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Official information about cancer and cancer clusters from state health departments clashes with lay views. A few studies have covered site-specific communication by telephone and public meetings, and hypothetical messages, but not generic information actually provided. Public response to such information was probed with a random survey of New Jersey households (n = 327), part of a quasi-experiment contrasting the agency's cognitive message and an alternative message adding procedural and affective information. Respondents rated both information types as understandable, helpful, and trustworthy, particularly among those trusting the agency, agreeing with officials’ views of facts, and with low concern about local clusters. Anxiety about cancer, aversion to uncertainty, cancer experience, and familiarity with clusters or the agency did not affect responses. Agreeing with officially defined facts (knowledge) was associated with trust in the agency and concern about clusters, but scepticism about expert knowledge. Information exposure increased trust, belief in expert knowledge (except on whether cancers cluster), and (some) factual knowledge, but also increased self-reported concern among those already concerned. These findings suggest that, absent specific learning, people believe scientific information is understandable, helpful, and trustworthy when they already trust experts and institutions; people with prior distrust offer less positive evaluations. 相似文献
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Beginning in the 1960s the first systematic projects dedicated to testing whether great apes could acquire some aspects of human language were conducted. The ape subjects demonstrated remarkable capacities to learn and use elements of either sign language or an artificial language. The results from research across several laboratories drew a mixture of excitement and skepticism, and critiques and debates have ensued since the earliest reports were published. This continues today. Terrace (2019, Nim: A chimpanzee who learned sign language. New York, NY: Columbia University Press) repeats many of the same points made decades earlier, and has added some additional critiques. That scientists hold different perspectives on what to conclude from ape language studies is expected. However, any conclusion one draws should be based upon available evidence, which we outline in this review. We also address the critiques offered by Terrace (2019), including the stance that apes cannot understand or use words. Focusing on symbol use by chimpanzees and bonobos we describe evidence that argues for understanding of words, including capacities for declarative communication and intersubjectivity found in these apes. We conclude that the many decades of research using a variety of symbol systems challenges the absolutist position that chimpanzees and bonobos cannot learn language or understand the concept of a word. 相似文献
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Eben Goodale Hari Sridhar Kathryn E. Sieving Priti Bangal Gabriel J. Colorado Z. Damien R. Farine Eckhard W. Heymann Harrison H. Jones Indrikis Krams Ari E. Martínez Flavia Montao‐Centellas Jenny Muoz Umesh Srinivasan Anne Theo Kartik Shanker 《Biological reviews of the Cambridge Philosophical Society》2020,95(4):889-910
Mixed‐species animal groups (MSGs) are widely acknowledged to increase predator avoidance and foraging efficiency, among other benefits, and thereby increase participants' fitness. Diversity in MSG composition ranges from two to 70 species of very similar or completely different phenotypes. Yet consistency in organization is also observable in that one or a few species usually have disproportionate importance for MSG formation and/or maintenance. We propose a two‐dimensional framework for understanding this diversity and consistency, concentrating on the types of interactions possible between two individuals, usually of different species. One axis represents the similarity of benefit types traded between the individuals, while the second axis expresses asymmetry in the relative amount of benefits/costs accrued. Considering benefit types, one extreme represents the case of single‐species groups wherein all individuals obtain the same supplementary, group‐size‐related benefits, and the other extreme comprises associations of very different, but complementary species (e.g. one partner creates access to food while the other provides vigilance). The relevance of social information and the matching of activities (e.g. speed of movement) are highest for relationships on the supplementary side of this axis, but so is competition; relationships between species will occur at points along this gradient where the benefits outweigh the costs. Considering benefit amounts given or received, extreme asymmetry occurs when one species is exclusively a benefit provider and the other a benefit user. Within this parameter space, some MSG systems are constrained to one kind of interaction, such as shoals of fish of similar species or leader–follower interactions in fish and other taxa. Other MSGs, such as terrestrial bird flocks, can simultaneously include a variety of supplementary and complementary interactions. We review the benefits that species obtain across the diversity of MSG types, and argue that the degree and nature of asymmetry between benefit providers and users should be measured and not just assumed. We then discuss evolutionary shifts in MSG types, focusing on drivers towards similarity in group composition, and selection on benefit providers to enhance the benefits they can receive from other species. Finally, we conclude by considering how individual and collective behaviour in MSGs may influence both the structure and processes of communities. 相似文献
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Mnica Arias Marianne Elias Christine Andraud Serge Berthier Doris Gomez 《Journal of evolutionary biology》2020,33(2):247-252
Predation is a ubiquitous and strong selective pressure on living organisms. Transparency is a predation defence widespread in water but rare on land. Some Lepidoptera display transparent patches combined with already cryptic opaque patches. A recent study showed that transparency reduced detectability of aposematic prey with conspicuous patches. However, whether transparency has any effect at reducing detectability of already cryptic prey is still unknown. We conducted field predation experiments with free avian predators where we monitored and compared survival of a fully opaque grey artificial form (cryptic), a form including transparent windows and a wingless artificial butterfly body. Survival of the transparent forms was similar to that of wingless bodies and higher than that of fully opaque forms, suggesting a reduction of detectability conferred by transparency. This is the first evidence that transparency decreases detectability in cryptic terrestrial prey. Future studies should explore the organization of transparent and opaque patches in animals and their interplay on survival, as well as the costs and other potential benefits associated with transparency on land. 相似文献
88.
Chang Ge Huakang Sheng Xin Chen Xiaolin Shen Xinxiao Sun Yajun Yan Jia Wang Qipeng Yuan 《Biotechnology journal》2020,15(6)
Quorum sensing (QS) is a ubiquitous cell–cell communication mechanism in microbes that coordinates population‐level cell behaviors, such as biofilm production, virulence, swarming motility, and bacterial persistence. Efforts to engineer QS systems to take part in metabolic network regulation represent a promising strategy for synthetic biology and pathway engineering. Recently, design, construction, and implementation of QS circuits for programmed control of bacterial phenotypes and metabolic pathways have gained much attention, but have not been reviewed recently. In this article, the architectural organizations and genetic contributions of the naturally occurring QS components to understand the mechanisms are summarized. Then, the most recent progress in application of QS toolkits to develop synthetic networks for novel cell behaviors creation and metabolic pathway engineering is highlighted. The current challenges in large‐scale application of these QS circuits in synthetic biology and metabolic engineering fields are discussed and future perspectives for further engineering efforts are provided. 相似文献
89.
基于Web of Science(简称WoS)核心数据库检索了1998-2018年间百合属植物文献,利用CiteSpace软件从国家、机构、作者、期刊以及高被引文章等方面进行了文献计量学统计分析。1998-2018年间共发表百合属植物文章1 058篇,2006年后中国发表文章数量居榜首并呈波动增长,中国科学院发表的文章数量在研究机构中排名第一。排名前2位的作者均来自荷兰瓦赫宁根大学。发文量及影响力最大的期刊是Scientia Horticulturae。发文量前10位的研究百合属植物的文章80%属于基础科学和技术科学,研究热点集中于形态学、细胞和分子生物学方向。近5年被引频次最多的高被引论文集中在百合属植物活性物质的功能验证、活性成分及其在营养健康方面的功效等方向,这些领域成为百合属植物研究的新趋势。 相似文献
90.
Alida Frankline Hasiniaina Ute Radespiel Sharon E. Kessler Mamy Rina Evasoa Solofonirina Rasoloharijaona Blanchard Randrianambinina Elke Zimmermann Sabine Schmidt Marina Scheumann 《Ecology and evolution》2020,10(8):3784-3797
Acoustic phenotypic variation is of major importance for speciation and the evolution of species diversity. Whereas selective and stochastic forces shaping the acoustic divergence of signaling systems are well studied in insects, frogs, and birds, knowledge on the processes driving acoustic phenotypic evolution in mammals is limited. We quantified the acoustic variation of a call type exchanged during agonistic encounters across eight distinct species of the smallest‐bodied nocturnal primate radiation, the Malagasy mouse lemurs. The species live in two different habitats (dry forest vs. humid forest), differ in geographic distance to each other, and belong to four distinct phylogenetic clades within the genus. Genetically defined species were discriminated reliably on the phenotypic level based on their acoustic distinctiveness in a discriminant function analysis. Acoustic variation was explained by genetic distance, whereas differences in morphology, forest type, or geographic distance had no effect. The strong impact of genetics was supported by a correlation between acoustic and genetic distance and the high agreement in branching pattern between the acoustic and molecular phylogenetic trees. In sum, stochastic factors such as genetic drift best explained acoustic diversification in a social communication call of mouse lemurs. 相似文献