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231.
When birds raised by another species become adults, they (if they are non-brood-parasitic species) usually attempt to mate
with birds of their foster species rather than with birds of their own species, a phenomenon called sexual imprinting. Avian
brood parasites lay their eggs in nests of other species (the hosts) that rear the young, but the problem of sexual imprinting
among brood parasites has generally been neglected, and brood parasites have been considered as an exception among birds.
Here, we show, with data from field observations and field experiments, firstly, that adult great spotted cuckoos Clamator glandarius sometimes maintain contact with both older nestling and fledgling cuckoos. Adult cuckoos visited parasitized nests during
the last days of the nestling period (5 observations) and, when parasitic chicks left the nest, adult cuckoos maintained contact
with the young (14 observations). Adults and fledgling cuckoos communicated vocally (5 observations), and an adult great spotted
cuckoo even fed a parasite fledgling in two cases. Secondly, when experimentally cross-fostered in nests of magpie Pica pica hosts outside the parasite breeding range (thus avoiding visual and acoustic communication with adult cuckoos), young cuckoos
did not learn to recognize their own species when only one cuckoo chick was introduced per nest, but they learnt to recognize
conspecifics when two cuckoos were reared together. This means that young great spotted cuckoos apparently must learn to recognize
conspecifics, that is, recognition is not innate. Social interactions between adult brood parasites and young have also been
reported in other brood parasites; thus, brood parasites are probably not an exception to the general phenomenon of imprinting,
and young brood parasites may need to be imprinted on conspecifics, although more studies on other brood parasite species
are needed to confirm this.
Received: 7 January 1999 / Accepted after revision: 27 February 1999 相似文献
232.
Aimée M. Surprenant Susan L. Hura Mary P. Harper Leah H. Jamieson Glenis Long Scott M. Thede Ayasakanta Rout Tsung-Hsiang Hsueh Stephen A. Hockema Michael T. Johnson Pramila N. Srinivasan Christopher M. White J. Brandon Laflen 《Behavior research methods》1999,31(4):638-649
Ratings of familiarity and pronounceability were obtained from a random sample of 199 surnames (selected from over 80,000 entries in the Purdue University phone book) and 199 nouns (from the Ku?era-Francis, 1967, word database). The distributions of ratings for nouns versus names are substantially different: Nouns were rated as more familiar and easier to pronounce than surnames. Frequency and familiarity were more closely related in the proper name pool than the word pool, although both correlations were modest. Ratings of familiarity and pronounceability were highly related for both groups. A production experiment showed that rated pronounceability was highly related to the time taken to produce a name. These data confirm the common belief that there are differences in the statistical and distributional properties of words as compared to proper names. The value of using frequency and the ratings of familiarity and pronounceability for predicting variations in actual pronunciations of words and names are discussed. 相似文献
233.
The ESPbase provides a tool for storing symbols and icons along with information about their characteristics. Information about a wide range of symbol characteristics is included on the database to facilitate the selection of symbol sets for research and design. The database includes information about the graphical characteristics and functions of symbols. It also includes ratings of symbol concreteness, complexity, familiarity, and meaningfulness. Symbols and icons can be accessed on the basis of each of these characteristics or any combination of characteristics. This makes it easier to select symbols on the basis of usability and design requirements. It also means that symbols can be easily selected for research while controlling their characteristics on a number of dimensions. 相似文献
234.
In Pérez Laraudogoitia (1996), I introduced a simple example of a supertask that involved the possibility of spontaneous self-excitation
and, therefore, of a particularly interesting form of indeterminism in classical dynamics. Alper and Bridger (1998) criticised
(among other things) this result. In the present article, I answer their criticisms. In what follows I assume familiarity
both with Pérez Laraudogoitia (1996) and Alper and Bridger’s subsequent article.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
235.
17 subjects diagnosed with schizophrenia and having auditory hallucinations in their case history were compared with 15 control subjects in an experiment on perceptual restoration. A tone pattern was presented, then interrupted by noise, under conditions such that the tone pattern could be heard as going on continuously (restoration). A series of 16 stimuli with a distractor of varying amplitude (noise) were presented. Healthy controls reliably reported restoration in Presentations 9 and 10. Four schizophrenics reported no restoration at all. Three of them reported restoration earlier than controls, and four others reported it later than controls and continued to report the phenomenon after a point at which no healthy controls did. Six other presented an irregular pattern of response to the phenomenon. The results are discussed with respect to the neurophysiological functioning of the auditory pathway and schizophrenic symptoms. 相似文献
236.
Analysis of 1998 statistics for individual performance in the PGA European Tour yielded significant differences between some shot-making skills (drive distance, total driving, greens in regulation, and sand saves) between the top 10 and bottom 10 money winners, replicating (with partially different results) a result found for the 1995 American PGA Tour by Engelhardt. 相似文献
237.
Mentoring Relationship Closures in Big Brothers Big Sisters Community Mentoring Programs: Patterns and Associated Risk Factors 下载免费PDF全文
David J. DeWit David DuBois Gizem Erdem Simon Larose Ellen L. Lipman Renée Spencer 《American journal of community psychology》2016,57(1-2):60-72
Previous research suggests that early mentoring relationship (MR) closures may have harmful consequences for the health and well‐being of youth participating in community‐based mentoring programs. However, knowledge of the factors that lead some MRs to close early has been slow to emerge. This study examined patterns and correlates of early versus on‐time MR closures among 569 youth participating in Big Brothers Big Sisters community mentoring programs. Thirty‐four percent of youth experienced an early MR closure prior to the end of the program's 12 month period of commitment. The probability of closure was highest at 12 months into the MR. Early closures were positively associated with youth gender (girls), behavioral difficulties, and match determination difficulties. Early and on‐time closures were associated with youth extrinsic motives for joining the program. Early MR closures were negatively associated with youth perceptions of parent emotional support, parent social support, high quality MR, weekly contact in MR, and parent support of the MR. Implications for programming are discussed. 相似文献
238.
ResumenEn el presente trabajo se han empleado las medidas cronométricas de Tiempo de Inspección (TI) y Tiempo de Reacción (TR) para estudiar los efectos de las diferencias individuales en extroversion sobre una tarea de discriminación perceptual. Para ello se utilizaron dos grupos de sujetos que habían obtenido puntuaciones máximas y mínimas en la dimensión Extraversión del Test EPI de H. J. Eysenck. Se postuló que los extrovertidos obtendrían un TI más corto que los introvertidos y asimismo un TR también más corto, de acuerdo a los modelos de Brebner (1980) y Tous (1986). Los resultados indicaron que si bien existieron diferencias entre extrovertidos e introvertidos en cuanto a las medidas cronométricas, estas dit erencias dependieron del uso diferencial de estrategias de resolver la tarea que fueron utilizadas por estos sujetos. 相似文献
239.
Longitudinal trajectories of bicultural identity integration in recently immigrated Hispanic adolescents: Links with mental health and family functioning 下载免费PDF全文
Seth J. Schwartz Jennifer B. Unger Lourdes Baezconde‐Garbanati Verónica Benet‐Martínez Alan Meca Byron L. Zamboanga Elma I. Lorenzo‐Blanco Sabrina E. Des Rosiers Assaf Oshri Raha F. Sabet Daniel W. Soto Monica Pattarroyo Shi Huang Juan A. Villamar Karina M. Lizzi José Szapocznik 《International journal of psychology》2015,50(6):440-450
This study examined, in a sample of recently immigrated Hispanic adolescents in Miami and Los Angeles, the extent to which bicultural identity integration (BII; involving the ability to synthesise one's heritage and receiving cultural streams and to identify as a member of both cultures) is best understood as a developmental construct that changes over time or as an individual‐difference construct that is largely stable over time. We were also interested in the extent to which these trajectories predicted mental health and family functioning. Recent‐immigrant 9th graders (N = 302) were assessed 6 times from 9th to 12th grade. Latent class growth analyses using the first 5 timepoints identified 2 trajectory classes—one with lower BII scores over time and another with higher BII scores over time. Higher heritage and US identity at baseline predicted membership in the higher BII class. At the 6th study timepoint, lower BII adolescents reported significantly poorer self‐esteem, optimism, prosocial behaviour and family relationships compared with their higher BII counterparts. These findings are discussed in terms of further research on the over‐time trajectory of biculturalism, and on the need to develop interventions to promote BII as a way of facilitating well‐being and positive family functioning. 相似文献
240.
Réka Török István Tóth-Király Beáta Bőthe Gábor Orosz 《Current psychology (New Brunswick, N.J.)》2017,36(4):764-773
The goal of the study was to examine the dimensionality of the Career Decision Self-Efficacy Scale Short Form (CDSES-SF, Betz et al. 1996). Integrating several previous findings from different cultures, we found that the bifactor structure of the CDSES-SF on a Hungarian sample of 649 respondents showed the best model fit. This structure includes a general CDSE factor covering 15 items and the original five specific factors (self-appraisal, occupational information, goal selection, planning, and problem solving) covering three items each. This short form of CDSES shows an acceptable model fit and appropriate reliability in terms of the Cronbach’s alpha and omega values. Regarding career decision self-efficacy, a large proportion of variance was explained by the general factor and to a smaller extent by the specific factors. These results can be considered as a first step in resolving the paradox of the dimensionality of CDSES-SF. 相似文献