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241.
Between 1998 and 2006, twenty-seven states amended their constitutions to prohibit same sex marriage. The 2008 elections again saw three states with ballot measures aimed at banning gay marriage. This study examines the determinants of support for those measures in California and Florida, and includes a similar measure placed on the primary election ballot in California in 2000. Support is measured as the county-wide vote in favor of each gay marriage ban. A number of hypotheses are explored that examine the urban/rural nature of each county, as well as the political and demographic characteristics of county residents. It is suggested that states may be best viewed as relatively independent groupings of diverse subcultures, rather than as homogenous populations with a single political culture. The findings reported here indicate that a host of demographic, political and religious differences within each state influence residents’ votes on gay marriage bans.  相似文献   
242.
243.
What factors determine whether mixed-race individuals claim a biracial identity or a monoracial identity? Two studies examine how two status-related factors-race and social class-influence identity choice. While a majority of mixed-race participants identified as biracial in both studies, those who were members of groups with higher status in American society were more likely than those who were members of groups with lower status to claim a biracial identity. Specifically, (a) Asian/White individuals were more likely than Black/White or Latino/White individuals to identify as biracial and (b) mixed-race people from middle-class backgrounds were more likely than those from working-class backgrounds to identify as biracial. These results suggest that claiming a biracial identity is a choice that is more available to those with higher status.  相似文献   
244.
In 2008 a young man committed suicide while his webcam was running. 1,500 people apparently watched as the young man lay dying: when people finally made an effort to call the police, it was too late. This closely resembles the case of Kitty Genovese in 1964, where 39 neighbours supposedly watched an attacker assault and did not call until it was too late. This paper examines the role of internet mediation in cases where people may or may not have been good Samaritans and what their responsibilities were. The method is an intuitive one: intuitions on the various potentially morally relevant differences when it comes to responsibility between offline and online situations are examined. The number of onlookers, their physical nearness and their anonymity have no moral relevance when it comes to holding them responsible. Their perceived reality of the situation and ability to act do have an effect on whether we can hold people responsible, but this doesn’t seem to be unique to internet mediation. However the way in which those factors are intrinsically connected to internet mediation does seem to have a diminishing effect on responsibility in online situations.  相似文献   
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246.
The social brain undergoes developmental change during adolescence, and pubertal hormones are hypothesized to contribute to this development. We used fMRI to explore how pubertal indicators (salivary concentrations of testosterone, oestradiol and DHEA; pubertal stage; menarcheal status) relate to brain activity during a social emotion task. Forty‐two females aged 11.1 to 13.7 years underwent fMRI scanning while reading scenarios pertaining either to social emotions, which require the representation of another person’s mental states, or to basic emotions, which do not. Pubertal stage and menarcheal status were used to assign girls to early or late puberty groups. Across the entire sample, the contrast between social versus basic emotion resulted in activity within the social brain network, including dorsomedial prefrontal cortex (DMPFC), the posterior superior temporal sulcus, and the anterior temporal cortex (ATC) in both hemispheres. Increased hormone levels (independent of age) were associated with higher left ATC activity during social emotion processing. More advanced age (independent of hormone levels) was associated with lower DMPFC activity during social emotion processing. Our results suggest functionally dissociable effects of pubertal hormones and age on the adolescent social brain.  相似文献   
247.
Frequently studies of learning and memory measure a single focal behaviour; however it is likely that any learning paradigm will alter multiple behavioural traits in the same animal. We used video footage of the great pond snail (Lymnaea stagnalis), collected immediately prior to both training and testing for memory in response to operant conditioning to reduce aerial respiration, to measure two additional alternate behavioural traits: reducing the size of the pneumostome (breathing orifice) opening and shell tilt to cover the pneumostome. Typically, the training regime used here results in memory to reduce the number of breathing attempts lasting 24?h but not 72?h. However, memory duration when measured using the two additional behavioural traits differed significantly; shell tilt was short-lived lasting less than 1?h following training, whereas the reduction in pneumostome size was still apparent 72?h following training. Therefore, conclusions about the ability of L. stagnalis to retain memory in response to a single type of training regime will differ significantly depending on the focal behavioural trait measured. A significant correlation between the reduction in opening attempts and visible pneumostome area indicated that these behavioural traits are co-specialised, whereas pneumostome opening and shell tilt behaviour varied independently.  相似文献   
248.
The Bengalese finch (Lonchura striata var. domestica) is a species of songbird. Males sing courtship songs with complex note-to-note transition rules, while females discriminate these songs when choosing their mate. The present study uses serial reaction time (RT) to examine the characteristics of the Bengalese finches’ sequential behaviours beyond song production. The birds were trained to produce the sequence with an “A–B–A” structure. After the RT to each key position was determined to be stable, we tested the acquisition of the trained sequential response by presenting novel and random three-term sequences (random test). We also examined whether they could abstract the embedded rule in the trained sequence and apply it to the novel test sequence (abstract test). Additionally, we examined rule abstraction through example training by increasing the number of examples in baseline training from 1 to 5. When considered as (gender) groups, training with 5 examples resulted in no statistically significant differences in the abstract tests, while statistically significant differences were observed in the random tests, suggesting that the male birds learned the trained sequences and transferred the abstract structure they had learned during the training trials. Individual data indicated that males, as opposed to females, were likely to learn the motor pattern of the sequence. The results are consistent with observations that males learn to produce songs with complex sequential rules, whereas females do not.  相似文献   
249.
Non-human primates possess species-specific repertoires of acoustically distinct call types that can be found in adults in predictable ways. Evidence for vocal flexibility is generally rare and typically restricted to acoustic variants within the main call types or sequential production of multiple calls. So far, evidence for context-specific call sequences has been mainly in relation to external disturbances, particularly predation. In this study, we investigated extensively the vocal behaviour of free-ranging and individually identified Diana monkeys in non-predatory contexts. We found that adult females produced four vocal structures alone (‘H’, ‘L’, ‘R’ and ‘A’ calls, the latter consisting of two subtypes) or combined in non-random ways (‘HA’, ‘LA’ and ‘RA’ call combinations) in relation to ongoing behaviour or external events. Specifically, the concatenation of an introductory call with the most frequently emitted and contextually neutral ‘A’ call seems to function as a contextual refiner of this potential individual identifier. Our results demonstrate that some non-human primates are able to increase the effective size of their small vocal repertoire not only by varying the acoustic structure of basic call types but also by combining them into more complex structures. We have demonstrated this phenomenon for a category of vocalisations with a purely social function and discuss the implications of these findings for evolutionary theories of primate vocal communication.  相似文献   
250.
It has been speculated that cage mesh exerts a shaping influence on reaching behavior by captive apes, which is then misconstrued as pointing by human observers. Although this notion is clearly falsified by the pointing of captive language-trained apes—who point in the absence of intervening cage mesh—nevertheless, the degree to which cage mesh might influence pointing hand shapes by captive great apes in other housing environments remains relatively unexplored. We examined 259 pointing gestures displayed in archival footage from over 18 h of observation by three nonlanguage-trained chimpanzees housed at a biomedical research center. We coded points in relation to how close to the boundaries of the diamond-shaped cage mesh their points were displayed. We found that points with the whole hand were significantly more likely to be displayed away from the mesh boundaries, relative to points with the index finger or other single-digit points. However, points of each hand shape were displayed at each location, demonstrating that these physical parameters do not fully account for the number of fingers extended while pointing by chimpanzees.  相似文献   
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