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351.
352.
David Hershenov 《Bioethics》2018,32(7):430-436
Material property has traditionally been conceived of as separable from its owner and thus alienable in an exchange. So it seems that you could sell your watch or even your kidney because it can be removed from your wrist or abdomen and transferred to another. However, if we are each identical to a living human animal, self‐ownership is impossible for self‐separation is impossible. We thus cannot sell our parts if we don't own the whole that they compose. It would be incoherent to own all of your body's parts but not the whole body; and it would be arbitrary to own some but not all of your removable parts. These metaphysical obstacles to organ sales do not apply to the selling of the organs of the deceased. The human being goes out of existence at death and is not identical to the body's remains. Any objections to selling the organs of the deceased must instead be due to dignity rather than metaphysical or conceptual considerations. But the remains lack the intrinsic dignity of the human being, instead possessing, at best, relational dignity. Relational dignity would not provide sufficient reason to prohibit life‐saving sales.  相似文献   
353.
Intraspecific territorial interactions are common for a largevariety of wildlife species. This often results in high-qualityhabitat being occupied by dominant individuals, with subordinatesrelegated to lower quality habitat. The role that these territorialinteractions play in influencing the redistribution of animalsthat have been evicted from their native home ranges remainsunclear. My goals were to determine (1) how the density of conspecificsin the new habitats impacts resettlement patterns and (2) towhat extent prior dominance status is maintained when an animalis forced to relocate. I relocated white-footed mice (Peromyscusleucopus) from high-quality, oak-dominated hardwood and lowerquality, white pine forests to novel sites and released themalong the ecotone of these two habitat types. I relocated micefirst in the presence and then in the absence of a natural densityof resident mice. Habitat selection and resource acquisitionof relocated mice were assessed via mark-recapture livetrappingand passive integrated transponder tagging. Relocated mice selectedhigh-quality habitat significantly more often when residentmice were absent, illustrating the importance of territorialinteractions for determining resettlement patterns of relocatedindividuals. Data on resource acquisition also reflected thecompetitive influence of resident mice—relocated micewere significantly more successful accessing food resourcesin the treatment without residents. The habitat of origin didnot significantly impact habitat selection or resource acquisition,indicating that all relocated individuals were at a disadvantagecompared to residents.  相似文献   
354.
《Current biology : CB》2021,31(18):4120-4126.e4
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355.
Scent-marking is an important form of communication for solitary species, as the information remains for the receiver after the sender has left the area. Individuals of different demographic or dominance classes (ranks) need to provide different information to conspecifics. Therefore, the use of scent-marking sites is of particular value for solitary species, but their functional role may vary between demographic classes. Using camera traps, we video-recorded the behaviour of cheetahs at scent-marking sites, assessing how individuals of different sex and social rank use the sites for different roles. We tested hypotheses that these sites are for territorial marking, reproductive signalling and information gathering. We found that females visit the sites infrequently, apparently to signal oestrous events, while males visit the sites frequently for territorial marking and information gathering. Among males, dominant individuals scent-marked the most and reacted to female visitation by vocalizing. In contrast, subordinate males, although also visiting the sites, were not recorded scent-marking nor vocalizing. These differences in the functional use of scent-marking sites among sex and social rank support the hypotheses that cheetah s use these scent-marking sites for both territorial and reproductive signalling, as well as to gather information.  相似文献   
356.
During the breeding season, great tits show aggression to protect their nest from intra‐ and interspecific intruders. Aggression is a labile trait that can be plastically expressed as a result of individual differences (e.g., personality), seasonal gradients in the costs and benefits of aggression, or other environmental components (e.g., number of competitors). Competitors may try to take over great tit nests, because the number of suitable nesting sites is limited, and great tits may guard high quality territories. Taking over a great tit nest may be especially fruitful in early phenological stages (egg laying) when great tits frequent their nests less often. However, great tits may compensate for this vulnerability by being more aggressive toward intruders during early nesting stages, a pattern that has already been established in an intraspecific context. Previous studies have shown that interspecific intruders were most likely to die from great tit aggression during great tit egg laying, suggesting great tits may also be more aggressive during this phase in an interspecific context. Here, I tested this hypothesis with simulated territorial intrusions in great tit territories using taxidermized blue tits Cyanistes caeruleus (hereafter called blue tit models). Great tit aggression (number of calls and approach distance toward blue tit model) was assayed during egg laying, incubation, and chick rearing in the breeding season of 2014. Although sample size was low due to a high fraction of non‐responders (n = 44 out of 89 assays across 26 out of 35 individuals), I found that great tits showed a seasonal decline in aggressiveness, which is congruent with intraspecific results on this study species. I discuss my findings in the context of differential adjustment to climate change between interspecific competitors.  相似文献   
357.
ABSTRACT Carotenoid‐based coloration of skin and plumage has been found to be correlated with individual quality in many species of birds during the breeding season. However, less is known about the possible role of these signals during the nonbreeding season, particularly among nonpasserines that defend winter territories. American Kestrels (Falco sparverius) are sexually dimorphic raptors that defend winter territories and possess carotenoid‐based morphological features known to be correlated with individual quality. Much is known about winter territory use and habitat segregation by male and female kestrels, but possible relationships among morphological features, individual quality, and habitat quality have not been examined. Our objective was to examine possible relationships between morphology, territory quality, and skin color of American Kestrels. Male kestrels had brighter skin than females, and the skin color of male kestrels was positively correlated with size (wing chord and tail length) and territorial quality (hunting territories with less canopy and more grass cover). No such relationships were found for female kestrels. Skin color appears to be an honest indicator of quality for male American Kestrels and may serve both intersexual (territory acquisition) and intersexual (mate choice) functions during the breeding and nonbreeding seasons.  相似文献   
358.
359.
Quantitative studies on nesting habitat selection are important to understand and predict the resource requirements for breeding habitat. In this study, we analysed nest-site (cliff) and territory selection patterns of the Bearded Vulture in the Annapurna Range of the Himalayas (Nepal). Our study area represents high-elevation mountain range systems, where information on nest selection is lacking, despite having the largest remaining populations of Bearded Vultures in the world. Our models indicated selection patterns at both nest and territory spatial scales that are consistent with previous studies at lower altitudes (Pyrenees, the Caucasus), such as a preference for landscape patches with greater food availability. However, our models also indicated selection patterns that are probably a response to the higher altitudes and sheer reliefs of the Annapurna massif, such as avoidance of the steepest slopes and selection of cliffs facing south and west for nest-sites. We did not detect an impact of human activities on the distribution of nests or territories. However, the Annapurna massif is experiencing development of infrastructures (e.g. road construction). Further research efforts will be needed to monitor human impacts on Bearded Vulture populations in the Annapurna Range, as this is a global stronghold for this species.  相似文献   
360.
Males of the Mediterranean fruit fly, Ceratitis capitata (medfly), defend individual leaves of host and non-host trees as mating territories and attract females via production of a sex pheromone (a behavior termed ‘calling’). Males tend to aggregate within the tree canopy, and the present study examined the influence of (1) location and (2) resources on female visitation to male aggregations. Males were placed in screen-covered containers, which were suspended on field-caged trees at two locations selected to differ in only one of the following parameters: height above ground (low versus high), leaf density (sparse versus dense), distance to main trunk (canopy edge versus center), proximity to a food source (bird feces absent or present), and proximity to a host fruit (oranges absent or present). Females were released, and we periodically recorded the number of calling males in each of the test aggregations as well as the number of females sighted within 15 cm of each male aggregation. Male calling did not differ between treatments in any of the experiments. However, females were more frequently sighted near males calling (1) in dense foliage, (2) near the central trunk, (3) near bird feces, and (4) near oranges. In an additional experiment, we compared male settlement (in the absence of females) on leaves in the same sites used previously to determine the degree of congruence between the sexes in microhabitat use. Aside from the lack of center-edge effect, males displayed the same settlement patterns as females. In a final experiment, we found no effect of male calling on the distribution of other males: released males were sighted with equal frequency near cups containing mature, calling males and cups containing immature, non-calling males. Medfly lek behavior is discussed in light of these findings.  相似文献   
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