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101.
In this article we apply geodemographic consumer segmentation data in an input−output framework to understand the direct and indirect carbon dioxide (CO2) emissions associated with consumer behavior of different lifestyles in the United Kingdom. In a subsequent regression analysis, we utilize the lifestyle segments contained in the dataset to control for aspects of behavioral differences related to lifestyles in an analysis of the impact of various socioeconomic variables on CO2 emissions, such as individual aspirations and people's attitudes toward the environment, as well as the physical context in which people act.
This approach enables us to (1) test for the significance of lifestyles in determining CO2 emissions, (2) quantify the importance of a variety of individual socioeconomic determinants, and (3) provide a visual representation of "where" the various factors exert the greatest impact, by exploiting the spatial information contained in the lifestyle data.
Our results indicate the importance of consumer behavior and lifestyles in understanding CO2 emissions in the United Kingdom. Across lifestyle groups, CO2 emissions can vary by a factor of between 2 and 3. Our regression results provide support for the idea that sociodemographic variables are important in explaining emissions. For instance, controlling for lifestyles and other determinants, we find that emissions are increasing with income and decreasing with education. Using the spatial information, we illustrate how the lifestyle mix of households in the United Kingdom affects the geographic distribution of environmental impacts.  相似文献   
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104.
Interstrain differences in thermoregulation of rats are important in biomedical research because subtleties in thermoregulatory sensitivities may greatly affect data collected. Little is known regarding how individual rodent strains differentially utilize behavioral thermal preference to regulate core temperature (Tc). Sprague-Dawley (SD) and Fischer 344 (F344) rats are known to have differences in thermoregulation including heat tolerance and are useful models to study interstrain differences in thermoregulation. Adult male SD and F344 rats of similar body size were implanted with radiotelemetry thermoprobes (DSI) to measure Tc and MA and housed in either a longitudinal temperature gradient with an ambient temperature (Ta) range of ∼15–40 °C to measure selected Ta (STa) or control environment maintained at a Ta of 23 °C. When continuously monitored for 48 h, Tc and MA increased at night, while STa decreased, according to their normal circadian cycle in both strains. SD rats were more active than F344 rats throughout the circadian cycle (SD gradient: day=12.9±1.2 m/h, night=32.1±2.4 m/h; F344 gradient: day=4.1±0.6 m/h, night=16.8±1.8 m/h; p<0.05 interstrain and circadian effects). The STa of each strain was greater during the daytime (SD: 26.4±0.2 °C; F344: 27.8±0.3 °C) than at night (SD: 24.7±0.3 °C; F344: 25.7±0.3 °C) confirming past studies that thermopreference during the day and night is greater than standard room temperature (∼23 °C). Correlations between MA and Tc suggest that MA has a greater effect on Tc in the F344 but not the SD strain when housed in a temperature gradient. There were significant strain differences in Tc depending on whether rats were housed in a temperature gradient. That is, the control F344 rats had a lower Tc during the transition from dark to light compared to rats housed in a gradient. Tc of the SD strain was unaffected by housing in the gradient. Rats are typically housed at a standard room temperature of 23 °C. However, the results demonstrate that when given the opportunity to behaviorally thermoregulate in a temperature gradient, the F344 strain selects a warmer environment that affects the regulation of Tc. This may be important in the experimenters' choice of ambient temperatures to house and study rats and other rodents.  相似文献   
105.
Although well documented in social insects, the possibility of behavioral differentiation during collective building has been poorly studied in mammals. In this context, the mound-building mouse Mus spicilegus is an interesting model. Under natural conditions, juveniles from different litters gather vegetal material and build a sophisticated structure, the mound, under which the mice will spend winter. The first steps of this complex building process may be elicited under laboratory conditions by offering cotton balls as building material. Spatio-temporal distribution of both animals and cotton balls was automatically recorded by RFID (Radio-Frequency Identification Device) technique. Our results revealed a behavioral differentiation during a collective building task. In a group of six individuals, only two mice (called carriers) transported 80% of the building material whereas the contribution of the remaining mice was weak or even non-existent. The proportion of carriers was constant in all of the six groups studied. This behavioral differentiation was implemented immediately after the building material was made available and remained stable during the 4 days of experiment. The high contribution level of carriers did not result from resource monopolization, nor did it depend on the gender or parental origin of the mice.  相似文献   
106.
Collective foraging in group living animal populations displaying behavioral polymorphism is considered. Using mathematical modeling it is shown that symmetric, spatially homogeneous (food sources are used equally) and asymmetric, spatially inhomogeneous (only one food source is used) regimes can coexist, as a result of differential amplification of choice depending on behavioral type. The model accounts for recent experimental results on social caterpillars not only confirming this coexistence, but also showing the relationship between the two types of regime and the ratio of active to inactive individuals.  相似文献   
107.
The expected utility theory of decision making under uncertainty, a cornerstone of modern economics, assumes that humans linearly weight “utilities” for different possible outcomes by the probabilities with which these outcomes occur. Despite the theory's intuitive appeal, both from normative and from evolutionary perspectives, many experiments demonstrate systematic, though poorly understood, patterns of deviation from EU predictions. This paper offers a novel theoretical account of such patterns of deviation by demonstrating that EU violations can emerge from evolutionary selection when individual “status” affects inclusive fitness. In humans, battles for resources and social standing involve high-stakes decision making, and assortative mating ensures that status matters for fitness outcomes. The paper therefore proposes grounding the study of decision making under uncertainty in an evolutionary game-theoretic framework.  相似文献   
108.
Determining which reproductive isolating barriers arise first between geographically isolated lineages is critical to understanding allopatric speciation. We examined behavioral isolation among four recently diverged allopatric species in the orangethroat darter clade (Etheostoma: Ceasia). We also examined behavioral isolation between each Ceasia species and the sympatric rainbow darter Etheostoma caeruleum. We asked (1) is behavioral isolation present between allopatric Ceasia species, and how does this compare to behavioral isolation with E. caeruleum, (2) does male color distance and/or genetic distance predict behavioral isolation between species, and (3) what are the relative contributions of female choice, male choice, and male competition to behavioral isolation? We found that behavioral isolation, genetic differentiation, and male color pattern differentiation were present between allopatric Ceasia species. Males, but not females, discerned between conspecific and heterospecific mates. Males also directed more aggression toward conspecific rival males. The high levels of behavioral isolation among Ceasia species showed no obvious pattern with genetic distance or male color distance. However, when the E. caeruleum was included in the analysis, an association between male aggression and male color distance was apparent. We discuss the possibility that reinforcement between Ceasia and E. caeruleum is driving behavioral isolation among allopatric Ceasia species.  相似文献   
109.
A reanalysis of locomotor data from functional, energetic, mechanical and ecological perspectives reveals that limb posture has major effects on limb biomechanics, energy-saving mechanisms and the costs of locomotion. Regressions of data coded by posture (crouched vs. erect) reveal nonlinear patterns in metabolic cost, limb muscle mass, effective mechanical advantage, and stride characteristics. In small crouched animals energy savings from spring and pendular mechanisms are inconsequential and thus the metabolic cost of locomotion is driven by muscle activation costs. Stride frequency appears to be the principal functional parameter related to the decreasing cost of locomotion in crouched animals. By contrast, the shift to erect limb postures invoked a series of correlated effects on the metabolic cost of locomotion: effective mechanical advantage increases, relative muscle masses decrease, metapodial limb segments elongate dramatically (as limbs shift from digitigrade to unguligrade designs) and biological springs increase in size and effectiveness. Each of these factors leads to decreases in the metabolic cost of locomotion in erect forms resulting from real and increasing contributions of pendular savings and spring savings. Comparisons of the relative costs and ecological relevance of different gaits reveal that running is cheaper than walking in smaller animals up to the size of dogs but running is more expensive than walking in horses. Animals do not necessarily use their cheapest gaits for their predominant locomotor activity. Therefore, locomotor costs are driven more by ecological relevance than by the need to optimize locomotor economy.  相似文献   
110.
东亚飞蝗行为和形态型变的判定指标   总被引:4,自引:1,他引:4  
通过田间、室外罩笼、室内行为测试等一系列实验,研究了东亚飞蝗群居型和散居型之间的行为和形态差异。确立了东亚飞蝗不同生态型个体的形态和行为指标.结果表明,雌雄散居型蝗蝻每分钟的跳跃次数均在1.4以下,转向次数分别在1.3和1.4以下;雌雄群居型蝗蝻每分钟的跳跃次数均在1.6以上,转向次数分别在1.6和1.5以上.群居型蝗虫的跳跃次数、转向次数显著高于散居型蝗虫。所以跳跃次数、转向次数可作为东亚飞蝗行为型变判定指标.在同型不同性别的蝗虫之间行为型变指标没有显著差异.F/C值可作为4龄以上东亚飞蝗的形态型变判定指标。而E/F值可作为东亚飞蝗成虫的形态型变判定指标.两型的F/C值都随龄期的增长而增加,且同龄期雄虫F/C均大于雌虫F/C.F/C、E/F值在不同型态和同型不同性别间均存在极显著差异.因此,确定两型形态型变标准时应将雌、雄虫分开,即雌性和雄性散居型第4、5龄及成虫的F/C值分别大于2.5、2.8、3.3和2.6、2.9、3.5;雌性和雄性群居型第4、5龄及成虫的F/C值分别小于2.5、2.7、3.1和2.5、2.8、3.3.成虫的E/F值也可以作为成蝗形态型变的判断指标.  相似文献   
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