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1.
Evolutionary biology, indeed any science that attempts to reconstruct prehistory, faces practical limitations on available data. These limitations create the problem of contrast failure: specific observations may fail to discriminate between rival evolutionary hypotheses. Assessing the risk of contrast failure provides a way to evaluate testing protocols in evolutionary science. Here I will argue that part of the methodological critique in the Spandrels paper involves diagnosing contrast failure problems. I then distinguish the problem of contrast failure from the more familiar philosophical problem of underdetermination, and demonstrate how contrast failure arises in scientific practice with an investigation into Lewontin and White’s (Evolution 14:116–129, 1960) estimation of an adaptive landscape.
Patrick ForberEmail:
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The effects of physical and mental countermeasures on the accuracy of the concealed information test (CIT) were examined in a mock crime experiment with 64 participants. To combat countermeasures, two covert respiration measures, hidden in the seat and back of the examination chair, were used in addition to the standard physiological measures (SCR, FPWL, RLL). Some guilty participants were trained to use either physical or mental countermeasures and apply them to distort the outcomes of the CIT. In the second phase of the experiment participants were detached from the standard polygraph devices and examined solely with the two covert measures. Results indicated that physical countermeasures lowered SCR accuracy but had a relatively small effect on the other standard measures. On the other hand, SCR was relatively resistant to mental countermeasures. Both covert measures were resistant to physical countermeasures in the polygraph phase. When the standard devices were removed, the covert seat measure was effective in the no countermeasure and in the mental countermeasure conditions but not when physical countermeasures were applied. The back measure was entirely ineffective.
Eitan ElaadEmail:
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Sub-Antarctic Marion Island has had a permanent research station for 50 years and the islands Wandering Albatrosses have been intensively studied for 20 years. The reactions of breeding birds to approaches by a human on foot were recorded. Three response variables were calculated: intensity of vocal reaction (IVR), intensity of non-vocal reaction (INR) and overall response index (ORI). At 5 m from the nest, twice as many birds stood and/or vocalised as at 15 m. Nearest neighbour distance, age and gender did not explain individual variability of responses. Study colony birds had higher IVR scores than non-study colony birds; birds at colonies closest to the station had the highest ORI scores. A better breeding record was associated with lower IVR and ORI scores, but a causative relationship remains to be demonstrated. A minimum viewing distance of 25 m is recommended for breeding Wandering Albatrosses.
Marienne S. de VilliersEmail: Fax: +27-21-6503434
John CooperEmail:
Peter G. RyanEmail:
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This paper is intended to complement our previous works on the necessary existence of error-correcting codes endowing genomes with the ability of being regenerated, not merely copied. It sketchily recalls some fundamental definitions and results of information theory and error-correcting codes; provides an overview of our research; shows that the disjunction of replication and regeneration enlightens the divide between germinal and somatic cells; suggests that some phenomena referred to as epigenetic may possibly find an explanation within the framework of error-correcting codes; points out some difficulties, especially those related to sexual reproduction; criticizes the template-replication paradigm, and prompts geneticists to become familiar with information theory.
Gérard BattailEmail:
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The recent contribution by Jarmila Kukalová-Peck on Hennigian phylogenetics and hexapod limb evolution is critically evaluated.
Michael S. Engel (Corresponding author)Email:
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9.
Jablonka and Lamb's claim that evolutionary biology is undergoing a ‘revolution’ is queried. But the very concept of revolutionary change has uncertain application to a field organized in the manner of contemporary biology. The explanatory primacy of sequence properties is also discussed.
Peter Godfrey-SmithEmail:
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Gridcast is an R&D project investigating grid ideas and technologies in the broadcasting technical infrastructure. In this paper I discuss the business and technical issues in building infrastructures to support broadcasters and outline the structure of the Gridcast grid-based service oriented architecture for broadcasting playout support.
Terry HarmerEmail:
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A key point in the analysis of dynamical models of biological systems is to handle systems of relatively high dimensions. In the present paper we propose a method to hierarchically organize a certain type of piecewise affine (PWA) differential systems. This specific class of systems has been extensively studied for the past few years, as it provides a good framework to model gene regulatory networks. The method, shown on several examples, allows a qualitative analysis of the asymptotic behavior of a PWA system, decomposing it into several smaller subsystems. This technique, based on the well-known strongly connected components decomposition, is not new. However, its adaptation to the non-smooth PWA differential equations turns out to be quite relevant because of the strong discrete structure underlying these equations. Its biological relevance is shown on a 7-dimensional PWA system modeling the gene network responsible for the carbon starvation response in Escherichia coli.
Laurent Tournier (Corresponding author)Email:
Jean-Luc GouzéEmail:
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The branch of evolutionary theory known as signaling theory attempts to explain various forms of communication. Social scientists have explained many traditional rituals as forms of communication that promote cooperative social relationships among participants. Both evolutionists and social scientists have realized the importance of trust for the formation and maintenance of cooperative social relationships. These factors have led to attempts to apply signaling theory to traditional cultural rituals in various ways. This paper uses the traditional ritual of mumming in small Newfoundland fishing villages to evaluate alternative hypotheses about the connection between rituals, communication, trust, and cooperation. Mumming is found to be most consistent with the hypothesis that it is a ritual of trust wherein participants take a specific type of risk: the risk of harm at the hands of other participants. Individuals who take this risk actively signal their trust. Conversely, individuals who restrain themselves from inflicting harm on other participants actively signal their trustworthiness.
Christina Nicole PomianekEmail:
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Although recent scholarship on transnational mothers has rigorously examined the effect of migration on gender constructs and ideologies, it neglects analysis of the lived experience of separated mothers and children. In privileging the exploration of transnational separations through the single analytical lens of gender, such research reduces the embodied distress of mothers and children to mere “gender false consciousness.” This paper calls upon anthropologists to redress this oversight by undertaking a phenomenological analysis of the lived experience of transnational motherhood. Eschewing an analysis of mothers and children as isolated social roles, I show that the suffering of mothers and children is profoundly relational. Through analysis of the narratives of undocumented Salvadoran mothers residing in the U.S., I show how the strain of such mothers’ undocumented status is lived and shouldered within the intersubjective space of the family.
Sarah HortonEmail:
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Previous research has demonstrated that hormones, relationship goals, and social context influence interest in the opposite sex. It has not been previously reported, however, whether having a current sexual partner also influences interest in members of the opposite sex. To test this, we obtained explicit and implicit measures of interest by measuring men’s and women’s subjective ratings and response times while they evaluated photos of opposite-sex faces. Fifty-nine men and 56 women rated 510 photos of opposite-sex faces for realism, masculinity, attractiveness, or affect. We found that these subjective ratings were not influenced by partner status in either men or women. However, women who did not report having a current sexual partner spent more time evaluating the photos than women who did have partners, demonstrating greater interest in the photos. Sexual partner status did not predict men’s response times. These findings may reveal that relationship commitment in women suppresses interest in alternative partners.
Heather RuppEmail:
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I show that gene regulation networks are qualitatively consistent and therefore sufficiently similar to linearly seperable connectionist networks to warrant that the connectionist framework be applied to gene regulation. On this view, natural selection designs gene regulation networks to overcome the difficulty of development. I offer some general lessons about their evolvability that can be learned by examining the generic features of connectionist networks.
Roger SansomEmail:
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Problems with studies, claims, and assumptions that have been made about the causes of fires in Indonesia's tropical moist forests are identified, and the kinds of concepts, methods, prioritizing, and data needed to resolve the problems are discussed. Separate sections are devoted to studying ignitions, studying fire susceptibility and fire behavior, and using the goal of causal explanation to guide interdisciplinary research.
Andrew P. VaydaEmail:
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In this paper, we investigate the large-scale synchrony of EEG oscillatory bursts, during stimulation by a flickering square of light. Whereas most studies focus on averaged raw EEG responses, this study considers oscillatory events within EEG of single trials, which leads to various new insights. We recorded EEG signals before, during and after stimulation by a flickering square of light in medium (16 Hz) and high frequency (32 Hz) ranges. Similar oscillatory bursts, to those observed in spontaneous EEG, can be found in single-trial synchrony of steady state visual evoked potentials (SSVEP). These bursts are extracted from the EEG of single trials using bump modeling. Stochastic event synchrony method is applied to those events, which quantifies synchronies of oscillatory bursts on a large-scale basis. Those oscillatory patterns have a significantly higher degree of co-occurrence during SSVEP, uncorrelated with ongoing signal synchrony. It means that EEG oscillatory patterns are presumably an outcome of brain activity, rather than a mere side effect of ongoing EEG. They undergo a consistent reorganization during visual stimulation, preferentially along the visual pathway, depending on magno or parvo stimulations. Flickering stimuli may induce some cognitive side-effects depending on the stimulation frequency.
Francois B. VialatteEmail:
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Inclusive fitness theory provides a compelling explanation for the evolution of altruism among kin. However, a completely satisfactory account of non-kin altruism is still lacking. The present study compared the level of altruism found among siblings with that found among friends and mates and sought to reconcile the findings with an evolutionary explanation for human altruism. Participants (163 males and 156 females) completed a questionnaire about help given to a sibling, friend, or mate. Overall, participants gave friends and mates as much or more help than they gave siblings. However, as the cost of help increased, siblings received a progressively larger share of the help, whereas friends and mates received a progressively smaller share, despite the fact that participants were closer emotionally to friends and mates than they were to siblings. These findings help to explain the relative standing of friends and mates as recipients of altruistic aid.
Steve Stewart-WilliamsEmail:
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Event-related brain potentials (ERP) are important neural correlates of cognitive processes. In the domain of language processing, the N400 and P600 reflect lexical-semantic integration and syntactic processing problems, respectively. We suggest an interpretation of these markers in terms of dynamical system theory and present two nonlinear dynamical models for syntactic computations where different processing strategies correspond to functionally different regions in the system’s phase space.
Peter beim GrabenEmail:
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