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1.
A horizontal plexiglas tube containing a food-reward was presented to four naive tufted capuchins and suitable sticks were
provided to push the reward out. Three monkeys out of four spontaneously used the tools and showed very different styles of
solving the task. In more complex conditions, in which the sticks needed to be combined or actively modified in order to become
effective, the monkeys were always successful; however, their performance was loaded with errors which did not disappear throughout
the trials. Evidence of a difference between success in solving the problem and its understanding was found. This suggests
that although capuchins can discover new means through active experimentation, they do not mentally represent the characteristics
necessary for a tool to be effective, nor do they modify the tool appropriately beforehand. At this level, a major difference
with chimpanzees emerges. 相似文献
2.
Development of tool use in a macaque and a gorilla 总被引:3,自引:0,他引:3
Francesco Natale Patrizia Poti' Giovanna Spinozzi 《Primates; journal of primatology》1988,29(3):413-416
The development of the capacity to use a stick as a tool was tested in a macaque (Macaca fuscata) and a gorilla (Gorilla gorilla gorilla) infants that had previously shown to be able to use strings and supports as dragging tools. Subjects were tested between
15 and 38 months of age. Different levels of competence between the subjects emerged over testing. The macaque developed a
stereotyped strategy to cope with the problem, only getting random successes, whilst the gorilla developed a flexible strategy
and revealed to be able to mentally represent the solution of the problem. In fact, when not successful using the stick, the
gorilla thought out an alternative strategy, choosing and adapting a new object to use it as a tool. 相似文献
3.
Klaus Zuberbühler Lorenz Gygax Nerida Harley Hans Kummer 《Primates; journal of primatology》1996,37(1):1-12
In a captive group of long-tailed macaques, tool-using behavior by a single competent individual had a significant effect on the synchronous manipulative behavior of naïve animals. Group members engaged in manipulations on the same object class more frequently during times when the model was working than when it was not. The form of their behavior, however, in no way resembled the technique used by the model. All three animals that later became successful tool users were among the few subjects that exhibited a significant increase in manipulations on the same object class while the model was working. Possible causal relationships between this stimulus enhancement and the transmission of the new behavior to other group members are analyzed and discussed. 相似文献
4.
Takashi Torigoe 《Primates; journal of primatology》1985,26(2):182-194
Seventy-four primates species (24 genera of six families) were presented with a nylon rope and a wooden cube, and their subsequent
manipulations were recorded in detail. Five hundreds and six manipulation patterns were distinguished on the basis of the
actions performed, body-parts used and relations to other objects. Inter-specific comparisons revealed three groups: (1) lemurs,
marmosets, spider monkeys and leaf-eaters; (2) Old World monkeys except leaf-eaters; and (3) cebus monkeys and apes. The first
group had the smallest repertoire of manipulations, in which only a few types of actions and body-parts were involved. The
second and third groups had more varied modes of manipulation. Actions such as Roll, Rub and Slide, and use of fingers characterized
these groups. Except for the lesser ape, their manipulations were frequently related with other objects. Moreover, actions
such as Drape, Drop, Strike, Swing and Throw were typical of the third group. The factors producing such inter-specific differences
in manipulations and the relations to tool use are discussed. 相似文献
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7.
This work presents the Protein Association Analyzer (PRASA) (http://zoro.ee.ncku.edu.tw/prasa/) that predicts protein interactions as well as interaction types. Protein interactions are essential to most biological functions. The existence of diverse interaction types, such as physically contacted or functionally related interactions, makes protein interactions complex. Different interaction types are distinct and should not be confused. However, most existing tools focus on a specific interaction type or mix different interaction types. This work collected 7234058 associations with experimentally verified interaction types from five databases and compiled individual probabilistic models for different interaction types. The PRASA result page shows predicted associations and their related references by interaction type. Experimental results demonstrate the performance difference when distinguishing between different interaction types. The PRASA provides a centralized and organized platform for easy browsing, downloading and comparing of interaction types, which helps reveal insights into the complex roles that proteins play in organisms. 相似文献
8.
西沟湾1号旧石器地点位于河北省张家口市怀来县官厅镇珠窝园村,埋藏于永定河右岸第二级阶地后缘。2015年8-9月对该地点进行试掘,揭露面积约27m2,出土232件石制品和19件动物化石。石制品原料以粗面岩为主,应为就地取材;类型包括石核、石片、断块等,标本大小总体以小型为主;石核剥片均采用硬锤锤击法。石制品的类型和技术特征显示其总体属于石片石器技术体系。结合遗物和堆积状况,推测西沟湾1号地点为一处原地埋藏类型的临时性石制品剥片场所。依碳十四年代测定,初步推断该地点的时代为旧石器时代晚期。 相似文献
9.
10.
《Saudi Journal of Biological Sciences》2022,29(4):1981-1997
The emergence of coronavirus disease 2019 (COVID-19) pandemic in Wuhan city, China at the end of 2019 made it urgent to identify the origin of the causal pathogen and its molecular evolution, to appropriately design an effective vaccine. This study analyzes the evolutionary background of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 or SARS-2) in accordance with its close relative SARS-CoV (SARS-1), which was emerged in 2002. A comparative genomic and proteomic study was conducted on SARS-2, SARS-1, and Middle East respiratory syndrome coronavirus (MERS), which was emerged in 2012. In silico analysis inferred the genetic variability among the tested viruses. The SARS-1 genome harbored 11 genes encoding 12 proteins, while SARS-2 genome contained only 10 genes encoding for 10 proteins. MERS genome contained 11 genes encoding 11 proteins. The analysis also revealed a slight variation in the whole genome size of SARS-2 comparing to its siblings resulting from sequential insertions and deletions (indels) throughout the viral genome particularly ORF1AB, spike, ORF10 and ORF8. The effective indels were observed in the gene encoding the spike protein that is responsible for viral attachment to the angiotensin-converting enzyme 2 (ACE2) cell receptor and initiating infection. These indels are responsible for the newly emerging COVID-19 variants αCoV, βCoV, γCoV and δCoV. Nowadays, few effective COVID-19 vaccines developed based on spike (S) glycoprotein were approved and become available worldwide. Currently available vaccines can relatively prevent the spread of COVID-19 and suppress the disease. The traditional (killed or attenuated virus vaccine and antibody-based vaccine) and innovated vaccine production technologies (RNA- and DNA-based vaccines and viral vectors) are summarized in this review. We finally highlight the most common questions related to COVID-19 disease and the benefits of getting vaccinated. 相似文献