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161.
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
162.
Polder-Verkiel SE 《Science and engineering ethics》2012,18(1):117-141
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
163.
164.
Danielle Matthews Tanya Behne Elena Lieven Michael Tomasello 《Developmental science》2012,15(6):817-829
Despite its importance in the development of children’s skills of social cognition and communication, very little is known about the ontogenetic origins of the pointing gesture. We report a training study in which mothers gave children one month of extra daily experience with pointing as compared with a control group who had extra experience with musical activities. One hundred and two infants of 9, 10, or 11 months of age were seen at the beginning, middle, and end of this one‐month period and tested for declarative pointing and gaze following. Infants’ability to point with the index finger at the end of the study was not affected by the training but was instead predicted by infants’ prior ability to follow the gaze direction of an adult. The frequency with which infants pointed indexically was also affected by infant gaze following ability and, in addition, by maternal pointing frequency in free play, but not by training. In contrast, infants’ ability to monitor their partner’s gaze when pointing, and the frequency with which they did so, was affected by both training and maternal pointing frequency in free play. These results suggest that prior social cognitive advances, rather than adult socialization of pointing per se, determine the developmental onset of indexical pointing, but socialization processes such as imitation and adult shaping subsequently affect both infants’ ability to monitor their interlocutor’s gaze while they point and how frequently infants choose to point. 相似文献
165.
Susan Goldin‐Meadow Susan C. Levine Elena Zinchenko Terina KuangYi Yip Naureen Hemani Laiah Factor 《Developmental science》2012,15(6):876-884
Performing action has been found to have a greater impact on learning than observing action. Here we ask whether a particular type of action – the gestures that accompany talk – affect learning in a comparable way. We gave 158 6‐year‐old children instruction in a mental transformation task. Half the children were asked to produce a Move gesture relevant to the task; half were asked to produce a Point gesture. The children also observed the experimenter producing either a Move or Point gesture. Children who produced a Move gesture improved more than children who observed the Move gesture. Neither producing nor observing the Point gesture facilitated learning. Doing gesture promotes learning better than seeing gesture, as long as the gesture conveys information that could help solve the task. 相似文献
166.
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
167.
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
168.
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
169.
Although rats are able to build complex spatial representations of their surroundings during exploration, the nature of the
encoded information is still a matter for debate. In particular, it is not well established if rats can process the topological
structure of the environment in such a way that they are aware of the connections existing between remote places. Here, rats
were first exposed for four 5-min trials to a complex environment divided into several sectors that were separated by doors
allowing either unrestricted or restricted access to other sectors. In the fifth test trial, we measured the behavior of the
animals while they explored the same environment in which, however, they faced changes that either altered or did not alter
the topological structure of the environment. In experiment 1, closing previously opened doors prevented the rat from having
direct access between corresponding sectors. In experiment 2, opening previously closed doors allowed direct access between
sectors that had not been directly accessible. In each experiment, control doors allowed us to discard the mere influence
of door manipulation. We compared the rats’ exploratory behavior in response to door manipulations that either strongly altered
or did not alter the ability to commute between sectors and found evidence that the animals displayed differential reactions
to the two types of door manipulations. This implies that during exploration rats build a precise map of the connectivity
of space that can be flexibly updated and used for efficient navigation. 相似文献
170.
Uneconomical choices by humans or animals that evaluate reward options challenge the expectation that decision-makers always
maximize the return currency. One possible explanation for such deviations from optimality is that the ability to sense differences
in physical value between available alternatives is constrained by the sensory and cognitive processes for encoding profitability.
In this study, we investigated the capacity of a nectarivorous bat species (Glossophaga commissarisi) to discriminate between sugar solutions with different concentrations. We conducted a two-alternative free-choice experiment
on a population of wild electronically tagged bats foraging at an array of computer-automated artificial flowers that recorded
individual choices. We used a Bayesian approach to fit individual psychometric functions, relating the strength of preferring
the higher concentration option to the intensity of the presented stimulus. Psychometric analysis revealed that discrimination
ability increases non-linearly with respect to intensity. We combined this result with a previous psychometric analysis of
volume perception. Our theoretical analysis of choice for rewards that vary in two quality dimensions revealed regions of
parameter combinations where uneconomic choice is expected. Discrimination ability may be constrained by non-linear perceptual
and cognitive encoding processes that result in uneconomical choice. 相似文献