrant rule and the exceptions to it, the reasonableness approach, the special needs approach, individual and society expectations of privacy, and the role of the exclusionary rule.

Human languages, such as French, Cantonese or American Sign Language, are socio- cultural entities. Knowledge of them (`competence') is acquired by exposure to the ap- propriate environment. Languages are maintained and transmitted by acts of speaking and writing; and this is also the means by which languages evolve. The utterances of one generation are processed by their children to form mental grammars, which in some sense summarize, or generalize over, the children's linguistic experiences. These grammars are the basis for the (...) production of a new avalanche of utterances to which the next generation in its turn is subjected. (This picture is simplified, of course, as generations overlap.) Languages inhabit two distinct and separate modes of existence, which have been called (by Chomsky, 1986) `E-Language' and `I-Language'. E-language is the external observable behaviour --- utterances and inscriptions and manifestations of their meanings. E-language is regarded by some as so chaotic and subject to the vicissitudes of everyday human life as to be a poor candidate for systematic study. (E-Language corresponds to what Chomsky, in earlier terminology, called `performance'.) Out of this blooming buzzing confusion the individual child distils an order internal to the mind; the child constructs a coherent systematic set of rules mapping meanings onto forms. This set of rules is the child's I-Language (where `I' is for `internal'). No two individuals' I-Languages have to be the same, although those of people living in the same community will overlap very significantly. But there will usually be at least some slight difference between the I-language features prevalent in one generation and those prevalent in the next. This is the stuff of language evolution, in the sense of the historical development of individual languages, such as Swedish, Navaho or Zulu. (shrink)

Mitochondria exist in large numbers per cell. Therefore, the strength of natural selection on individual mtDNAs for their contribution to cellular fitness is weak whereas the strength of selection in favor of mtDNAs that increase their own replication without regard for cellular functions is strong. This problem has been solved for most mitochondrial genes by their transfer to the nucleus but a few critical genes remain encoded by mtDNA. Organisms manage the evolution of mtDNA to prevent mutational decay of (...) essential services mitochondria provide to their hosts. Bottlenecks of mitochondrial numbers in female germlines increase the homogeneity of mtDNAs within cells and allow intraorganismal selection to eliminate cells with low quality mitochondria. Mechanisms of intracellular “quality control” allow direct selection on the competence of individual mtDNAs. These processes maintain the integrity of mtDNAs within the germline but are inadequate to indefinitely maintain mitochondrial function in somatic cells. (shrink)

Complexity is pleased to announce the installment of Prof Hiroki Sayama as its new Chief Editor. In this Editorial, Prof Sayama describes his feelings about his recent appointment, discusses some of the journal’s journey and relevance to current issues, and shares his vision and aspirations for its future.

Evolutionary explanations of altruism and human cooperation, first set forth by pioneers such as Darwin, Hamilton and Trivers, suggest that biology might be capable of offering a plausible scientific explanation of the core of human morality. According to this project, morality and human cooperation arise when resourcesare scarce; they cannot be exploited by isolated individuals; and individuals cannot maintain a long-term position of domination over others in order to advance their selfish ends. An important philosophical question that arises with respect (...) to this project has to do with the concepts of de morality and moral motivation that itpresupposes. The evolutionary project has not been clear in this respect. The article argues in favor of two theses: 1) evolutionary explanations of cooperation suggest a contractual type of morality, but they are ambiguous regarding the motivations favored by natural selection, thus reflecting, without resolving it, a traditionaldisagreement between Hobbes’s moral contractualism (selfish motivations) and that of Kant (altruistic motivations); 2) in their current form, these explanations cannot resolve that disagreement, but a reflection on the role of the capacity to interpret the motivations and character of others in the evolution of morality could provide arguments in favor of Kantian contractualism. (shrink)

Even for those who do not believe in a life after death, the idea of the afterlife that a past culture held can serve as a marker in the evolution of human consciousness. Like a demarcation that begins a process of map-making, the description of the time and space of the life after death starts a process of exploring the nature of consciousness and the cultural ideas of individuation that derive from it. World literature is the chronicle of this (...) cultural process of individuation, and literary works of the past serve as milestones on the historical path of the moral and psychological development of humanity. (shrink)