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Selected AbstractsGenetic Data and the Listing of Species Under the U.S. Endangered Species ActCONSERVATION BIOLOGY, Issue 5 2007SYLVIA M. FALLON Acta de Especies en Peligro de E. U. A.; decisiones de enlistado; segmento poblacional distinto Abstract:,Genetic information is becoming an influential factor in determining whether species, subspecies, and distinct population segments qualify for protection under the U.S. Endangered Species Act. Nevertheless, there are currently no standards or guidelines that define how genetic information should be used by the federal agencies that administer the act. I examined listing decisions made over a 10-year period (February 1996,February 2006) that relied on genetic information. There was wide variation in the genetic data used to inform listing decisions in terms of which genomes (mitochondrial vs. nuclear) were sampled and the number of markers (or genetic techniques) and loci evaluated. In general, whether the federal agencies identified genetic distinctions between putative taxonomic units or populations depended on the type and amount of genetic data. Studies that relied on multiple genetic markers were more likely to detect distinctions, and those organisms were more likely to receive protection than studies that relied on a single genetic marker. Although the results may, in part, reflect the corresponding availability of genetic techniques over the given time frame, the variable use of genetic information for listing decisions has the potential to misguide conservation actions. Future management policy would benefit from guidelines for the critical evaluation of genetic information to list or delist organisms under the Endangered Species Act. Resumen:,La información genética se está convirtiendo en un factor influyente para determinar sí una especie, subespecie y segmentos poblacionales distintos califican para ser protegidos por el Acta de Especies en Peligro de E. U. A. Sin embargo, actualmente no hay estándares o lineamientos que definan como deben utilizar información genética las agencias federales que administran el acta. Examiné las decisiones de enlistado basadas en información genética tomadas en un período de 10 años (febrero 1996,febrero 2006). Hubo una amplia variación en los datos genéticos utilizados para informar las decisiones de enlistado en términos de cuáles genomas (mitocondrial vs. nuclear) fueron muestreados y el número de marcadores (o técnicas genéticas) y los loci evaluados. En general, las agencias federales identificaron diferencias genéticas entre unidades taxonómicas putativas o poblaciones dependiendo del tipo y cantidad de datos genéticos. Los estudios que se basaron en marcadores genéticos múltiples tuvieron mayor probabilidad de identificar distinciones, y esos organismos tuvieron mayor probabilidad de recibir protección, que los estudios basados en un solo marcador genético. Aunque los resultados pueden, en parte, reflejar la disponibilidad de técnicas genéticas para decisiones de enlistado en el período analizado, el uso variable de información genética para la toma de decisiones puede desinformar acciones de conservación. Las políticas de manejo futuras se beneficiarían de directrices para la evaluación crítica de información genética para enlistar o quitar de la lista a organismos bajo el Acta de Especies en Peligro. [source] The Prevalence of Lying in America: Three Studies of Self-Reported LiesHUMAN COMMUNICATION RESEARCH, Issue 1 2010Kim B. Serota This study addresses the frequency and the distribution of reported lying in the adult population. A national survey asked 1,000 U.S. adults to report the number of lies told in a 24-hour period. Sixty percent of subjects report telling no lies at all, and almost half of all lies are told by only 5% of subjects; thus, prevalence varies widely and most reported lies are told by a few prolific liars. The pattern is replicated in a reanalysis of previously published research and with a student sample. Substantial individual differences in lying behavior have implications for the generality of truth,lie base rates in deception detection experiments. Explanations concerning the nature of lying and methods for detecting lies need to account for this variation. L'importance du mensonge aux États-Unis : trois études de mensonges auto-déclarés Kim B. Serota, Timothy R. Levine, Franklin J. Boster Cette étude aborde la fréquence et la distribution des mensonges déclarés par la population adulte. Un sondage national a demandéà 1 000 adultes américains de déclarer le nombre de mensonges racontés dans une période de 24 heures. 60 % des sujets ont rapporté ne pas avoir dit de mensonge du tout et près de la moitié de ces mensonges sont racontés par 5 % des sujets. L'importance des mensonges varie donc largement et la plupart des mensonges déclarés sont formulés par un petit nombre de menteurs prolifiques. Cette tendance se retrouve également dans une nouvelle analyse de recherches déjà publiées et dans l'échantillon étudiant. Des différences individuelles importantes dans les comportements mensongers ont également des conséquences pour la généralité d'un taux de référence vérité,mensonge dans les expériences de détection de la tromperie. Les explications concernant la nature du mensonge et les méthodes de détection de mensonges doivent prendre en compte cette variation. Mots clés : tromperie, mensonge, différences individuelles The Prevalence of Lying in America: Three Studies of Self-Reported Lies Research Question: This study addresses the frequency and the distribution of reported lying in the adult population. Significance: In the deception literature, consensus is that most people lie on a daily basis. Yet this view is founded on very little empirical evidence. This research tests the question of lying prevalence. Method: Survey research techniques and descriptive analysis are used to establish base rates and frequency distributions for reported lying behavior. Data source: A national survey asked 1,000 U.S. adults to report the number of lies told in a 24 hour period. Cross-validation is provided by re-analysis of previously reported diary and experimental data and by replication using a sample of 225 students. Findings: The oft-repeated average (arithmetic mean) of one to two lies per day is replicated but the study finds the distribution is highly skewed. On a typical day, 60% of subjects report telling no lies at all, and almost half or all lies are told by only 5% of subjects; thus, prevalence varies widely and most reported lies are told by a few prolific liars. The pattern is replicated in the re-analysis of previously published research and with the student sample. Implications: The findings of a highly skewed distribution render the average number of lies per day misleading. Substantial individual differences in lying behavior also have implications for the generality of truth-lie base-rates in deception detection experiments. Explanations concerning the nature of lying and methods for detecting lies need to account for this variation. Keywords: deception, lies, lying, communication, individual differences Die Prävalenz von Lügen in Amerika. Drei Studien zu selbstberichteten Lügen Forschungsfrage: Diese Studie untersucht die Häufigkeit und Verteilung von Lügen in der erwachsenen Bevölkerung. Zentralität: In der Literatur zu Täuschung besteht Konsens darüber, dass Menschen täglich Lügen. Allerdings basiert diese Feststellung auf wenigen empirischen Daten. Diese Untersuchung testet die Frage nach der Prävalenz von Lügen. Methode: Umfrage und beschreibende Analyse wurden angewandt, um eine Basisrate und Häufigkeitsdistribution für selbstberichtetes Lügenverhalten zu gewinnen. Datenquelle: In einer nationalen Umfrage wurden 1.000 US-amerikanische Erwachsene zur Zahl der Lügen befragt, die sie in 24 Stunden erzählten. Validiert wurden diese Aussagen durch eine erneute Analyse von bereits dokumentierten Tagebuchdaten und Experimentaldaten und durch die Replikation mit einer Stichprobe von 225 Studierenden. Ergebnisse: Der oft wiederholte Durchschnitt (arithmetische Mittel) von ein bis zwei Lügen pro Tag wurde in der Studie repliziert, allerdings zeigte sich auch, dass diese Verteilung schief ist. 60% der Befragten gaben an, an einem typischen Tag keine Lügen zu erzählen, fast die Hälfte aller Lügen wird von nur 5% der Befragten erzählt; die Prävalenz variiert stark und die meisten der berichteten Lügen werden durch wenige produktive Lügner erzählt. Dieses Muster wurde bei einer erneuten Analyse von vorher publizierten Daten und in der Studentenstichprobe repliziert. Implikationen: Die Ergebnisse dieser stark schiefen Verteilung zeigen, dass die durchschnittliche Zahl von Lügen pro Tag irreführend ist. Substantielle individuelle Unterschiede im Lügenverhalten haben Implikationen für die Verallgemeinerbarkeit von Wahrheit-Lüge-Basisraten in Täuschungserfassungs-Experimenten. Erklärungen zur Natur von Lügen und Methoden zur Erfassung von Lügen müssen diese Variation bedenken. Schlüsselworte: Täuschung, Lüge, Lügen, Kommunikation, individuelle Unterschiede La Prevalencia de la Mentira en América: Tres Estudios de Auto-reportes de Mentiras Kim B. Serota, Timothy R. Levine, Franklin J. Boster Michigan State University The authors thank Deborah Kashy Resumen Este estudio trata sobre la frecuencia y la distribución de los reportes de las mentiras de la población adulta. Una encuesta nacional preguntó a 1,000 adultos Estadounidenses que reporten el número de mentiras contadas en un período de 24-horas. 60% de los sujetos reportaron que no dicen mentiras para nada, y casi la mitad son contadas por solo un 5% de los sujetos; así, la prevalencia varía enormemente y muchos reportaron que las mentiras son contadas por pocos mentirosos prolíficos. La pauta es replicada en el re-análisis de investigación previamente publicada y con una muestra de estudiantes. Las diferencias individuales sustanciales en el comportamiento mentiroso tienen implicaciones también para la generalidad del índice basado en la verdad-mentira en los experimentos de detección de decepción. Las explicaciones concernientes a la naturaleza de la mentira y los métodos de detección de mentiras necesitan responder a esta variación. Palabras Claves: decepción, mentiras, mentir, comunicación, diferencias individuales [source] Mothers' Trait Verbal Aggressiveness as a Predictor of Maternal and Child Behavior During Playtime InteractionsHUMAN COMMUNICATION RESEARCH, Issue 3 2008Steven R. Wilson This article explores associations between mothers' trait verbal aggressiveness (VA) and maternal and child behavior during playtime interactions. Forty mothers completed a 10-minute play period with one of their children (range = 3,8 years) and then responded to D. A. Infante and C. J. Wigley's (1986) trait VA scale. Mothers' trait VA was associated positively (r = .48) with their rate of directing and inversely (r =,.44) with their child's rated cooperation. Qualitative analyses of a subset (n = 8) of interactions suggest that mothers high in trait VA used directives to control the choice, rate, and duration of activities, and used physical negative touch along with directives, more than low-VA mothers. Behaviors associated with trait VA occur even during brief mother,child interactions in which triggers for aggressive behavior largely are absent. Résumé Le trait d,agressivité verbale des mères comme variable explicative des comportements maternels et infantiles lors d'interactions de jeu Cet article explore les associations entre le trait d,agressivité verbale (AV) des mères et le comportement maternel et infantile lors d'interactions de jeu. 40 mères ont participéà une période de jeu de 10 minutes avec l,un de leurs enfants (tranche d'âge = 3-8 ans) puis ont répondu à l'échelle de trait d'AV d,Infante et Wigley (1986). Le trait d'AV des mères fut associé positivement (r= 0,48) à leur taux de contrôle et inversement (r= -0,44) au taux de coopération de leur enfant. Des analyses qualitatives d,un sous-ensemble (n= 8) d'interactions donnent à penser que les mères au trait d,AV élevé ont fait usage de directives pour contrôle le choix, le rythme et la durée des activités et qu'elles ont utilisé le toucher physique négatif en même temps que les directives, plus que ne l,ont fait les mères au trait d'AV faible. Les comportements associés au trait d'AV surviennent même lors de brèves interactions mère-enfant au cours desquelles les déclencheurs de comportements agressifs étaient largement absents. Abstract Das Müttermerkmal verbale Aggression als Prädiktor für Mutter-Kind-Verhalten in spielerischen Interaktionen Dieser Artikel untersucht den Zusammenhang zwischen dem Müttermerkmal verbale Aggression (VA) und dem Mutter-Kind-Verhalten in spielerischen Interaktionen. 40 Mütter spielten 10 Minuten lang mit einem ihrer Kinder (zwischen 3-8 Jahren) und beantworteten dann die VA-Eigenschaftsskala nach Infante & Wigley (1986). Das Müttermerkmal VA war positiv assoziiert (r= .48) mit der Häufigkeit des führenden Eingreifens und umgekehrt assoziiert (r= -.44) mit der vom Kind beurteilten Kooperation. Qualitative Analysen eines Teils (n= 8) der Interaktionen deuten darauf hin, dass Mütter mit hoher VA führendes Eingreifen nutzen, um die Wahl, Häufigkeit und Dauer von Aktivitäten zu kontrollieren. Sie nutzten außerdem häufiger physisch negative Berührungen zusammen mit dem führenden Eingreifen als Mütter mit niedriger VA. Mit dem Merkmal VA verbundene Verhaltensweisen finden sogar in kurzen Mutter-Kind-Interaktionen statt bei denen Auslöser für aggressives Verhalten weitestgehend fehlen. Resumen El Rasgo de la Agresividad Verbal de las Madres como Vaticinador del Comportamiento Materno y del Niño Durante las Interacciones en el Recreo Este artículo explora la asociación entre el rasgo de agresividad verbal de las madres (VA) y el comportamiento maternal y del niño durante las interacciones en el recreo. Cuarenta madres completaron un período de 10-minutos de juego con uno de sus hijos (oscilando = 3-8 años) y luego respondieron a la escala sobre el rasgo VA de Infante y Wigley (1986). El rasgo VA de las madres fue asociado positivamente (r= .48) con el grado de direccionamiento e inversamente (r= -.44) con el grado de cooperación de su niño. Los análisis cualitativos de un subset (n= 8) de interacciones sugieren que las madres con rasgos altos de VA usaron directivas para controlar la selección, el tipo, y la duración de las actividades, y usaron el contacto físico negativo junto con directivas, más que las madres con rasgos bajos de VA. Los comportamientos asociados con el rasgo VA durante las interacciones breves entre la madre y su niño que provocan el comportamiento agresivo se encuentran mayormente ausentes. ZhaiYao Yo yak [source] Fluctuaciones Temporales en la Composición Floristica del Bosque Tropical Atlántico,BIOTROPICA, Issue 1 2001Samir Gonçalves Rolim ABSTRACT Temporal and spatial changes in floristic composition over a 15-year period in an Atlantic tropical forest in Brazil were analyzed. The data were recorded in five 0.5-ha (50 × 100 m) plots within a 22,000-ha forest reserve. In each plot, all stems ± 10 cm diameter at breast height (DBH) were repeatedly inventoried. The overall number of species among all plots was steady over time but changed within a given plot. In all plots, the proportion for the disappearance of species was 7 percent and that for immigration of new species into the plots was 9.5 percent. Approximately 65 percent of the disappearance occurred between 1986 and 1989, and 74 percent of the immigration happened after 1986. The observed changes in composition evidently were due to natural disturbance and climatic events, such as an unusual four-month drought. Disappearance of species from the plots did not denote regional extinction of those species, because they persisted elsewhere in the forest reserve. The changes in species composition within the plots and persistence outside them, however, indicated that large areas are required for in situ conservation of tropical tree species. These areas must be large enough for population changes to occur without negative effects on genetic and demographic structures of tree species. RESUMES Foram analisadas as variações temporais e espaciais na composição florística de uma floresta tropical num período de 15 anos entre os anos de 1980 e 1995. Em 5 parcelas de 0.5 ha (50 × 100 m) amostraram-se todas as árvores com diàmetro a altura do peito (DAP) , 10 cm. Para a escala e período que este estudo abrangeu pode-se concluir que há uma estabilidade no número de espécies da comunidade ao longo do tempo e esta estabilidade foi significativamente afetada por um distúrbio natural (um período seco de 4 meses) ocorrido em 1987. Foi constatado que em 15 anos desapareceram 7 por ciento das espécies nas parcelas monitoradas, contra um total de 9.5 por ciento de novas espécies recrutadas. Aproximadamente 65 por ciento do desaparecimento de espécies ocorreu entre 1986 e 1989 e 74 por ciento das novas espécies foram recrutadas apos 1986. O desaparecimento não significa necessariatmente um fenômeno de extinção e foi demonstrado que as espécies continuam ocorrendo na comunidade. O desaparecimento de espécies dentro das parcelas e sua pcrsisténcia fora delas indica que são necessárias grandes áreas para conservação in situ de espécies arbóreas. Estas áreas devem ser capazes de absorver as flutuaçz,oes populacionais sem afetar a estrutura genética e demográfica das espécies. [source] Terrestrial Small Mammal Richness and Habitat Associations in an Amazon Forest,Cerrado Contact Zone,BIOTROPICA, Issue 1 2001Thomas E. Lacher Jr. ABSTRACT The Amazon Forest and the Cerrado of central Brazil share an extensive zone of integration. Each of these major ecosystems remains poorly studied; however, the composition of communities at the contact zone is even less well described. Small mammals were sampled during a ten,week period in a zone of contact between Amazonian forest and Cerrado. The vegetation in the area was a complex mixture of tropical and semi,deciduous forest, and grassland and savanna woodland formations. Mammals were marked and recaptured on 0.25, to 0.5,km transects and vouchers were collected. A total of 19 species was caught (13 rodents and 6 marsupials) in 4621 trap nights. Transitions from one vegetation type to another were abrupt with ecotones frequently < 5 m in width. The highest a,diversity was 7 species in cerrado. Ten of the 19 species were restricted to one habitat and 6 were restricted to two habitats. Three generalist grassland species occurred in more than two habitats, all variations of savanna. These data support other research indicating high habitat specificity of vertebrates and plants in the Brazilian savannas. The diversity of habitats within reserves in tropical grasslands must be given consideration in the design of protected areas in order to maximize the conservation of mammalian biodiversity. RESUMES A floresta Amazônica e o Cerrado do Brasil Central compartilham uma zona extensa de integração. Estes ecossistemas são pouco estudados, e a composição das comunidades que ocorrem na zona de contato é ainda menos conhecida. Pequenos mamiferos foram capturados durance um período de 10 semanas em uma zona de contato entre a floresta Amazônica e o Cerrado. A vegetação desta área é um complexo de florestas semidecíduas e tropicais, campos e cerrados. Mamiferos foram capturados e marcados em transetos variando de 250 a 500 m; uma coleção de referênda também foi feita. Capturamos um total de 19 espécies (13 roedores e 6 marsupiais) em 4621 noitesarmadilhas. As transições entre tipos de vegetação foram abruptas com ecótonos frequentemente menores que 5 m de largura. O cerrado teve a a-diversidade mais alta: sete espécies. Dez das 19 espécies estavam restritas a um habitat e seis a dois habitats. Três espécies generalistas de savana ocorreram em mais de dois habitats, mas sempre em algum tipo de campo ou cerrado aberto. Estes dados corroboram com outras pesquisas indicando um alto nivel de especificidade de habitat para vertebrados e plantas no Cerrado. Consequentemente, para melhor preservar a diversidade de mamíferos no Brasil Central deve-se dar mais atenção à diversidade de habitats em áreas de proteção no Cerrado. [source] |