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1.
In the report "Selection of social partners as a function of peer contact during rearing" by C. L. Pratt and G. P. Sackett (3 Mar., p. 1133), the third sentence of the first paragraph should read as follows: "Monkeys reared in isolation tend to withdraw from other animals and huddle by themselves in social situations. If such animals prefer each other over more normal monkeys, they may not be effectively exposed to the stimuli which lead to some degree of social adjustment."  相似文献   

2.
Newborn monkeys reared in darkness for 16 months, except for daily 1-hour periods of exposure to unpatterned light, were allowed to press a lever to obtain unpatterned light. The animals showed apparently insatiable responding, at rates that were extremely high as compared with rates for normally reared control animals.  相似文献   

3.
In male swordtails ((Xiphophorus nigrensis)) there are three size classes that derive from allelic variation at the pituitary locus on the Y chromosome. Progeny analysis and preference tests suggest that females prefer to mate with larger males. In the closely related X. pygmaeus, there is no allelic variation at this locus; this species consists of males similar in size only to smaller X. nigrensis males. In addition to being smaller than most X. nigrensis males, these X.pygmaeus males also lack both the swordtail and a major component of the courtship display common in most X. nigrensis males. Usually, female X. pygmaeus prefer to mate with heterospecific males rather than conspecifics, regardless of body size and the presence of a swordtail. However, the smallest X. nigrensis males lack the same courtship component as do the X. pygmaeus males, and in this comparison female X. pygmaeus show no preference. Although sexual selection, through its action on divergence of courtship displays, has been implicated as a factor leading to speciation, in this case sexual selection could lead to the congealing of gene pools between heterospecifics.  相似文献   

4.
Thirsty rodents will persistently lick a stream of dry air pumped through a standard drinking tube. This air-licking is attenuated by experimental manipulations which reduce the evaporative cooling of the tongue and mouth produced by the airstream. This suggests that such cooling is itself an effective reward for thirstry rodents. We tested this hypothesis by presenting thirsty rodents with a piece of cold, dry metal. Different species spent from 9 to 40 percent of their session time licking the cold metal. When deprived of water hamsters reared from birth without access to drinking water licked cold metal in preference to metal maintained at room or body temperature. This preference was approximately equal to that of littermates reared normally. We conclude that tongue cooling is a primary reward for thirsty rodents.  相似文献   

5.
Rats were provided with opportunity to turn reinforcing hypothalamic stimulation on and off by traversing back and forth across a chamber. When provided with edible and inedible objects, all animals that self-stimulated carried them from the stimulation to the nonstimulation side. Neither food deprivation nor a history of stimulus-bound eating produced a preference for the edible objects. Equivalent stimulation provided without regard to the animals' location in the chamber did not elicit object-carrying. Results are interpreted in terms of the natural conditions which normally elicit this species-specific unit of behavior. Implications for understanding other behavior patterns elicited by hypothalamic stimulation are suggested.  相似文献   

6.
Consumers are becoming increasingly interested in how their food is produced. Many studies have focused on consumers’ preferences and willingness-to-pay for specific production-related claims (labels) on food products. However, few studies have asked consumers to rank the importance of different production claims. In this study, we use a best-worst scaling approach to have consumers rank the importance of seven common production claims used on food products. Rankings are obtained across four product types: beef, milk, chicken, and eggs. Results of the study show that consumers often prefer specific components of more encompassing claims (e.g., animals were not treated with growth hormones, no GMOs used in production) as opposed to the broader, more encompassing claim itself (such as product is certified organic). The majority of preference shares were captured by the top three claims, though the order of these preferences appears to vary for meat and non-meat animals.  相似文献   

7.
Three rhesus monkeys which had been isolated from social contact during their first year of life persistently overate and overdrank during adulthood. These monkeys ingested approximately twice as much fluid and food as the control animals reared normally.  相似文献   

8.
[目的]探讨3种粘虫各龄幼虫对4种寄主植物的取食选择行为,为粘虫的预测预报及防治提供理论依据.[方法]采用叶碟改进法分别测试3种粘虫(东方粘虫、劳氏粘虫和淡脉粘虫)在4种寄主植物(玉米、水稻、甘蔗和稗草)上的取食选择性,分别于接虫后6和24 h记录幼虫对各植物的选择数量.[结果]3种粘虫各龄幼虫在接虫后6和24 h时对4种寄主植物的取食选择率均有变化.在24 h时,东方粘虫各龄幼虫对玉米的选择率均显著高于其他3种寄主植物(P<0.05,下同),其中1龄和2龄幼虫对玉米的选择率分别高达82%和89%;劳氏粘虫1~6龄幼虫偏好取食玉米,其中1龄、2龄和3龄幼虫对玉米的选择率均超过50%,分别为78%、70%和55%,显著高于对其他3种寄主植物的选择率;淡脉粘虫1~6龄幼虫均偏好取食水稻,其中2~4龄幼虫对玉米和水稻的选择率差异不显著(P>0.05).[结论]3种粘虫各龄幼虫对4种寄主植物的取食选择存在差异,3种粘虫对玉米和水稻的取食选择性强,对甘蔗和稗草的取食选择性较弱;东方粘虫和劳氏粘虫低龄幼虫喜食玉米,淡脉粘虫低龄幼虫嗜食水稻和玉米,高龄幼虫的取食选择性不如低龄幼虫明显.  相似文献   

9.
刘松 《安徽农业科学》2014,(13):3939-3943
通过场景可视化技术,利用图像处理软件模拟在同一背景下不同景观空间特征梯度和不同农业生产模式的场景图片,并通过参与式评估技术,获取新疆阿克苏地区乌什县八乡一镇180名受访者的偏好意愿。通过对调查结果的统计、分析,评价不同利益相关者对村镇体系景观发展趋势的偏好。结果显示:一般来看,绝大多数受访者不愿意选择多样性较强的景观;多数受访者更喜欢破碎度较弱的景观;对于景观聚集度的偏好程度在各个利益群体中的差异都不甚明显;受访者通过场景图片更加偏好菜地景观,而通过语言和理性思考后则更倾向于选择农田景观。受访者因年龄、自身文化程度、收入、农业生产所占收入比例等因素会偏好不同的景观。研究表明,运用场景可视化技术将不同利益相关者对村镇体系景观空间格局的偏好融入景观评价中,是一种比较实际、可行的方法。  相似文献   

10.
大熊猫在原始林和次生林中生境利用的比较研究   总被引:16,自引:1,他引:16  
在四川省宝兴县大熊猫栖息地中调查了 12种生态因子的 5 8种生境类型 ,利用Forageratio指数对大熊猫在原始林和次生林中的生境选择进行了比较研究 .在原始林 2 0 82个样方中发现有大熊猫痕迹样方 4 31个 ,有大熊猫痕迹样方数占调查样方数的 2 0 7% ;在 15 82个次生林样方中有大熊猫痕迹样方 15 2个 ,有大熊猫痕迹样方数占调查样方数的 9 6 % .研究结果表明 :①原始林中大熊猫回避大于坡度 4 0°的生境类型 ,而在次生林生境中对坡度没有表现明显的偏好 .②坡向和乔木郁闭度对大熊猫的生境选择没有明显影响 .③原始林和次生林中的大熊猫都偏好针阔混交林 ,但在次生林中还把选择范围扩大到针叶林和阔叶林 .④原始林中大熊猫偏好乔木胸径 30~ 5 0cm的生境 ,次生林中降至 2 0cm以上 .⑤大熊猫在原始林中回避竹类植物盖度低于 5 0 %的生境 ,在次生林则随机选择这类生境 .⑥大熊猫明显偏好原始林 .在全部 12个生态因子中 ,大熊猫对 11个因子的选择发生了改变 ,改变程度各不相同 .大熊猫在原始林中要回避的 9个生境类型 ,在次生林中变得随机选择 ;在原始林中随机选择的 6个生境类型 ,在次生林中变得偏好 .上述结果说明 ,对于原始林中回避或随机选择的生境特征 ,次生林中的大熊猫变成随机选择或偏好 .因此 ,大?  相似文献   

11.
Saccharin preference and performance in a Lashley III maze were found to be altered in adult male and female rats that had been exposed to alcohol during gestation. Specifically, the sexual dimorphism normally observed in both behaviors was absent in fetal alcohol-exposed animals. The lack of sexual dimorphism appeared to result from a masculinization of the exposed females and a feminization of the exposed males.  相似文献   

12.
Retrograde amnesia was produced in rats by electroconvulsive shock. Memory recovered if the animals were given repeated test trials. Memory did not recover if steps were taken to reduce the conditioning properties of the test trials; the manipulations included eliminating the response, altering the apparatus cues, or extinguishing conditioned "fear" by confining animals to the apparatus during the first test trial.  相似文献   

13.
分析城市消费者对低碳农产品的偏好、支付意愿及其偏好的异质性来源对减少碳排放、促进农业可持续发展意义重大。基于选择实验法,以牛奶为例,利用上海、南京和杭州786名城市消费者的调查数据,采用混合Logit模型,分析了习惯性购买常温奶或鲜牛奶两类消费群体对碳标签牛奶的偏好和支付意愿,探讨其偏好的异质性来源。结果表明,在消费者了解碳标签基本含义的前提下,两类消费群体对牛奶低碳和中碳标签均有显著正向偏好,并且牛奶低碳与全脂标签存在互补关系;常温奶和鲜牛奶消费群体对牛奶低碳标签的平均支付意愿分别为4.13元/盒和5.63元/盒。两类消费群体对牛奶碳标签的偏好具有异质性,且异质性来源不同。对常温奶消费群体而言,年龄越小、个人月收入越高、牛奶购买频率越高和对碳标签较熟识的消费者更倾向于购买低碳足迹牛奶;对鲜牛奶消费群体而言,男性、年龄越小、受教育程度越高和较为关注低碳信息的消费者购买碳足迹较低的牛奶的可能性更高。另外,消费者对低碳农产品作用的认知在两类消费群体中均正向影响其低碳偏好。因此,提出政府及相关机构应完善低碳产品认证制度、加强宣传推广碳标签的力度、向消费者普及低碳农产品相关知识、企业要注重低碳市场细分等政策建议。  相似文献   

14.
A Hein  R Held 《Science (New York, N.Y.)》1967,158(799):390-392
Kittens reared without sight of their limbs extended their forelimbs when carried down toward the edge of a horizontal surface. However, unlike normally reared kittens, they were not capable of guiding their paws accurately to the solid parts of an interrupted surface. This fractionation of the visually controlled placing response reveals that the guided reach requires an integration of sensorimotor systems not necessary for development of the elicited extension response.  相似文献   

15.
Pekin ducklings were tested with respect to their preference for approaching one of two simultaneously presented, rotating, silent duck decoys, painted in a variety of colors or patterns. Some of the ducklings had not been given any previous visual experience other than that gained in a 20-minute introduction to the empty apparatus; others had previously been given the opportunity to follow one particular decoy for 20 minutes. The decoys could be grouped into three categories: those in the first category were treated as equivalent, that is, so long as the duckling had followed one of these models it would approach either. The decoys of the second category were ones to which "imprinting" occurred, that is, the ducklings showed a decided preference for the model they had originally followed, whichever it was. The third category included models, one of which was always preferred, though the controls showed no such preference. The effects of the imprinting procedure vary with the stimuli presented.  相似文献   

16.
Familial imprinting determines H-2 selective mating preferences   总被引:15,自引:0,他引:15  
Inbred male mice typically prefer to mate with females of a different, non-self H-2 haplotype. To determine whether this natural preference is irrevocable or results from familial imprinting, a test system was used which relied on previous observations that B6 males (H-2b) mate preferentially with congenic B6-H-2k rather than B6 females, and B6-H-2k males with B6 females. This preference was reversed in B6 males fostered by B6-H-2k parents and in B6-H-2k males fostered by B6 parents, preference in these cases favoring the same H-2 type. Thus, H-2 selective mating preference is acquired by imprinting on familial H-2 types.  相似文献   

17.
Four monkeys with bilateral hippocampal lesions were trained to respond sequentially to visual stimuli, presented with an automated discrimination apparatus. Two different sequential tasks were presented. The experimental animals were significantly inferior on both problems to six control animals. Since no impairment appeared on simple visual discriminations presented with intertrial intervals from 5 seconds to 6 minutes, simple sensory deficits and "short-term" memory impairments appear unlikely. The results strengthen the interpretation that bilateral hippocampal lesions interfere with the acquisition of those behaviors which involve the execution of sequential responses.  相似文献   

18.
Rats administered 20 milligrams of magnesium pemoline per kilo gram of body weight learned to avoid shock in a jump-out apparatus in fewer trials than did controls. However, the results suggested that the principal effect of the drug was to facilitate the avoidance behavior of those animals that tended to "freeze" in response to electric grid shock. No differences in retention were observed between experimental and control animals that had achieved equal levels of learnine.  相似文献   

19.
Female preference predates the evolution of the sword in swordtail fish   总被引:1,自引:0,他引:1  
The study of female preferences and the evolution of male traits has until recently centered on genetic coevolutionary mechanisms. An alternative mechanism posits that a preference results from a preestablished bias in the female information-processing system arising from sources independent of sexual selection. Male traits then arise that are selected by this preexisting preference. The genus Xiphophorus consists of swordless platyfish and swordtails. Swordlessness is the primitive state. In this study, female platyfish, X. maculatus, were found to prefer conspecific males with artificial swords over those without swords, despite evidence that the common ancestor of platyfish and swordtails was swordless. These results suggest that the evolution of the sword in the swordtail clade was a consequence of selection arising from a preexisting bias.  相似文献   

20.
【目的】通过提高植物的多样性来引诱害虫、保护天敌是一种可持续控制害虫的有效途径。稻纵卷叶螟(Cnaphalocrocis medinalis)除水稻外,还可取食多种禾本科杂草,论文旨在利用稻纵卷叶螟对稻田周围不同杂草的喜好性,开发新型的稻纵卷叶螟防控策略。【方法】选取稻田生态系统常见的7种禾本科杂草(稗草Echinochloa crusgalli、秕谷草Leersia sayanuka、马唐Digitaria sanguinalis、牛筋草Eleusine indica、千金子Leptochloa chinensis、双穗雀稗Paspalum distichum和游草Leersia hexandra),于盆钵内人工栽培种植。将盆栽水稻和杂草植株置于纱笼中,接入初羽化的稻纵卷叶螟成虫,分别研究稻纵卷叶螟成虫在杂草与水稻之间的栖息选择性、产卵选择性,以及稻纵卷叶螟在各种杂草上的生物学特性。同时进行田间试验研究稻田田埂种植各种杂草条带(宽1 m)对稻纵卷叶螟成虫栖息、产卵分布的影响,通过赶蛾法调查杂草条带中及距离杂草条带1、5和10 m稻田中的稻纵卷叶螟蛾量,调查不同杂草条带中稻纵卷叶螟的产卵密度及卵被寄生率。【结果】稻纵卷叶螟成虫喜好趋向栖息于秕谷草和马唐,不喜好趋向双穗雀稗,在游草、牛筋草、稗草、千金子和水稻间,稻纵卷叶螟的栖息选择则没有偏向性。稻纵卷叶螟成虫在稗草、牛筋草、千金子、双穗雀稗、游草和水稻之间,偏向在水稻上产卵;秕谷草和水稻之间,偏向在秕谷草上产卵;马唐和水稻之间则没有明显的偏向性。稻纵卷叶螟在7种杂草上都能完成世代,但发育历期存在显著差异,在秕谷草上发育历期最短,双穗雀稗次之,游草、千金子、牛筋草、马唐、稗草和水稻上的发育历期间则没有显著性差异。不同寄主上的稻纵卷叶螟蛹重也存在差异,其中在马唐上的雌蛹、马唐和千金子上的雄蛹蛹重显著轻于在其他寄主植物上的蛹重。在不同寄主植物上稻纵卷叶螟的羽化率差异较大,秕谷草、游草、牛筋草、稗草和水稻上的羽化率为42.17%—51.31%,在千金子和双穗雀稗上最低,仅为11.76%和13.29%。雌性比以水稻和稗草上最高,显著高于其他寄主植物。大田试验表明,除了牛筋草和稗草外,其他杂草均能吸引稻纵卷叶螟栖息且在单位面积内的虫量显著高于稻田中的稻纵卷叶螟的数量。各种杂草上稻纵卷叶螟卵量差异显著,以秕谷草、游草、稗草和千金子上着卵量最多,每分蘖草上的着卵量达2.92—3.92粒,双穗雀稗和马唐分别为2.16和1.72粒,牛筋草最少。不同禾本科杂草上稻纵卷叶螟卵的被寄生率差异显著,介于21.90%—55.61%。其中,秕谷草和游草上的卵寄生蜂数量分别为1.47和1.42头/分蘖,为各种禾本科杂草上最高。【结论】秕谷草最具有成为防治稻纵卷叶螟的功能性植物的潜力,研究结果可为开发稻纵卷叶螟绿色防控新技术提供理论依据。  相似文献   

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