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Outgroups
Terms modified by Outgroups Selected AbstractsA "Total Evidence" Analysis of the Phylogenetic Relationships among the Photosynthetic StramenopilesCLADISTICS, Issue 3 2001Ulf SorhannusArticle first published online: 19 JUL 200 Phylogenetic relationships among the nine major autotrophic stramenopile taxa were inferred in a combined analysis of the rbcL, SSU rDNA, partial LSU rRNA, carotenoid, and ultrastructural data sets. The structure of the shortest combined tree is: (Outgroup, ((((Bacillariophyceae, (Pelagophyceae, Dictyochophyceae)),((Phaeophyceae, Xanthophyceae), Raphidophyceae)), Eustigmatophyceae),(Chrysophyceae, Synurophyceae))). The Synurophyceae/Chrysophyceae is the best supported group followed by the Phaeophyceae/Xanthophyceae and the Pelagophyceae/Dictyochophyceae clades. The monophyletic groups composed of Bacillariophyceae/Pelagophyceae/Dictyochophyceae and Phaeophyceae/Xanthophyceae/Raphidophyceae received the lowest Bremer support values. The optimal combined tree suggests that the diatom frustule is derived from the siliceous "skeleton" in Dictyochophyceae, that the reduced flagellar apparatus arose once in the Bacillariophyceae/Dictyochophyceae/Pelagophyceae clade, and that the specific photoreceptor-eyespot apparatus in Chrysophyceae and the Phaeophyceae/Xantophyceae clade originated independently within the autotrophic stramenopiles. Despite conflicts in tree structure between the most-parsimonious combined phylogeny and the optimal tree(s) of each data partition, it cannot be concluded that extensive incongruence exists between the data sets. [source] Phylogenetic analysis of the pearlfish tribe Carapini (Pisces: Carapidae)ACTA ZOOLOGICA, Issue 4 2000E. Parmentier Abstract Fishes of the tribe Carapini (Encheliophis and Carapus) share a noteworthy peculiarity: they shelter in holothurian echinoderms or bivalve hosts. Some species are considered parasitic, others commensal. This study focuses on the phylogeny of the tribe, using two other Carapidae species as an outgroup (Snyderidia canina and Onuxodon fowleri). Insofar as possible, the selected anatomical and behavioural characters where chosen in an ecomorphological perspective, as features that could be responses to various lifestyle-related constraints. Our character selection also took into account the fact that some features are (presumably) linked. Such features were grouped together as a single trait to avoid their overvaluation. This methodology enabled commensals to be separated from parasites, the former belonging to Carapus and the latter to Encheliophis. Carapus species reflect in their morphology the constraints imposed by a diet of hard, mobile, elusive prey, showing predator-type features: a strong dentition, a wide mouth opening, a robust food intake apparatus. On the other hand, the endoparasitic Encheliophis species show a generally weaker buccal apparatus and narrow mouth opening, in relation to the different constraints of their lifestyle where the diet constraints are less pronounced: they eat body parts of their host. Changes in both generic diagnoses are proposed and three species are transferred from Encheliophis to Carapus. [source] Examining dispositional and situational effects on outgroup attitudes,EUROPEAN JOURNAL OF PERSONALITY, Issue 4 2009Joke Meeus Two research lines have dominated the quest for the antecedents of outgroup attitudes. Whereas the first has viewed outgroup attitudes as a result of individual differences, the second stressed the importance of the intergroup situation. In order to investigate the interplay of individual differences and situational characteristics, key predictors of the individual differences perspective (i.e. right-wing authoritarianism or RWA, and social dominance orientation or SDO) and the intergroup relations perspective (i.e. ingroup identification and ingroup threat) were simultaneously tested. Two studies revealed additive but no interaction effects of RWA and SDO, ingroup identification and threat. Additionally, Study 1 showed that threat effects remain limited to the outgroup that is portrayed as threatening and do not generalize to other outgroups. Copyright © 2009 John Wiley & Sons, Ltd. [source] We're warmer (they're more competent): I-sharing and African-Americans' perceptions of the ingroup and outgroupEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 7 2008Elizabeth C. Pinel Researchers currently know very little about how African-Americans regard themselves and their salient outgroup (i.e., European-Americans). The current study examines how experiences with individual ingroup and outgroup members affect these evaluations on two key dimensions in intergroup research: warmth and competence. In particular, the study asks what effect I-sharing (i.e., sharing a subjective experience) with an African-American or a European-American has on African-Americans' perceptions of the warmth and competence of their ingroup and outgroup. Results revealed an ingroup preference on the dimension of warmth when participants had I-shared with a fellow African-American but not when they had I-shared with a European-American. No such ingroup preference emerged on the dimension of competence. Instead, participants exhibited an outgroup preference on this dimension after I-sharing with a European-American. The discussion entertains possible explanations for these differential effects of I-sharing on judgments of the ingroup and outgroup. Copyright © 2008 John Wiley & Sons, Ltd. [source] How does intergroup contact reduce prejudice?EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 6 2008Meta-analytic tests of three mediators Recent years have witnessed a renewal of interest in intergroup contact theory. A meta-analysis of more than 500 studies established the theory's basic contention that intergroup contact typically reduces prejudices of many types. This paper addresses the issue of process: just how does contact diminish prejudice? We test meta-analytically the three most studied mediators: contact reduces prejudice by (1) enhancing knowledge about the outgroup, (2) reducing anxiety about intergroup contact, and (3) increasing empathy and perspective taking. Our tests reveal mediational effects for all three of these mediators. However, the mediational value of increased knowledge appears less strong than anxiety reduction and empathy. Limitations of the study and implications of the results are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] United we win, divided we fail?EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2008Effects of cognitive merger representations, performance feedback on merging groups Research has shown that cognitive representations of mergers influence intergroup evaluations. This paper extends this research by studying how cognitive representations of mergers (one group, dual identity, and two groups) interact with performance feedback (success and failure) to affect intergroup evaluations. Two competing hypotheses were tested, which made different predictions in case of superordinate group salience combined with subgroup salience after merger failure: The subgroup-salience-hypothesis predicts that subgroup salience during a merger generally results in pre-merger ingroup bias toward the pre-merger outgroup (i.e., two groups and dual identity). The superordinate- salience-hypothesis predicts that subgroup salience only results in pre-merger ingroup bias if superordinate group salience is low (i.e., two groups). Both hypotheses predict low levels of ingroup bias after merger success. Study 1 confirmed the second hypothesis using a 3 (merger representation: one group, dual identity, and two groups),×,2 (merger feedback: failure and success) design with interacting groups. Study 2 replicated the results in an adapted minimal group paradigm. Copyright © 2007 John Wiley & Sons, Ltd. [source] Social creativity strikes back: improving motivated performance of low status group members by valuing ingroup dimensionsEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2007Belle Derks Motivation of stigmatized group members to perform on status-relevant ,outgroup' dimensions can be impaired after ingroup failure. Three experiments examined whether social creativity by valuing ingroup dimensions (dimensions on which an ingroup outperforms an outgroup) can increase motivation and performance on outgroup dimensions. It was hypothesized that under high social identity threat, motivation on the outgroup dimension would benefit from valuing an ingroup dimension. Experiments 1 and 2 show that when social identity threat is increased, low status group members who personally value ingroup dimensions show higher motivation to perform on the outgroup dimension. Experiment 3 shows that the induction of high contextual value of both ingroup and outgroup dimensions improves low status group members' well-being and motivated performance on the outgroup dimension. Copyright © 2006 John Wiley & Sons, Ltd. [source] Choice of comparisons in intergroup settings: the role of temporal information and comparison motivesEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 5 2006Rupert J. Brown Three studies investigated comparison choices in intergroup settings, a neglected but important topic for theories of intergroup relations. Two main questions were addressed: What is role of comparison motives in determining comparison choices in intergroup contexts? How important are temporal comparisons (of the ingroup in the past or future) in intergroup settings? In Study 1 (N,=,115), motives for Assessment or Enhancement were primed in a multi-group performance context. Compared to Controls, Assessment priming encouraged both upward and downward comparisons, while Enhancement encouraged mainly downward comparisons. In general, temporal comparisons were as prevalent as comparisons with other groups. Study 2 (N,=,199) employed a real-world setting in which members of a mid-ranking university indicated their interest in comparing with other higher or lower status universities or with their own university in the past. Temporal comparisons were once more much in evidence, and manipulating enhancement motives again encouraged downward comparisons. In Study 3 (N,=,40), set in the context of inter-nation student comparisons, Improvement motives were primed implicitly. This led to an increase in interest in an outgroup just above the ingroup but to a decrease in interest in future-oriented comparisons. Copyright © 2006 John Wiley & Sons, Ltd. [source] In case of death, cling to the ingroupEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 4 2004Emanuele Castano An experiment investigated whether the enhanced importance of the ingroup as a consequence of the salience of death thoughts is a unconscious defense mechanism. Scottish participants were subliminally primed with either the word death or field. Subsequently, they were asked to classify a series of pictures as either English or Scottish, and to state whether a series of negative traits applied to the English or not. Results showed that participants primed with the word death were more likely to exclude targets that looked more like outgroup than ingroup members, than participants in the field (control) prime condition. The pattern observed on the categorization-latency also supported the claim that death-prime participants are more careful in classifying targets. Finally, death-prime participants also conveyed more negative, stereotypical judgments of the English in a trait attribution task. The implications of the results are discussed in relation to terror management theory and social identification phenomena. Copyright © 2004 John Wiley & Sons, Ltd. [source] Group membership and everyday social comparison experiencesEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2004Heather J. Smith In two everyday experience studies, we examined the degree to which everyday social comparisons are framed by group membership. In the first study, 30 undergraduates attending a public university in the United States completed short questionnaires about their social comparison experiences whenever they were signalled. In the second study, 34 ethnic minority undergraduates from the same university completed similar questionnaires about their social comparison experiences. Across both studies, comparisons in which participants viewed themselves as an ingroup member in comparison to an outgroup comprised less than 10% of the comparison experiences reported by participants. However, minorities in the second study who reported closer identification with their ethnic group reported more comparison experiences in which they mentioned their own or the comparison target's ethnicity. Copyright © 2004 John Wiley & Sons, Ltd. [source] Sources of respect: the effects of being liked by ingroups and outgroupsEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2004Naomi Ellemers We investigated the effects of ingroup and outgroup sources of respect, defined as positive social evaluations of self, on group members' emotional reactions and collective self-esteem. We used both natural group memberships (Studies 1 and 2) and laboratory groups (Study 3). We expected that the positive effects of respect derived from an ingroup would not hold when derived from an outgroup source. In Study 1 (N,=,294) respect was manipulated as deriving either from ingroup or outgroup. Although respect produced a positive emotional reaction irrespective of source, collective self-esteem was only enhanced by an ingroup source. In Study 2 (N,=,248), we investigated the concurrent effects of ingroup respect and outgroup respect. As in Study 1, ingroup and outgroup respect both produced positive emotional reactions, but collective self-esteem was only affected by ingroup respect. Additionally, outgroup respect intensified the shame people experienced due to lack of ingroup respect. In Study 3 (N,=,66), participants were immersed in experimental groups and ingroup and outgroup respect were manipulated orthogonally. Interactive effects of the two sources of respect indicated that high outgroup respect could not compensate for low ingroup respect, and if anything had an adverse effect. Copyright © 2004 John Wiley & Sons, Ltd. [source] The importance of social structure and social interaction in stereotype consensus and content: is the whole greater than the sum of its parts?EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 1 2004Clifford Stott This paper addresses the hypothesis derived from self-categorization theory (SCT) that the relationship between groups and stereotyping will be affected by the social structural conditions within which group interaction occurs. A mixed design experiment (n=56) measured low-status groups' stereotypes and preferences for conflict with a high-status outgroup prior to and after within-group discussion across varying social structural conditions. Over time, participants in [open] conditions consensualized around positive conceptions of the outgroup and endorsed acceptance of their own [low status] position. However, in [closed] conditions participants consensualized around positive conceptions of the ingroup, negative conceptions of the outgroup, and tended towards preferences for collective protest. It is argued that the data support S-CT's contention that stereotyping and group processes are fundamentally interlinked and that neither can be properly understood in isolation from the dynamics of the surrounding intergroup context. Copyright © 2004 John Wiley & Sons, Ltd. [source] Perceived legitimacy of intergroup status differences: its prediction by relative ingroup prototypicalityEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 4 2002Ulrike Weber Research demonstrates that the perceived legitimacy of intergroup status differences has profound effects on intergroup attitudes, emotions and behavior. However, there has only been little intergroup research that predicts the perception of legitimacy. We hypothesize that the perception of legitimate or illegitime status relations depends upon the perceived relative prototypicality of the ingroup for the inclusive category. Since the prototype of the inclusive category provides a normative comparison standard for subgroup evaluation, similarity to this standard (i.e. prototypicality) should be positively evaluated and used to justify high status. A first study in a natural intergroup context (N,=,67) offered correlational data in support of the predicted relationship. The second study (N,=,60), using Germans as ingroup with Poles as outgroup and Europe as inclusive category, demonstrated that the link between prototypicality and legitimacy is contingent upon the valence of the inclusive category. In order to elucidate the causal direction, the third study manipulated relative prototypicality in an artificial intergroup context (N,=,94) and introduced status as a moderator variable. Overall, we found strong support for the hypothesis that legitimacy is related to prototypicality and that this relation is moderated by ingroup status and valence of the inclusive category. Copyright © 2002 John Wiley & Sons, Ltd. [source] Compensatory biases after ingroup threat: ,yeah, but we have a good personality'EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 4 2001Maria Rosaria Cadinu It was hypothesized that participants who strongly identify with the ingroup and receive unfavorable feedback about their group in one domain would compensate on alternative dimensions. A group of emergency medical service volunteers received negative, positive or no feedback on their volunteer organization and were asked to rate the ingroup and an outgroup on dimensions alternative to the feedback. As predicted, high identifiers showed an increase in ingroup favoritism after negative feedback (i.e. compensation) and a decrease after positive feedback (i.e. modesty effect). In contrast, low identifiers distanced themselves from the ingroup after negative feedback and accentuated self-ingroup similarity after positive feedback. Results are discussed in relation to a schema-maintenance model through compensation (Seta & Seta, 1993) and social identity theory. Copyright © 2001 John Wiley & Sons, Ltd. [source] Conflicting phylogenetic signals at the base of the metazoan treeEVOLUTION AND DEVELOPMENT, Issue 4 2003Antonis Rokas Summary A phylogenetic framework is essential for under-standing the origin and evolution of metazoan development. Despite a number of recent molecular studies and a rich fossil record of sponges and cnidarians, the evolutionary relationships of the early branching metazoan groups to each other and to a putative outgroup, the choanoflagellates, remain uncertain. This situation may be the result of the limited amount of phylogenetic information found in single genes and the small number of relevant taxa surveyed. To alleviate the effect of these analytical factors in the phylogenetic recons-truction of early branching metazoan lineages, we cloned multiple protein-coding genes from two choanoflagellates and diverse sponges, cnidarians, and a ctenophore. Comparisons of sequences for ,-tubulin, ,-tubulin, elongation factor 2, HSP90, and HSP70 robustly support the hypothesis that choanoflagellates are closely affiliated with animals. However, analyses of single and concatenated amino acid sequences fail to resolve the relationships either between early branching metazoan groups or between Metazoa and choano-flagellates. We demonstrate that variable rates of evolution among lineages, sensitivity of the analyses to taxon selection, and conflicts in the phylogenetic signal contained in different amino acid sequences obscure the phylogenetic associations among the early branching Metazoa. These factors raise concerns about the ability to resolve the phylogenetic history of animals with molecular sequences. A consensus view of animal evolution may require investigations of genome-scale characters. [source] Problem Representation and Conflict Dynamics in the Middle East and Northern IrelandFOREIGN POLICY ANALYSIS, Issue 3 2005Donald A. Sylvan In an effort to explain conflictual and cooperative actions in the Middle East and Northern Ireland at a time (1995,1999) when international structural factors were relatively constant, this article focuses on cognitive factors. Specifically, statements of leaders representing multiple actors in the Israeli,Palestinian and Northern Ireland relationship are examined. Texts from these leaders serve as data for the independent variable, problem representation. Hypotheses argue that the existence and centrality of actor problem representations can help explain behavior, in a manner that adds to more widely used scholarly explanations. More specifically, the article explores the relationship among leaders' "problem representations" and conflict between the entities they lead. Problem representation is measured in three dimensions using Foreign Broadcast Information Service (World News Connection) texts: (1) centrality of enemy image, (2) how inclusive/exclusive the leader is in describing the in-group and principal outgroup, and (3) the key definition of the problem (coded in terms of three strategies: justice, governance, or threat). Conflict, the dependent variable, is measured in terms of KEDS-TABARI event data on deeds (not words) in the Israeli,Palestinian and Northern Ireland conflicts. Strikingly, the analysis finds that Israeli actions are strongly related to prior and current Palestinian leaders' problem representations, much more than they are to Israeli leaders' problem representations. Similarly, Palestinian actions are found to have a clear relationship with prior and current Israeli leaders' problem representations, much more than they are with Palestinian leaders' problem representations. These results are particularly strong when the problem representation is one of the overall political leadership on the "other" side. Additionally, in-group and out-group inclusivity are the most significant predictors of actions. For Northern Ireland, the same two themes prevail, although not as strongly: there is a clear statistical relationship between each side's problem representations and the other side's actions, stronger in fact than the relationship between their own side's representations and actions. Also, in-group and out-group inclusivity produce a strong statistical relationship with conflict and cooperation. Finally, results are compared with a "tit-for-tat" hypothesis, and found to embellish that hypothesis. [source] Geobiological analysis using whole genome-based tree building applied to the Bacteria, Archaea, and EukaryaGEOBIOLOGY, Issue 1 2003Christopher H. House ABSTRACT We constructed genomic trees based on the presence and absence of families of protein-encoding genes observed in 55 prokaryotic and five eukaryotic genomes. There are features of the genomic trees that are not congruent with typical rRNA phylogenetic trees. In the bacteria, for example, Deinococcus radiodurans associates with the Gram-positive bacteria, a result that is also seen in some other phylogenetic studies using whole genome data. In the Archaea, the methanogens plus Archaeoglobus form a united clade and the Euryarchaeota are divided with the two Thermoplasma genomes and Halobacterium sp. falling below the Crenarchaeota. While the former appears to be an accurate representation of methanogen-relatedness, the misplacement of Halobacterium may be an artefact of parsimony. These results imply the last common ancestor of the Archaea was not a methanogen, leaving sulphur reduction as the most geochemically plausible metabolism for the base of the archaeal crown group. It also suggests that methanogens were not a component of the Earth's earliest biosphere and that their origin occurred sometime during the Archean. In the Eukarya, the parsimony analysis of five Eukaryotes using the Crenarchaeota as an outgroup seems to counter the Ecdysozoa hypothesis, placing Caenorhabditis elegans (Nematoda) below the common ancestor of Drosophila melanogaster (Arthropoda) and Homo sapiens (Chordata) even when efforts are made to counter the possible effects of a faster rate of sequence evolution for the C. elegans genome. Further analysis, however, suggests that the gene loss of ,animal' genes is highest in C. elegans and is obscuring the relationships of these organisms. [source] Resolution of phylogenetic relationships of the major subfamilies of the Delphacidae (Homoptera: Fulgoroidea) using the mitochondrial ribosomal DNAINSECT SCIENCE, Issue 3 2006EDDY DIJKSTRA Abstract Delphacid relationships from the genus level to the subfamily have been completely resolved (among those taxa examined) using sequence data from the 3'end of the 12S gene. Monophyly of the non-asiracine subfamilies was strongly supported and the asiracine Ugyops was placed in the most basal position of the tree. Support levels for monophyly of the Delphacini increased after weighting transversions more heavily than transitions and after removing the cixiid outgroup from the dataset. Among the Delphacini, Conomelus and Megamelus were more closely related to each other than either was to Chloriona. These results are in agreement with the tree based on morphological characters. However, in contrast to morphological data our results strongly supported a sister group relationship between the Stenocraninae and the Kelisiinae. Although the 12S gene fragment gave some information about the species relationships within Chloriona, neither this fragment nor the 5'end of the 16S gene appear to be very useful for this level. Molecular evolutionary patterns provided evidence that there has been a shift in base composition from T to A during the early evolution of the non-Asiracinae. The non-Asiracinae also had comparatively fast substitution rates and these two observations are possibly correlated. In the ,modern' delphacid Chloriona, the AT content was comparatively low in regions free of constraints but this was not the case for ,non-modern' delphacids. The tRNA for valine has been translocated elsewhere, probably before the Delphacidae and Cixiidae diverged from each other. [source] Could stereotype rebound affect aid advertising campaigns?INTERNATIONAL JOURNAL OF NONPROFIT & VOLUNTARY SECTOR MARKETING, Issue 2 2009Sharyn Kennedy The possibility that stereotype rebound may occur for viewers of aid agency appeals was investigated. Stereotype rebound refers to the ironic finding that active efforts to avoid thinking about people in a stereotypical manner can backfire and subsequently lead to increased stereotypical thinking and prejudiced behaviour. In two experiments, participants were instructed to avoid stereotyped thinking about developing world poor and were later asked to respond to a situation involving the same group,in Experiment 1, participants wrote a ,day in the life' story about the target group; in Experiment 2, participants seated themselves in preparation for meeting a member of the outgroup. In neither experiment was the typical stereotype rebound effect observed. In Experiment 1, suppressors' stories were found to be no more stereotypical in content than controls. In Experiment 2, suppressors sat closer to the target than controls. The differences between these results and those of experiments utilizing other stereotyped groups are discussed in terms of differences in stereotype content and attitudes to socially sensitive outgroups. Copyright © 2008 John Wiley & Sons, Ltd. [source] Social group norms, school norms, and children's aggressive intentionsAGGRESSIVE BEHAVIOR, Issue 3 2010Christian Nipedal Abstract This study examined whether the effect of social group norms on 7- and 10-year-old children's aggression can be moderated or extinguished by contrary school norms. Children (n=384) participated in a simulation in which they were assigned membership in a social group for a drawing competition against an outgroup. Participants learnt that their group had a norm of inclusion, exclusion, or exclusion-plus-relational aggression, toward non-group members, and that the school either had a norm of inclusion, or no such norm. Findings indicated that group norms influenced the participants' direct and indirect aggressive intentions, but that the school norm moderated the group norm effect, with the school's norm effect tending to be greater for indirect vs. direct aggression, males vs. females, and younger vs. older participants. Discussion focused on how school norms can be developed, endorsed, and presented so that they have their most lasting effect on children. Aggr. Behav. 36:195,204, 2010. © 2010 Wiley-Liss, Inc. [source] Group membership, group norms, empathy, and young children's intentions to aggressAGGRESSIVE BEHAVIOR, Issue 3 2009Drew Nesdale Abstract This study assessed the effect of ingroup norms and empathy on 6 and 9-year-old children's (N=161) attitudes and aggressive intentions toward outgroup members. Prior to an intergroup drawing competition against an outgroup, participants' empathy was measured, and they were randomly assigned to a simulated group with a norm of direct or indirect aggression, or no aggression norm. Results indicated participants' attitudes were less positive toward the outgroup vs. the ingroup, and that both direct and indirect aggressive intentions were displayed toward the outgroup. Most importantly, the ingroup was liked less when it had an aggression norm, and the participants' aggressive intentions were not enhanced by the group aggression norm. Empathy was a significant negative predictor of direct but not indirect aggression intentions. Implications for understanding the instigation and inhibition of children's aggression intentions are discussed. Aggr. Behav. 35:244,258, 2009. © 2009 Wiley-Liss, Inc. [source] Skull shape and feeding strategy in Sphenodon and other Rhynchocephalia (Diapsida: Lepidosauria),JOURNAL OF MORPHOLOGY, Issue 8 2008Marc E.H. Jones Abstract The Rhynchocephalia are a group of small diapsid reptiles that were globally distributed during the early Mesozoic. By contrast, the only extant representatives, Sphenodon punctatus and S. guntheri (Tuatara), are restricted to New Zealand off-shore islands. The Rhynchocephalia are widely considered to be morphologically uniform but research over the past 30 years has revealed unexpected phenotypic and taxonomic diversity. Phylogenetically "basal taxa" generally possess relatively simple conical or columnar teeth whereas more derived taxa possessed stouter flanged teeth and sophisticated shearing mechanisms: orthal in some (e.g., Clevosaurus hudsoni) and propalinal in others (e.g., S. punctatus). This variation in feeding apparatus suggests a wide range of feeding niches were exploited by rhynchocephalians. The relationship of skull shape to skull length, phylogenetic grouping, habit, and characters relating to the feeding apparatus are explored here with geometric morphometric analysis on two-dimensional landmarks. Principle components analysis demonstrates that there are significant differences between phylogenetic groups. In particular, Sphenodon differs significantly from all well known fossil taxa including the most phylogenetically basal forms. Therefore, it is not justifiable to use Sphenodon as a solitary outgroup when studying skull shape and feeding strategy in squamates; rhynchocephalian fossil taxa also need to be considered. There are also significant differences between the skull shapes of aquatic taxa and those of terrestrial taxa. Of the observed variation in skull shape, most variation is subsumed by variation in dentary tooth base shape, the type of jaw movement employed (e.g., orthal vs. propalinal) and the number of palatal tooth rows. By comparison, the presence or absence of flanges, dentary tooth number and palatal tooth row orientation subsume much less. Skull length was also found to be a poor descriptor of overall skull shape. Compared to basal rhynchocephalians members of more derived terrestrial radiations possess an enlarged postorbital area, a high parietal, and a jaw joint positioned ventral to the tooth row. Modification of these features is closely associated with increased biting performance and thus access to novel food items. Some of these same trends are apparent during Sphenodon ontogeny where skull growth is allometric and there is evidence for ontogenetic variation in diet. J. Morphol., 2008. © 2008 Wiley-Liss, Inc. [source] Systematic positions of Lamiophlomis and Paraphlomis (Lamiaceae) based on nuclear and chloroplast sequencesJOURNAL OF SYSTEMATICS EVOLUTION, Issue 6 2009Yue-Zhi PAN Abstract, Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.l. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the literature. In the present paper, the systematic positions of Lamiophlomis, Paraphlomis, and their related genera were assessed based on nuclear internal transcribed spacer (ITS) and chloroplast rpl16 and trnL-F sequence data using maximum parsimony (MP) and Bayesian methods. In total, 24 species representing six genera of the ingroup and outgroup were sampled. Analyses of both separate and combined sequence data were conducted to resolve the systematic relationships of these genera. The results reveal that Lamiophlomis is nested within Phlomis sect. Phlomoides and its generic status is not supported. With the inclusion of Lamiophlomis rotata in sect. Phlomoides, sections Phlomis and Phlomoides of Phlomis were resolved as monophyletic. Paraphlomis was supported as an independent genus. However, the resolution of its monophyly conflicted between MP and Bayesian analyses, suggesting the need for expended sampling and further evidence. [source] Mitochondrial DNA control region diversity in the endangered blue chaffinch, Fringilla teydeaMOLECULAR ECOLOGY, Issue 9 2000J. Pestano Abstract The blue chaffinch (Fringilla teydea) is found only on the two central Canary Islands of Gran Canaria and Tenerife, where it is restricted to pine forest habitat. It is reasonably abundant on the latter island but endangered on the former. Here, sequence variation was studied in a fragment spanning domains I and II of the mitochondrial DNA (mtDNA) control region. Phylogenetic analysis of all haplotypes with a F. coelebs outgroup indicated the two island populations were reciprocally monophyletic, supporting their individual conservation. Unlike in other species, most within-island haplotype diversity was due to mutations in the domain II region. Surprisingly, genetic diversity was greater in the smaller Gran Canarian population. We suggest that this is unlikely to be maintained under current population sizes although it may be mitigated by incorporating genetic information into the captive breeding programme. [source] NEW CLADID AND FLEXIBLE CRINOIDS FROM THE MISSISSIPPIAN (TOURNAISIAN, IVORIAN) OF ENGLAND AND WALESPALAEONTOLOGY, Issue 5 2007THOMAS W. KAMMER Abstract:, The modern study of fossil crinoids began with J. S. Miller who, in 1821, described specimens from southern England, nearby Wales and other regions, and named several common Early Carboniferous genera. Later, in 1950,60, James Wright monographed all known Early Carboniferous crinoids from the British Isles. In spite of such previous scrutiny, we recognize here two new genera among species already described: Glamorganocrinus gen. nov. (type species: Ophiurocrinus gowerensis Wright, 1960) from South Wales and Mendipocrinus gen. nov. (type species: Poteriocrinus latifrons Austin and Austin, 1847) from southern England. These new genera increase the number of advanced cladid genera in the Ivorian Substage of the Tournaisian in western Europe to 18, and the total number of crinoid genera to 36. A review of species assigned to Mespilocrinus has led to the recognition of M. granulifer De Koninck and LeHon, 1854 as a nomen dubium. A new species of Mespilocrinus, M. wrighti sp. nov., is described from the Ivorian of South Wales; this is the most highly derived species of the genus, as based on a phylogenetic analysis including ten species and 13 characters, with Pycnosaccus as the outgroup. A single, well-ordered tree resulted from this analysis. Interpretation of this tree suggests that the centre of evolution for Mespilocrinus was North America, where three species appeared during the Kinderhookian (early Tournaisian), rapidly achieving morphological disparity within the genus. This radiation event was part of the overall explosive radiation of crinoids following the Late Devonian mass extinction event when crinoid diversity was at a global minimum during the Frasnian. Recovery began during the Famennian, followed by an explosive radiation in the Tournaisian. [source] Political Conservatism, Need for Cognitive Closure, and Intergroup HostilityPOLITICAL PSYCHOLOGY, Issue 4 2010Agnieszka Golec De Zavala Two studies examined the interaction of political conservatism and the need for cognitive closure in predicting aggressiveness in intergroup conflict and hostility toward outgroups. In the first study, Polish participants indicated their preference for coercive conflict strategies in the context of a real-life intergroup conflict. Only among participants who identify themselves as conservative, need for cognitive closure was positively and significantly related to preference for aggressive actions against the outgroup. In the second study, the predicted interaction was investigated in the context of the terrorist threat in Poland. The findings indicated that high in need for closure conservatives showed greater hostility against Arabs and Muslims only when they believed that Poland was under threat of terrorist attacks inspired by Islamist fundamentalism. [source] When and How Do High Status Group Members Offer Help: Effects of Social Dominance Orientation and Status ThreatPOLITICAL PSYCHOLOGY, Issue 6 2008Samer Halabi The present study explored the implications of an intergroup perspective on individual difference and situational influences on helping, specifically, outgroup members. In particular, we examined the effects of social dominance orientation (SDO) and group status threat on the amount and kind of help offered by Jewish participants (n = 99) to Arab and Jewish students. Dependent measures were the likelihood of helping outgroup and ingroup members across various situations of need and, when help is given, the likelihood that it would be dependency-oriented rather than autonomy-oriented assistance. As expected, higher SDO individuals offered less help to outgroup (Arab) students, particularly when they experienced threat to group status, but not to ingroup members. In addition, higher SDO participants, when they did report that they would help, were more likely to offer dependency-oriented help to outgroup than to ingroup members. The theoretical and applied implications are discussed. [source] Are behavioral differences among wild chimpanzee communities genetic or cultural?AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010An assessment using tool-use data, phylogenetic methods Abstract Over the last 30 years it has become increasingly apparent that there are many behavioral differences among wild communities of Pan troglodytes. Some researchers argue these differences are a consequence of the behaviors being socially learned, and thus may be considered cultural. Others contend that the available evidence is too weak to discount the alternative possibility that the behaviors are genetically determined. Previous phylogenetic analyses of chimpanzee behavior have not supported the predictions of the genetic hypothesis. However, the results of these studies are potentially problematic because the behavioral sample employed did not include communities from central Africa. Here, we present the results of a study designed to address this shortcoming. We carried out cladistic analyses of presence/absence data pertaining to 19 tool-use behaviors in 10 different P. troglodytes communities plus an outgroup (P. paniscus). Genetic data indicate that chimpanzee communities in West Africa are well differentiated from those in eastern and central Africa, while the latter are not reciprocally monophyletic. Thus, we predicted that if the genetic hypothesis is correct, the tool-use data should mirror the genetic data in terms of structure. The three measures of phylogenetic structure we employed (the Retention Index, the bootstrap, and the Permutation Tail Probability Test) did not support the genetic hypothesis. They were all lower when all 10 communities were included than when the three western African communities are excluded. Hence, our study refutes the genetic hypothesis and provides further evidence that patterns of behavior in chimpanzees are the product of social learning and therefore meet the main condition for culture. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc. [source] Analysis of mitochondrial DNA diversity in Burkina Faso populations confirms the maternal genetic homogeneity of the West African goatANIMAL GENETICS, Issue 3 2009L. J. Royo Summary To date, no comprehensive study has been performed on mitochondrial genetic diversity of the West African goat. Here, we analysed a 481-bp fragment of the HVI region of 111 goats representing four native West African populations, namely the three main Burkina Faso breeds, zoo-farm kept Dwarf goats and endangered Spanish goat breeds used as the outgroup. Analyses gave 83 different haplotypes with 102 variable sites. Most haplotypes (65) were unique. Only three haplotypes were shared between populations. Haplotypes were assigned to cluster A except for H45 (belonging to the Spanish Bermeya goat) which was assigned to cluster C. amova analysis showed that divergence between groups (,CT) was not statistically significant regardless of whether the partition in two hierarchical levels that was fitted included Spanish samples or not. The West African goat scenario shown here is consistent with that previously reported for the species: haplogroup A is predominant and has a very high haplotype diversity regardless of the geographic area or sampled breed. The large phenotypic differences observable between the West African Dwarf and Sahelian long-legged goat populations are not detectable with mitochondrial markers. Moreover, a previously suggested introgression of Sahelian goat southwards because of desertification could not be assessed using mtDNA information. [source] Temporal genetic heterogeneity of juvenile orange-spotted grouper (Epinephelus coioides, Pisces: Serranidae)AQUACULTURE RESEARCH, Issue 10 2009Panuwat Pumitinsee Abstract Juveniles of orange-spotted grouper (Epinephelus coioides), a tropical serranid species, are heavily harvested for aquaculture seeds from nursing grounds in several Southeast Asian countries. Because juveniles of similar sizes are present in a nursery area throughout the year, we aimed to determine whether more than one genetically distinct population contributes to juvenile aggregations. We examined the temporal genetic heterogeneity of juvenile aggregations collected at four different times of the year at a nursery area in coastal waters of the Andaman Sea in Trang province, Thailand. Also, we examined the differences between these temporal samples and an outgroup collected from the Gulf of Thailand (Chantaburi). The genetic variation at six polymorphic microsatellite loci within each sample was moderate, with observed heterozygosities across all loci ranging from 0.551 to 0.629 and number of alleles per locus ranging from 7.0 to 8.33. Results indicated substantial genetic differences between the two geographically distant samples, Trang and Chantaburi (Fst=0.040,0.050, P<0.005), and between the July sample and the remaining samples from Trang (Fst=0.096,0.106, P<0.005). The observed temporal genetic heterogeneity of E. coioides juveniles may reflect high variability in the reproductive success of each spawning event and the existence of spatially isolated groups of spawners. [source] | |||||||||||||||||||||||||||||||||||||||||||