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21.
The biological roots of morality   总被引:2,自引:0,他引:2  
The question whether ethical behavior is biologically determined may refer either to thecapacity for ethics (e.i., the proclivity to judge human actions as either right or wrong), or to the moralnorms accepted by human beings for guiding their actions. My theses are: (1) that the capacity for ethics is a necessary attribute of human nature; and (2) that moral norms are products of cultural evolution, not of biological evolution.Humans exhibits ethical behavior by nature because their biological makeup determines the presence of the three necessary, and jointly sufficient, conditions for ethical behavior: (i) the ability to anticipate the consequences of one's own actions; (ii) the ability to make value judgements; and (iii) the ability to choose between alternative courses of action. Ethical behavior came about in evolution not because it is adaptive in itself, but as a necessary consequece of man's eminent intellectual abilities, which are an attribute directly promoted by natural selection.Since Darwin's time there have been evolutionists proposing that the norms of morality are derived from biological evolution. Sociobiologists represent the most recent and most subtle version of that proposal. The sociobiologists' argument is that human ethical norms are sociocultural correlates of behaviors fostered by biological evolution. I argue that such proposals are misguided and do not escape the naturalistic fallacy. The isomorphism between the behaviors promoted by natural selection and those sanctioned by moral norms exist only with respect to the consequences of the behaviors; the underlying causations are completely disparate.This article is based on a paper presented at the International Symposium onBiological Models of Human Action, Palma de Mallorca, Spain, 16–18 December 1985.  相似文献   
22.
This is the ninth installment of our annual review of research involving the endogenous opiate peptides. It is restricted to the non-analgesic and behavioral studies of the opiate peptides published in 1986. The specific topics this year include stress; tolerance and dependence; eating; drinking; gastrointestinal, renal, and hepatic processes; mental illness; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; activity; sex, pregnancy, and development; and some other behaviors.  相似文献   
23.
Reuyen Dukas 《Oecologia》1987,74(2):256-263
Summary The behavior of Apis mellifera and two species of solitary bees which forage in the flowers of monoecious Ecballium elaterium (L.) A. Rich (Cucurbitaceae) were compared. The female flowers of E. elaterium resemble male flowers visually but are nectarless, and their number is relatively smaller. Apis mellifera was found to discriminate between the two genders and to pay relatively fewer visits to female flowers (mean of 30% relative to male flowers) from the beginning of their activity in the morning. The time spent by honeybees in female flowers is very short compared to that spent in male flowers. It is surmised that the bees remember the differences between the flowers where they foraged on the previous days. In contrast, the two species of solitary bees Lasioglossum politum (Morawitz) (Halictidae) and Ceratina mandibularis Fiese (Anthophoridae) visit the female flowers with nearly equal frequencies at the beginning of each foraging day and stay longer in these flowers. Over the day there is a decline in the relative frequency of visits to female flowers and also in the mean time spent in them. The study shows that bees can collect rewards at high efficiency from the flowers of Ecballium elaterium because of their partial discrimination ability and the scarcity of the mimic flowers. It is suggested that the memory pattern of some solitary bees may be different from that of Apis mellifera. It seems that the limited memory and discrimination ability of bees can lead to a high frequency of visits to the mimic flowers during a long flowering season.  相似文献   
24.
We examined the intra-tree foraging behavior of individually-released, wild-population Mediterranean fruit flies (medflies), Ceratitis capitata (Wiedemann), on field-caged host trees bearing each of three different densities (0, 3, or 12 per tree) of non-infested host fruit (kumquat) or each of two levels of fruit quality (12 non-infested fruit or 12 fruit infested with eggs and covered with host marking pheromone). With increasing density of non-infested fruit, medflies tended to remain longer in trees, visit more fruit before leaving, oviposit more often, accept a proportionately smaller number of fruit visited, and emigrate sooner after the last egg was laid (i.e. have a shorter Giving-Up-Time). Medflies spent much less time, oviposited much less often, and exhibited a longer Giving-Up-Time on trees harboring pheromone-marked fruit than non-infested fruit. Variation in temperature within the range at which experiments were conducted (25–36°C) had little detectable influence on foraging behavior. We compare our findings with published findings on the intra-tree foraging behavior of another tephritid fly, Rhagoletis pomonella (Walsh), and with current foraging behavior theory. We discuss implications of our findings with respect to medfly management strategies, particularly fruit stripping in eradication programs and use of synthetic marking pheromone for control.
Résumé Nous avons étudié le comportement de prospection dans un arbre, de femelles d'une population sauvage de C. capitata, libérées individuellement à l'intérieur de cages contenant des Eriobotrya japonica (kumquat), portant chacun 3 densités différentes de fruits no contaminés (0, 3, 12 par arbre) et chacun 2 niveaux de qualité de fruits: 12 fruits non infestés ou 12 fruits contaminés par des oeufs et recouverts de phéromone de marquage de l'hôte. C. capitata avait terndance à rester plus longtemps dans les arbres, à visiter plus de fruits avant le quitter, à pondre plus souvent, à accepter proportionnellement un nombre plus réduit de fruits déjà visités, à émigrer plus tôt après la ponte du dernier oeuf (c'est-à-dire à présenter un temps d'abandon plus bref), quand la densité des fruits non contaminés augmentait. C. capitata a dépensé beaucoup moins de temps, pondu beaucoup moins souvent, et présenté un temps d'abandon plus long sur les arbres portant des fruits marqués par la phéromone que sur ceux ayant des fruits non contaminés. Les variations de température dans la gamme de cells où les observations ont eu lieu (23–36°C) n'ont eu qu'une faible influence décelable sur le comportement de prospection. Nous avons comparé nos résultats avec ceux publiés sur la prospection à l'intérieur de l'arbre par une autre téphritide (Rhagoletis pomonella) et avec la théorie dominante sur le comportement de prospection. Nous discutons les conséquences de nos résultats sur les stratégies de lutte contre C. capitata, en particulier l'élimination des fruits dans les plans d'erradication et l'utilisation de phéromone synthétique de marquage.
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25.
The question of whether the appearance of a novel deleterious chemical in a preferred host plant could alter the relative degree of preference by a polyphagous insect during its lifetime was considered. The behavioral preference of fall armyworm, Spodoptera frugiperda (J. E. Smith), for corn (Zea mays L.) over red kidney bean Phaseolus spp. was quantified in a two-way choice test, and followed by a no-choice test in which the same larvae were fed either treated or untreated corn. Each treatment consisted of one of 15 compounds, including 13 naturally occurring allelochemicals and two synthetic insecticides. None of the test chemicals had any inherently deterrent effect at the rates tested. Deleterious effects on the larvae during exposure included reduced growth, reduced size, irritancy, and in some cases death. After this exposure the two way choice test was repeated. All test compounds failed to elicit a change in relative preference during the final two-way choice test. However, larvae exposed to gossypol and chrysanthemum monocarboxylic acid ester fed less than expected during the latter stages of no-choice conditions. The degree of aversion learning by each larva was related to the degree of prior sickness it had experienced.
Résumé Nous avons examiné si l'introduction d'une substance chimique nocive dans la plante-hôte préférée pouvait modifier la hiérarchie des choix durant le reste de la vie d'un insecte phytophage. Le comportement de préférence de Spodoptera frugiperda pour le maïs (Zea mays) vis à vis des Phaseolus, a été quantifié dans un dispositif à choix binaire, ont suivi des expériences au cours desquelles les chenilles devaient s'alimenter, soit sur maïs sain, soit sur maïs traité. Chaque essai concernait un composé chimique (15 au total), 13 étant des substances allélochimiques naturelles, 2 des insecticides de synthèse. Aux concentrations étudiées, aucun des produits n'a eu d'effet dissuasif. Les effets nocifs pendant l'exposition sur les chenilles comprenaient une croissance et une taille réduites, une irritation et, dans quelques cas, la mort. Aucune des expériences de choix binaire, avec des chenilles ayant subi cette exposition, n'a modifié les préférences. Cependant les chenilles, qui avaient été exposées au gossypol ou à l'acide monocarboxylique éthyl ester de chrysanthemum, ont consommé moins pendant les stades ultérieurs que ce que l'on pouvait attendre en absence de choix. Le degré d'aversion acquis par chaque chenille dépendait de l'importance des maux qu'elle avait subis précédemment.
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26.
Electroantennogram (EAG) measurement of male Cydia caryana moth antennal olfactory response to monounsaturated 12 and 14 carbon alcohols and acetates indicated that the (E)-8-, (E)-10- conjugated double bond system of a dodecadien-1-ol acetate is a critical chemical structural component of the C. caryana sex pheromone. Additionally, EAG measurements implicated (E)-8-dodecen-1-ol acetate, (Z)-8-dodecen-1-ol acetate, (Z)-9-dodecen-1-ol acetate and (Z)-12-tetradecen-1-ol as potential minor pheromonal components. An EAG dosage-response study suggested that there were at least two heterologous populations of pheromone acceptors. Behavioral analysis of male moth response in a flight tunnel to compounds which evoked the stronger EAG responses suggested that (E,E)-8,10-dodecadien-1-ol acetate and (Z)-9-dodecen-1-ol acetate resemble or are C. caryana sex pheromonal components, while (Z)-8-dodecen-1-ol acetate and (E)-10-dodecen-1-ol acetate are either parapheromones or are minor pheromone components. Behavioral significance of (Z)-12-tetradecen-1-ol was difficult to interpret in the flight tunnel.
Résumé Les réponses olfactives antennaires de Cydia caryana, mesurées par électroantennogrammes (EAG), aux alcools et acétates à carbones monounsaturés en positions 12 et 14, ont montré que le système conjugué de double liaison, (E)-8-, (E)-10- du dodecadien-1-ol acétate constitue un composé chimique strutural critique de la phéromone sexuelle de C. caryana.De plus, les acétates: (E)-8-dodecen-1-ol,(Z)-8-dodecen-1-ol,(Z)-9-dodecen-1-ol, et le (Z)-12-tetradecen-1-ol, se sont révélés en AEG comme des composés secondaires de la phéromone. L'étude par AEG de la relation dose-réponse a conduit à l'hypothèse de deux catégories de populations de récepteurs de phéromones. L'analyse comportementale des résponses des papillons mâles dans le tunnel de vol aux composés qui ont provoqués les plus forts AEG, on fait estimer que les acétates (E,E)-8,10-dodécadien-1-ol et (Z)-9-dodecen-1-ol ressemblent (ou sont) les constituants de la phéromone sexuelle de C. caryana; tandis que les (Z)-8-dodecen-1-ol et (E)-10-dodecen-1-ol sont, soit des paraphéromones, soit des constituants mineurs de la phéromone.La signification biologique du (Z)-12-tétradécen-1-ol a été difficile à interprêter avec les expériences en tunnel de vol.
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27.
First and fourth instars of three birch aphid species were exposed to first and fourth instars of Adalia bipunctata (L.), the most common aphid predator on silver birch, Betula pendula Roth, in northern California. Defensive behavior differed by aphid species. Euceraphis betulae (Koch) (Eb), the most successful escapee, was highly mobile and frequently walked away from coccinellid larvae. Betulaphis brevipilosa Börner (Bb), a flat, sessile species, was the least successful aphid at actively escaping from A. bipunctata larvae, but could passively escape detection when coccinellid larvae walked over nymphs and did not perceive them. Active escape behavior was much safer for aphids than passive avoidance of detection. Both instars of Eb and fourth instars of Callipterinella calliptera (Hartig) (Cc) escaped from coccinellid larvae more frequently when approached from the front, apparently using vision for pre-contact detection of A. bipunctata. These aphids avoided physical contact with larger predators more often than with smaller predators. Level of predation by A. bipunctata on these three aphid species is dependent upon types of aphid defense.
Résumé Des larves de premier et troisième stades de 3 espèces de pucerons du bouleau: Betulaphis brevipilosa, Callipterinella calliptera et Euceraphis betulae ont été exposées aux attaques des larves du premier et du quatrième stades d'Adalia bipunctata, prédateur le plus fréquent de pucerons sur Betula pendula en Californie du Nord. Le comportement défensif dépend beaucoup de l'espèce de puceron. E. betulae, qui s'échappe avec le plus de succès, est très mobile et s'écarte fréquemment des larves agressives de coccinelles. B. brevipilosa, espèce plate, sessile, a le moins de succès dans la protection active contre les attaques des larves de A. bipunctata, mais elle peut échapper passivement à la détection des larves de coccinelles qui ne peuvent pas les discerner lorsqu'elles circulent parmi les larves de pucerons. E. betulae (aux deux stades) et C. calliptera (au quatrième) échappent le plus aux larves de coccinelles qui attaquent de front, ce qui laisse supposer que la vision permet de détecter A. bipunctata avant le contact. Le succès des larves de coccinelles varie selon les stades du puceron et de la coccinelle. Les possibilités d'obtention de niveaux de prédation élevés de ces 3 pucerons par A. bipunctata dépend du type de protection du puceron.
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28.
Summary We studied the nesting success of Evening Grosbeaks (Coccothraustes vespertinus) inhabiting two areas of the Front Range of the Rocky Mountains of Colorado from 1983–1987. Sixty-four nests were followed during building, incubating, brooding, and fledging; 54.7% were successful (young fledged). The largest number of nests failed during incubation. Nests started later were more successful than nests begun earlier in the season. Failure was most likely due to severe weather, abandonment during building, or predation. Specific habitat characteristics of grosbeak nesting sites and where nests were placed in trees were consistently associated with nesting success. Successful nests, when compared with nests that failed, were: (1) built in more open areas characterized by dispersed vegetation and a higher minimum canopy, (2) oriented in more southerly directions, (3) built closer to the main trunk of the nest tree, and (4) built in larger trees. Current ideas about whether or not birds actually select nest-sites are briefly discussed. We conclude that some grosbeaks optimally select nest sites where the likelihood of producing fledglings is higher than in other areas.  相似文献   
29.
Summary Females of the sunflower moth, Homoeosoma electellum held in the presence of pollen, or an ethanolic pollen extract, from the sunflower Helianthus annuus initiated calling behavior at a significantly younger age following emergence than those provided sucrose only. Furthermore, females with pollen subsequently spent more time calling, and had an increased rate of egg maturation, than those held without pollen. These effects were attributed to a kairomone as females held in the presence of, but denied direct access to, pollen behaved in the same manner as those in contact with pollen. The importance of this life history strategy for the exploitation of temporarily available resources, essential to the survival of neonate larvae, and on the dispersal of adults, is discussed.  相似文献   
30.
When the individual Japanese macaques of the Koshima troop feed on natural food, they usually feed alone. In situations where animals usually feed without other animals, there is a possibility that subordinate animals may avoid feeding sites at which dominant animals are feeding. This paper examines whether social relationships such as kinship or dominance exert any influence on an animal's choice of feeding sites, by analyzing episodes in which an animal approached and climbed into a tree where other animals were. As a result, it was found that social relationships did not influence whether an animal climbed into a tree where other animals were feeding, and that no particular age-sex pair co-fed. Agonistic interactions frequently occurred when the inter-individual distance was less than 1 m. From these findings, the feeding sites were divided into two spaces: (1) a tolerance feeding space, and (2) an intolerance feeding space. It is presumed that animals can feed without entering others' intolerance feeding spaces when food is abundant, as it was in the present study period. Thus social relationships do not influence an animal's choice of feeding sites in such a situation.  相似文献   
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