Dominance and prestige as differential predictors of aggression and testosterone levels in men

The relationship between self-esteem and aggression has yielded mixed results and generated much recent debate in the social psychology literature. Based on an evolutionary-psychological theory of self-esteem, Kirkpatrick et al. [Kirkpatrick, L. A., Waugh, C. E., Valencia, A., Webster, G., 2002. The functional domain-specificity of self-esteem and the differential prediction of aggression. Journal of Personality and Social Psychology 825, 756–767] showed that multiple, functionally distinct self-esteem mechanisms predict aggression differentially: e.g., “self-perceived superiority” is positively related, and “social inclusion” inversely related, to behavioral aggression. The present study extends this research by further differentiating two distinct forms of “superiority,” dominance and prestige [Henrich, J., Gil-White, F. J. 2001. The evolution of prestige: Freely conferred deference as a mechanism for enhancing the benefits of cultural transmission. Evolution and Human Behavior 22, 165–196], in the prediction of aggression in men and women and testosterone levels (measured in saliva samples) in men. Dominance was positively related, but prestige was either unrelated or inversely related, to self-report aggression measures. Dominance was unrelated but prestige inversely related to testosterone levels in men, perhaps suggesting a method of testosterone inhibition in individuals attaining prestige-based superiority. In addition to contributing to the growing literature on the aggression–self-esteem link, the results provide validation for the prestige–dominance distinction and support, but also suggest an important refinement to, a theory of self-esteem as a collection of functionally distinct adaptations.     

The evolution of creationists in the United States: Where are they now,and where are they going?

The history of anti-evolutionism in the United States begins only in the early decades of the 20th century but has evolved considerably since then. Various versions of the movement (“equal time” for creationism, “creation science”, “intelligent design”) have developed over time, but they have made few positive contributions to serious discourse about science and religion. Their main goal has been to try to stop the teaching of evolution. The most recent version of creationism, “intelligent design” (ID), has little in common with William Paley's 18th-century version: ID posits an interventionist Deity who regularly interferes in natural processes to produce complex biological structures and functions. The 2005 “intelligent design” trial in Dover, Pennsylvania, destroyed any pretensions that the movement had to scientific integrity. However, anti-evolutionists continue to foment discord at local levels, where opposition to the teaching of evolution can be presented without strong resistance. Scientists can best demonstrate their concern by becoming involved in federal, state, and local administrative processes that determine curricula and develop and adopt textbooks and other instructional materials. To cite this article: K. Padian, C. R. Biologies 332 (2009).     

De-Privatizing Self-Harm: Remembering the Social Self in <Emphasis Type="Italic">How to Forget</Emphasis>

This article reads Malu De Martino’s 2010 film Como Esqueçer (How to Forget) as a case study in self-harm as a mode of expression and self-inquiry. Drawing on disability and queer theory, psychoanalysis, and sociology of medicine, the author argues that How to Forget charts a “crip” epistemology of self-harm and theorizes a “social self.” That is to say, the film models an orientation towards self-harm that offers a coalitional and social therapeutic understanding. Based on this reading, the author suggests the application of practices of knowing-with, or knowing-in-relation as “cripistemology” to a broader therapeutic, research, and lay context.     

Imitation or innovation? Unselective mixed strategies can provide a better solution

Current theory about the evolution of social learning in a changing environment predicts the emergence of mixed strategies that rely on some selective combination of social and asocial learning. However, the results of a recent tournament of social learning strategies [Rendell et al. Science 328(5975):208?C213, 2010] suggest that the success relies almost entirely on copying to learn behavior. Those authors conclude that mixed strategies are vulnerable to invasion by individuals using social learning strategies alone. Here we perform a competition using unselective strategies that differ only in the degree of social versus asocial learning. We show that, under the same conditions of the aforementioned tournament, a pure social learning strategy can be invaded by an unselectively mixed strategy and attain an equilibrium where the latter is majority. Although existing theory suggests that copying other individuals unselectively is not adaptive, we show that, at this equilibrium, the average individual fitness of the population is higher than for a population of pure asocial learners, overcoming Rogers?? paradox in finite populations.     

Evolution of photosynthetic reaction centers

The common ancestor of all photosynthetic prokaryotes and organelles contained chlorophyll (Chl) a. All green and purple photosynthetic bacteria descended from a common bacteriochlorophyll (Bchl) a-containing ancestor which diverged from the Chl a line. Separate PS-I and PS-II reaction centers may have evolved before the appearance of Bchl a. When the transition to Bchl a occurred, the resultant organism contained two types of reaction center, “PS-I” and “PS-II.” One line of development eliminated “PS-II” and evolved into the green bacteria. The other line eliminated “PS-I” and became the purple bacteria. In the Chl a-containing organisms the evolution of PS-II continued until oxygen evolution was achieved.     

The social biology of domiciliary cockroaches: colony structure, kin recognition and collective decisions

A substantial body of research on eusocial insects seen in the last decades has gone hand-in-hand with the development of social evolution theory. In contrast, little attention has been given to the non-eusocial insect species that nevertheless exhibit a rich spectrum of social behaviours, thus effectively skewing our vision of insect sociality. Recent studies on the behaviour, ecology and genetic of “gregarious” cockroaches (Blattodea) have revealed a diversity of social structures and group dynamics unique among insects, providing an important comparative model for the broader understanding of insect social evolution. Here, we present an overview of the social biology of the domiciliary cockroaches (ca. 25 species adapted to human habitats) based on research on two model species, Blattella germanica and Periplaneta americana. We discuss the evolution of these domiciliary cockroaches, considering them in the context of “social herds” within the insect sociality framework.     

How to Rethink Evolutionary Theory: A Plurality of Evolutionary Patterns

Nature has recently depicted the empirical advancements of the theory of evolution as a confrontation between “reformists”, that claim for an urgent rethinking of the standard neo-Darwinian approach including so far neglected factors and processes, and “conservatives” who reply “all is well” about the current evolutionary research programme based on genetic variation and natural selection. The fight is mainly around genetic reductionism, but it seems inconclusive. Reformists stress very important factors, but they are still missing a coherent proposal about the architecture of the future extended evolutionary theory. Conservative react defensively, relying just on non-essential add-ons to the old and stable neo-Darwinian core. We analyze the debate and we propose an interpretation. Evolutionary biology is a rapidly expanding field. The bone of contention is how to update and extend the central core of the Darwinian legacy. We propose here the idea that what is happening in the field today is a development of the evolutionary research programme, whose structure is composed of a set of compatible and integrated evolutionary patterns. Evolutionary biology has been extended over its history by the inclusion of more and more patterns, rather than by revision to core theory. Niles Eldredge’s “Hierarchy Theory” is an example of global structure (meta-theory) aiming at incorporating and unifying the currently observed evolutionary patterns.     

Evolutionary psychology and the generation of culture,part II: Case study: A computational theory of social exchange

Models of the various adaptive specializations that have evolved in the human psyche could become the building blocks of a scientific theory of culture. The first step in creating such models is the derivation of a so-called “computational theory” of the adaptive problem each psychological specialization has evolved to solve. In Part II, as a case study, a sketch of a computational theory of social exchange (cooperation for mutual benefit) is developed. The dynamics of natural selection in Pleistocene ecological conditions define adaptive information processing problems that humans must be able to solve in order to participate in social exchange: individual recognition, memory for one's history of interaction, value communication, value modeling, and a shared grammar of social contracts that specifies representational structure and inferential procedures. The nature of these adaptive information processing problems places constraints on the class of cognitive programs capable of solving them; this allows one to make empirical predictions about how the cognitive processes involved in attention, communication, memory, learning, and reasoning are mobilized in situations of social exchange. Once the cognitive programs specialized for regulating social exchange are mapped, the variation and invariances in social exchange within and between cultures can be meaningfully discussed.     

The Cultural Dynamics of Copycat Suicide

The observation that suicides sometimes cluster in space and/or time has led to suggestions that these clusters are caused by the social learning of suicide-related behaviours, or “copycat suicides”. Point clusters are clusters of suicides localised in both time and space, and have been attributed to direct social learning from nearby individuals. Mass clusters are clusters of suicides localised in time but not space, and have been attributed to the dissemination of information concerning celebrity suicides via the mass media. Here, agent-based simulations, in combination with scan statistic methods for detecting clusters of rare events, were used to clarify the social learning processes underlying point and mass clusters. It was found that social learning between neighbouring agents did generate point clusters as predicted, although this effect was partially mimicked by homophily (individuals preferentially assorting with similar others). The one-to-many transmission dynamics characterised by the mass media were shown to generate mass clusters, but only where social learning was weak, perhaps due to prestige bias (only copying prestigious celebrities) and similarity bias (only copying similar models) acting to reduce the subset of available models. These findings can help to clarify and formalise existing hypotheses and to guide future empirical work relating to real-life copycat suicides.     

Some Possible Cases of Escape Mimicry in Neotropical Butterflies

The possibility that escape or evasive mimicry evolved in butterflies and other prey insects in a similar fashion to classical Batesian and Müllerian mimicry has long been advanced in the literature. However, there is a general disagreement among lepidopterists and evolutionary biologists on whether or not escape mimicry exists, as well as in which mimicry rings this form of mimicry has evolved. Here, we review some purported cases of escape mimicry in Neotropical butterflies and suggest new mimicry rings involving several species of Archaeoprepona, Prepona, and Doxocopa (the “bright blue bands” ring) and species of Colobura and Hypna (the “creamy bands” ring) where the palatability of butterflies, their ability to escape predator attacks, geographic distribution, relative abundance, and co-occurrence in the same habitats strongly suggest that escape mimicry is involved. In addition, we also indicate other butterfly taxa whose similarities of coloration patterns could be due to escape mimicry and would constitute important case studies for future investigation.     

Natural selection through survival alone,and the possibility of Gaia

Here I advance two related evolutionary propositions. (1) Natural selection is most often considered to require competition between reproducing “individuals”, sometimes quite broadly conceived, as in cases of clonal, species or multispecies-community selection. But differential survival of non-competing and non-reproducing individuals will also result in increasing frequencies of survival-promoting “adaptations” among survivors, and thus is also a kind of natural selection. (2) Darwinists have challenged the view that the Earth’s biosphere is an evolved global homeostatic system. Since there is only one biosphere, reproductive competition cannot have been involved in selection for such survival-promoting adaptations, they claim. But natural selection through survival could reconcile Gaia with evolutionary theory.     

Depth-selection behavior and longevity in Daphnia: an evolutionary test for the predation-avoidance hypothesis

The classic evolutionary theory of senescence predicts that long lifespan evolves under low risk of extrinsic mortality. As lakes present planktonic animals with vertical gradients of mortality risk associated with fish predation, we expected the individual lifespan of Daphnia of the “hypolymnetic” clones to be longer than that of “epilimnetic” Daphnia. In order to test this prediction, we performed a laboratory study on 14 clones from the D. longispina species complex, taken during the daytime either from epilimnion or hypolimnion of three mesotrophic lakes. “Epilimnetic” Daphnia started reproduction earlier, aged faster, and lived shorter than their “hypolimnetic” conspecifics. Our results indirectly support the predation-avoidance hypothesis as the ultimate explanation for depth-selection behavior in Daphnia.     

Structure for energy cycle: a unique status of the second law of thermodynamics for living systems

Distinguishing things from beings, or matters from lives, is a fundamental question. Extending E. Schr?dinger's neg-entropy and I. Prigogine's dissipative structure, we propose a chemical kinetic view that the earliest "live" process is embedded essentially in a special interaction between a pair of specific components under a particular, corresponding environmental conditions. The interaction exists as an inter-molecular-force-bond complex(IMFBC) that couples two separate chemical processes: one is the spontaneous formation of the IMFBC driven by a decrease of Gibbs free energy as a dissipative process; while the other is the disassembly of the IMFBC driven thermodynamically by free energy input from the environment. The two chemical processes coupled by the IMFBC originated independently and were considered non-living on Earth, but the IMFBC coupling of the two can be considered as the earliest form of metabolism: the first landmark on the path from things to a being. The dynamic formation and disassembly of the IMFBC, as a composite individual, follows a principle designated as "… structure for energy for structure for energy…", the cycle continues; and for short it will be referred to as "structure for energy cycle". With additional features derived from this starting point, the IMFBC-centered "live" process spontaneously evolved into more complex living organisms with the characteristics currently known.     

“Realism” and “relevance” in gaming simulations

How useful are gaming simulations for the study of problems that interest human ecologists? Anatol Rapoport, a principal contributor to the development of game theory, raised this issue with the editors of Human Ecology,who in turn invited him to express his views in print. In brief, Dr. Rapoport calls into question the real-world applicability of gaming simulations, and explores its limitations. The educational function of simulation, he argues, should not be confused with the research aims of laboratory experimentation. The addition of “realistic” conditions in a gaming simulation merely complicates the experiment and reduces its theoretical significance. It does, however, have some pedagogical utility, whose implications have not yet been adequately taken into account. Dr. Rapoport considers this matter with reference to the problem of “social traps,” such as the “tragedy of the commons,” an issue which concerns many human-ecology researchers.     

Evolution and plasticity: Divergence of song discrimination is faster in birds with innate song than in song learners in Neotropical passerine birds

Plasticity is often thought to accelerate trait evolution and speciation. For example, plasticity in birdsong may partially explain why clades of song learners are more diverse than related clades with innate song. This “song learning” hypothesis predicts that (1) differences in song traits evolve faster in song learners, and (2) behavioral discrimination against allopatric song (a proxy for premating reproductive isolation) evolves faster in song learners. We tested these predictions by analyzing acoustic traits and conducting playback experiments in allopatric Central American sister pairs of song learning oscines (N = 42) and nonlearning suboscines (N = 27). We found that nonlearners evolved mean acoustic differences slightly faster than did leaners, and that the mean evolutionary rate of song discrimination was 4.3 times faster in nonlearners than in learners. These unexpected results may be a consequence of significantly greater variability in song traits in song learners (by 54–79%) that requires song‐learning oscines to evolve greater absolute differences in song before achieving the same level of behavioral song discrimination as nonlearning suboscines. This points to “a downside of learning” for the evolution of species discrimination, and represents an important example of plasticity reducing the rate of evolution and diversification by increasing variability.     

“Candidatus Defluviella procrastinata” and “Candidatus Cyrtobacter zanobii”, Two Novel Ciliate Endosymbionts Belonging to the “Midichloria Clade”

The “Midichloria clade” is a recently discovered but well-established evolutionary lineage clustering inside the order Rickettsiales (Alphaproteobacteria). Not much is known about the biology of these organisms. The best characterized ones are endocellular symbionts of very different eukaryotic hosts, ranging from arthropods to protists. “Candidatus Midichloria mitochondrii”, the most studied organism of the group, is an interesting object of study because of its unique capability to infect metazoans’ mitochondria and the presence of flagellar genes in its genome. With this work, we aim at increasing the knowledge on the biodiversity and phylogeny of the “Midichloria group”. We characterized according to the “full cycle rRNA approach” two novel endosymbionts of ciliated protozoa, i.e. Paramecium nephridiatum and Euplotes aediculatus. According to the nomenclatural rules for uncultivated prokaryotes, we established the novel taxa “Candidatus Defluviella procrastinata” and “Candidatus Cyrtobacter zanobii” for the two bacterial symbionts. Our phylogenetic analysis based on 16S rRNA gene sequences confirms that the evolutionary histories of “Midichloria clade” representatives and of their hosts are very different. This suggests that the symbiotic processes arose many times independently, perhaps through ways of transmission still not described in Rickettsiales.     

Adaptive glenoid bone remodeling simulation

Glenoid prosthesis loosening is the most common cause for revision total shoulder arthroplasty. Stress-induced bone remodeling may compromise long-term prosthesis fixation and significantly contribute to loosening. Realistic, robust analysis of bone-prosthesis constructs need to look beyond initial post-implantation mechanics provided by static finite element (FE) simulation. Adaptive bone remodeling simulations based on Wolff's law are needed for evaluating long-term glenoid prostheses fixation. The purpose of this study was to take a first step towards this goal and create and validate two-dimensional FE simulations, using the intact glenoid, for computing subject-specific adaptive glenoid remodeling. Two-dimensional glenoid FE models were created from scapulae computed tomography images. Two distinct processes, “element” and “node” simulations, used the forward-Euler method to compute bone remodeling. Initial bone density was homogeneous. Center and offset load combinations were iteratively applied. To validate the simulations we performed location-specific statistical comparisons between predicted and actual bone density, load combinations, and “element” and “node” processes. Visually and quantitatively “element” simulations produced better results (p>0.22), and correlation coefficients ranged 0.51–0.69 (p<0.001). Having met this initial work's goals, we expect subject-specific FE glenoid bone remodeling simulations together with static FE stress analyses to be effective tools for designing and evaluating glenoid prostheses.     

Including exclusion: the enduring problematic gap between the race and ethnicity paradigms

In the article, “U.S. Racial and Ethnic Relations in the Twenty-first Century”, Zulema Valdez and Tanya Golash-Boza present a compelling argument, suggesting the existence of a gap in race theoretical paradigms and ethnicity theoretical paradigms. They suggest that these two theoretical frames focus on both different social processes and levels of analysis, and argue for a merging of the central tenets of these paradigms in order to facilitate more complete theoretical analyses of racial and ethnic processes in the U.S. While we see great value in this project, we suggest that the authors miss an enduring and problematic gap between these theoretical frames because they do not fully explicate how race/racism theory articulates the fundamentally interconnected relationships between the racial social structure, group-level processes, and individual-level racial dynamics in a manner that ethnicity theory fails to capture.