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Kathryn Paxton George 《Journal of Agricultural and Environmental Ethics》1992,5(2):217-233
In response to Evelyn Pluhar'sWho Can Be Morally Obligated to Be a Vegetarian? in this journal issue, the author has read all of Pluhar's citations for the accuracy of her claims and had these read by an independent nutritionist. Detailed analysis of Pluhar's argument shows that she attempts to make her case by consistent misappropriation of the findings and conclusions of the studies she cites. Pluhar makes sweeping generalizations from scanty data, ignores causal explanations given by scientists, equates hypothesis with fact, draws false cause conclusions from studies, and in one case claims a conclusion opposite of what the scientist published. Such poor reasoning cannot be the basis of an argument for moral vegetarianism. A broader search of the literature and attention to reviews and textbooks in nutrition shows that each of Pluhar's claims is suspect or incorrect. Pluhar has not undermined my central claims: even if animals have certain rights and well-planned vegetarian diets are safe in complex industrialized societies, these diets cannot be so regarded if the presuppositions of high levels of wealth, education, and medical care do not exist; and, women, children, the aged and some ill persons are at greater risk on restrictive vegan diets. Thus, any duty of moral vegetarianism is not categorical but provisional in nature. 相似文献
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Hiroe Yasui Toshiharu Akino Midori Fukaya Sadao Wakamura Hiroshi Ono 《Chemoecology》2008,18(4):233-242
Summary. We conducted a series of experiments with the white-spotted longicorn beetle Anoplophora malasiaca (Thomson), and its host plant, Citrus unshiu, to examine the origin of the sesquiterpene hydrocarbons (SHCs; including β-elemene, β-caryophyllene, α-humulene, α-farnesene,
and several unidentified compounds) that are contained in the elytra of the beetles and act as an attractant. In the laboratory,
mechanically wounded citrus branches, as well as those fed upon by A. malasiaca, attracted males more frequently than intact branches. Solid phase microextraction (SPME) and subsequent analyses by gas
chromatography (GC) analyses detected measurable SHCs from the air around both mechanically wounded and beetle-infested branches,
as well as trace amounts from intact branches. The SHCs were also detected for a certain time from beetles that had fed on
the citrus branches, but the amounts decreased rapidly after they were removed from the host. This decrease generally corresponded
with a reduction of attractiveness of the beetles in a behavioural assay. Isolated females acquired the SHCs after exposure
to, but not upon contact with, other females that had fed on C. unshiu branches. We hypothesize that the citrus SHCs are adsorbed in, retained on, and released from the wax layer of the beetle
elytra. Since these compounds are released from branches when beetles feed, they may indirectly signal the presence of beetles
to others in the field. The high response rate to SHCs by males is likely representing mate searching behavior. The SHCs act
as kairomones with a releaser effect in the communication system of A. malasiaca.
Hiroe Yasui, Toshiharu Akino, Midori Fukaya: These authors contributed equally to this article. 相似文献
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To aid in the management and conservation of Southwestern Willow Flycatcher (Empidonax traillii extimus, hereafter “Flycatcher”), we developed numerous models of flycatcher breeding habitat at Roosevelt Lake, AZ. For model development and testing, we compiled 10 years of flycatcher territory data that were obtained from intensive fieldwork between 1996 and 2005. We identified riparian vegetation annually in the project area from Landsat Thematic Mapper images, and extracted floodplain features from a digital elevation model. We created a novel class of temporal (i.e., multiyear) variables by characterizing the stability and variability in breeding habitat over a 6-year time interval. We used logistic regression to determine associations between environmental variables and flycatcher territory occurrence, and to test specific hypotheses. We mapped the probability of territory occurrence with a GIS and determined model accuracies with a classification table and a 10-year population database. Environmental features that were associated with breeding flycatchers included floodplain size, proximity to water, and the density, heterogeneity, age and stability of riparian vegetation. Our best model explained 79% of the variability in the flycatcher breeding population at Roosevelt Lake. The majority of predicted flycatcher habitat formed between 1996 and 2004 on an exposed lakebed ~3 years after water levels receded during a prolonged drought. A high correlation between annual reservoir levels and predicted breeding habitat (r = ?0.82) indicates that we can create and manage habitat for conservation purposes. Our predictive models quantify and assess the relative quality of flycatcher breeding habitat remotely, and can be used to evaluate the effectiveness of habitat restoration activities. Numerous techniques we developed can be used to characterize riparian vegetation and patch dynamics directly off of satellite imagery, thereby increasing its utility for conservation purposes. 相似文献
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For primitively eusocial insects in which a single foundress establishes a nest at the start of the colony cycle, the solitary provisioning phase before first worker emergence represents a risky period when other, nestless foundresses may attempt to usurp the nest. In the primitively eusocial sweat bee Lasioglossum malachurum (Hymenoptera, Halictidae), spring foundresses compete for nests which are dug into hard soil. Nest-searching foundresses (‘floaters’) frequently inspected nests during this solitary phase and thereby exerted a usurpation pressure on resident queens. Usurpation has been hypothesised to increase across the solitary provisioning phase and favour closure of nests at an aggregation, marking the termination of the solitary provisioning phase by foundresses, before worker emergence. However, our experimental and observational data suggest that usurpation pressure may remain constant or even decrease across the solitary provisioning phase and therefore cannot explain nest closure before first worker emergence. Levels of aggression during encounters between residents and floaters were surprisingly low (9% of encounters across 2 years), and the outcome of confrontations was in favour of residents (resident maintains residency in 94% of encounters across 2 years). Residents were significantly larger than floaters. However, the relationship between queen size and offspring production, though positive, was not statistically significant. Size therefore seems to confer a considerable advantage to a queen during the solitary provisioning phase in terms of nest residency, but its importance in terms of worker production appears marginal. Factors other than intraspecific usurpation need to be invoked to explain the break in provisioning activity of a foundress before first worker emergence. 相似文献
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Gustavo R. Makert Robert J. Paxton Klaus Hartfelder 《Behavioral ecology and sociobiology》2006,60(6):815-825
A honeybee queen normally mates with 10–20 drones, and reproductive conflicts may arise among a colony’s different worker patrilines, especially after a colony has lost its single queen and the workers commence egg laying. In this study, we employed microsatellite markers to study aspects of worker reproductive competition in two queenless Africanized honeybee colonies. First, we determined whether there was a bias among worker patrilines in their maternity of drones and, second, we asked whether this bias could be attributed to differences in the degree of ovary activation of workers. Third, we relate these behavioral and physiological factors to ontogenetic differences between workers with respect to ovariole number. Workers from each of three (colony A) and one (colony B) patrilineal genotypes represented less than 6% of the worker population, yet each produced at least 13% of the drones in a colony, and collectively they produced 73% of the drones. Workers representing these genotypes also had more developed follicles and a greater number of ovarioles per ovary. Across all workers, ovariole development and number were closely correlated. This suggests a strong effect of worker genotype on the development of the ovary already in the postembryonic stages and sets a precedent to adult fertility, so that “workers are not born equal”. We hypothesize a frequency-dependent or “rare patriline” advantage to queenless workers over the parentage of males and discuss the maintenance of genetic variance in the reproductive capacity of workers.Electronic supplementary material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
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Halihan T Paxton S Graham I Fenstemaker T Riley M 《Journal of environmental monitoring : JEM》2005,7(4):283-287
Present understanding of the earth's subsurface is most often derived from samples at discrete points (wells) and interpolations or models that interpret the space between these points. Electrical resistivity imaging techniques have produced an improved capability to map contaminants (especially NAPLs--NonAqueous Phase Liquids) away from traditional wells using actual field data. Electrical resistivity image data, confirmed by drilling, have demonstrated that LNAPL (Light NAPL--less dense than water, such as gasoline) contaminants exist outside of a delineated and remediated area in Golden, Oklahoma. The data also demonstrate that LNAPL exists between monitoring and remediation wells which indicate low contaminant levels when sampled. Additionally, the electrical images provided the drilling location with the highest concentration of hydrocarbon ever found on the site, even after two phases of remediation work had been performed, although the sampling protocols varied. The results indicate that current methods of post-remediation site characterization are inadequate for complete site characterization. 相似文献
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In her recent Counter-Reply to my views, Evelyn Pluhar defends her use of literature on nutrition and restates her argument for moral vegetarianism. In his Vegan Ideal article, Gary Varner claims that the nutrition literature does not show sufficient differences among women, men, and children to warrant concern about discrimination. In this response I show how Professor Pluhar continues to draw fallacious inferences: she begs the question on equality, avoids the main issue in my ethical arguments, argues from irrelevancies, misquotes her sources, equivocates on context, confuses safety with morality, appeals to fear, confuses correlation with cause, fails to evaluate scientific studies, draws hasty conclusions from insufficient data, ignores a large amount of data which would call her views into question, does not follow good scientific or moral argumentation, objectionably exceeds the limits of her expertise, and resorts to scapegoating. I also argue that Professor Varner fails to make his case because he offers virtually no evidence from scientific studies on nutrition, relies on outdated and fallacious sources, makes unsupported claims, ignores evidence that would contravene his claims, draws hasty conclusions based on weakly supported hypotheses rather than facts, employs a double standard, appeals to ignorance, does not evaluate arguments from his sources, and makes anad hominem attack on a respected nutritionist when his focus should be on evaluating the evidence and arguments from the scientific studies themselves. Neither Varner nor Pluhar have responded sufficiently to the real issue in my arguments, that of discrimination and bias in the vegan ideal. 相似文献
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