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11.
Variation in vocal behavior among local populations of songbirds may be significant to females in mate choice. In a study of dialect populations of brown-headed cowbirds, estradiol-implanted females from two dialects held the pre-copulatory lordosis posture longer in response to playback of the local flight whistle song than to foreign whistle types from adjacent and more distant dialects. Females were held in captivity for a relatively brief period prior to testing and received no tutoring so discrimination was based solely on experience in the wild. This is the first study to show evidence of discrimination by female cowbirds based on flight whistle type. Evidence is presented from one of the study dialects that the majority of yearling male cowbirds are vocally distinct from resident adults in having either foreign or incomplete local whistles. Although these yearlings are fully mature sexually, they have little or no mating success. The correlation between female whistle preference and male mating success suggests that the ability to give the correct local whistle type may be a characteristic used by females to assess age and quality of a potential mate. A learned female preference for the predominant local song type may be a factor in the stability of these dialects by making it adaptive for males to conform to the local dialect.  相似文献   
12.
The sexy son hypothesis suggests that females obtain future fitness benefits from mating with polygynous males through the inheritance by their sons of traits contributing to mating success. We tested this hypothesis in the facultatively polygynous European starling (Sturnus vulgaris) in two ways. We first compared sons of monogynous and polygynous free-living males for their abilities in nest site acquisition and female-directed behaviors in controlled aviary tests. We then investigated eggs laid in monogynous and polygynous matings for concentrations of maternal steroid hormones that could affect behavioral differentiation of sons. Sons of polygynous fathers defended more nest boxes and produced more courtship song than sons of monogynous fathers. Mean concentrations of maternal androstenedione (A4), 5-dihydrotestosterone (DHT), testosterone (T), and 17-estradiol (E) in yolks were not affected by mating status. However, the within-clutch pattern of A4 depended on mating status, with higher concentrations in last than in first eggs of clutches of monogynous but not polygynous matings. These results suggest that (1) sons may inherit from their fathers behavioral qualities for the successful acquisition of nest sites and attraction of mates; (2) differential exposure to maternal steroid hormones during development in the egg is unlikely the cause of the behavioral differences between adult sons of monogynous and polygynous fathers; and (3) females adjust the within-clutch pattern of androgen to mating status, possibly in response to the expected contribution of their mate to nestling care.  相似文献   
13.
INTRODUCTION: Train-pedestrian collisions have been shown to be the leading cause of fatality in train-related accidents worldwide, yet there is remarkably little research in this area. METHOD: In this paper, the major types of railway transportation accident research are briefly highlighted to indicate the general context of research concerning train-pedestrian collisions, which are then reviewed. Themes emerging from the diverse research are identified, the various strategies that have been proposed for prevention of railway pedestrian accidents are discussed, and the empirical evidence for their efficacy examined in the light of the much more extensive literature on road pedestrian accidents. Finally, it is proposed that application of current theory in behavioral and cognitive psychology may usefully inform future research in transportation safety.  相似文献   
14.
The queenless ant Pristomyrmex pungens has an unusual social structure, in which all workers reproduce parthenogenetically and help others. Laboratory experiments manipulating the proportion of post-reproductive foragers in the colony at various rates suggested that colonies with 5–10% forager ratios had the maximum efficiency per-worker. This result suggests that the cooperative colonies may be maintained by colony-level natural selection. Non-cooperative mutants that oviposit but do not forage should increase in relative frequency in the colony in the short term. However, decreased colony productivity and the resulting competition among colonies might eliminate colonies dominated by such mutants in the long term. P. pungens has a viscous population without migration between colonies, which may facilitate this process.  相似文献   
15.
人是一种精神性的存在者,其生命承载着多重性的价值.人不光具有自然价值,同时还具有精神价值.这正是人类优越于其它生命的地方.环境论理学的目的性理论,是把意识的价值还原到自然的价值上去.它肯定了生命的权利,具有积极的意义.另一方面,它也混淆了人的精神价值与自然价值的区别.  相似文献   
16.
Objective: Road accidents are an important public health concern, and speeding is a major contributor. Although flow theory (FLT) is a valid model for understanding behavior, currently the nature of the roles and interplay of FLT constructs within the theory of planned behavior (TPB) framework when attempting to explain the determinants of motivations for intention to speed and speeding behavior of car drivers is not yet known. The study aims to synthesize TPB and FLT in explaining drivers of advanced vehicles intentions to speed and speed violation behaviors and evaluate factors that are critical for explaining intention and behavior.

Method: The hypothesized model was validated using a sample collected from 354 fully licensed drivers of advanced vehicles, involving 278 males and 76 females on 2 occasions separated by a 3-month interval. During the first of the 2 occasions, participants completed questionnaire measures of TPB and FLT variables. Three months later, participants' speed violation behaviors were assessed.

Results: The study observed a significant positive relationship between the constructs. The proposed model accounted for 51 and 45% of the variance in intention to speed and speed violation behavior, respectively. The independent predictors of intention were enjoyment, attitude, and subjective norm. The independent predictors of speed violation behavior were enjoyment, concentration, intention, and perceived behavioral control.

Conclusions: The findings suggest that safety interventions for preventing speed violation behaviors should be aimed at underlying beliefs influencing the speeding behaviors of drivers of advanced vehicles. Furthermore, perceived enjoyment is of equal importance to driver's intention, influencing speed violation behavior.  相似文献   

17.
Introduction: This study performed a path analysis to uncover the behavioral pathways (from contributing factors, pre-crash actions to injury severities) in bicycle-motor vehicle crashes. Method: The analysis investigated more than 7,000 bicycle-motor vehicle crashes in North Carolina between 2007 and 2014. Pre-crash actions discussed in this study are actions of cyclists and motorists prior to the event of a crash, including “bicyclist failed to yield,” “motorist failed to yield,” “bicyclist overtaking motorist,” and “motorist overtaking bicyclist.” Results: Model results show significant correlates of pre-crash actions and bicyclist injury severity. For example, young bicyclists (18 years old or younger) are 23.5% more likely to fail to yield to motor traffic prior to the event of a crash than elder bicyclists. The “bicyclist failed to yield” action is associated with increased bicyclist injury severity than other actions, as this behavior is associated with an increase of 5.88 percentage points in probability of a bicyclist being at least evidently injured. The path analysis can highlight contributing factors related to risky pre-crash actions that lead to severe injuries. For example, bicyclists traveling on regular vehicle travel lanes are found to be more likely to involve the “bicyclist failed to yield” action, which resulted in a total 44.38% (7.04% direct effect + 37.34% indirect effect) higher likelihood of evident or severe injuries. The path analysis can also identify factors (e.g., intersection) that are not directly but indirectly correlated with injury severity through pre-crash actions. Practical Applications: This study offers a methodological framework to quantify the behavioral pathways in bicycle-motor vehicle crashes. The findings are useful for cycling safety improvements from the perspective of bicyclist behavior, such as the educational program for cyclists.  相似文献   
18.
水资源管理部门正在面临应对干旱,人口增长和水资源减少,气候变化的预言而仍要保证有足够水供应满足需求的挑战。为了发展有效的家庭需求管理程序,水资源管理者需要了解可能影响家庭水源使用的因素。通过检查和再分析当前的水消费行为模型,我们提出了一个理解家庭水消费的新模型。我们对信任在居民水消费中所发挥的作用进行了讨论,因为如果人们感觉身边的人并没有最小化水的使用那么人们便不会自觉节约用水(人际间的信任)。除此之外,如果人们不信任水资源管理部门,那么人们也不太可能节约用水(对社会公共机构的信任)。本文提出了为完全理解确定居民用水行为所涉及的因素,需要对水消费中信任度的作用进行研究。  相似文献   
19.
降低消费阶段的碳排放量对实现国家“双碳”战略目标具有重要意义。在此背景下,本研究从碳标签出发,引入“亲社会行为”这一变量,提出研究假设并构建了消费者低碳购买意愿的模型,利用调查问卷和结构方程模型进行数据分析,探究碳标签对消费者低碳购买意愿的影响,并分析亲社会行为在其中的调节作用。研究结果显示,碳标签认知、碳标签宣传均直接影响消费者的低碳购买意愿,碳标签公信力对低碳购买意愿没有直接影响;感知价值和购买态度在碳标签相关因素与低碳购买意愿之间起到完全或部分中介作用;亲社会行为在感知价值和购买态度对低碳购买意愿产生中介效应的链路上具有调节作用。基于研究结果,本文从提高消费者碳标签的认知水平、增强碳标签的宣传效果、提升碳标签的公信力、倡导亲社会的低碳行为等方面提出对策建议,以期通过政府、企业和消费者的多方努力,促进消费者积极参与低碳消费,实现消费领域的低碳变革。  相似文献   
20.
居民电子废物回收行为影响因素的实证研究   总被引:1,自引:1,他引:0       下载免费PDF全文
基于对350名城市居民的问卷调查结果,运用验证性因子分析方法对居民的电子废物回收行为、行为意向及其影响因素进行了实证研究.结果表明,基于计划行为理论所建立的结构方程模型可以较为有效地诠释有关研究假设,环境知识、舆论宣传和垃圾分类等情境因素对电子废物回收行为具有调节作用.知觉行为控制对于行为意向转化为行为具有非常重要地促进作用,而便利状况则是影响知觉行为控制的重要因素.  相似文献   
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