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1.
SUMMARY: Although dozens of biological ontologies have been created and deployed, relatively little attention has been given to using ontologies to represent behavior. Ontologies for two different behavior systems are described here. One ontology was a translation of a published ethogram, and the second was coded from video clips in a comparative study of jumping spider courtship. AVAILABILITY: http://mesquiteproject.org/ontology/.  相似文献   

2.
On mass behavior     
In imitative behavior, as studied previously by N. Rashevsky (Mathematical Biology of Sociol Behavior, Chapter XIII, The University of Chicago Press, 1950), the reason for the majority of a society to accept a particular behavior is based on purely voluntary action (band-wagon effect). In the present paper effects of coercion of the majority by a small minority group which poses the means for coercion, are studied. More general types of equations are thus obtained and threshold effects found, which bear a resemblance to some such effects studied previously.  相似文献   

3.
Chorioretinal thermal response to intense light exposure is calculated for light sources with a wide variety of spatial and temporal characteristics. Transient temperature distributions are computed by means of an alternating directions implicit method for solving cylindrically symmetric heat conduction problems in biological media. Chorioretinal thermal distributions are discussed in terms of a maximum temperature damage criterion for ocular tissue.  相似文献   

4.
Previous studies of effects of imitation on individuals in a population, in which the tendencies ϕ towards one or another of two mutually exclusive behaviors are distributed, are amplified by considering the distribution, not of ϕ directly, but of the excitations ɛ01 and ɛ02 of the two centers which mediate each of the two behaviors. It is shown how the distribution of ϕ is derived from those of ɛ01 and ɛ02. It is found that when both tendencies ɛ01 and ɛ02 are weak, the choice of one of the two behaviors not only is originally determined by pure chance, but that it is impossible to effect a change of the behaviour of a large population from one adopted behavior to a possible opposite one, by inhibiting the tendency towards the first behavior. Such a change by inhibition is possible only when the tendencies toward both mutually exclusive behaviors are sufficiently strong. A possible application to the persistency of irrelevant established behavior patterns, such as handshakes, is suggested.  相似文献   

5.
An evolutionarily informed perspective on parent-infant sleep contact challenges recommendations regarding appropriate parent-infant sleep practices based on large epidemiological studies. In this study regularly bed-sharing parents and infants participated in an in-home video study of bed-sharing behavior. Ten formula-feeding and ten breast-feeding families were filmed for 3 nights (adjustment, dyadic, and triadic nights) for 8 hours per night. For breast-fed infants, mother-infant orientation, sleep position, frequency of feeding, arousal, and synchronous arousal were all consistent with previous sleep-lab studies of mother-infant bed-sharing behavior, but significant differences were found between formula and breast-fed infants. While breast-feeding mothers shared a bed with their infants in a characteristic manner that provided several safety benefits, formula-feeding mothers shared a bed in a more variable manner with consequences for infant safety. Paternal bed-sharing behavior introduced further variability. Epidemiological case-control studies examining bed-sharing risks and benefits do not normally control for behavioral variables that an evolutionary viewpoint would deem crucial. This study demonstrates how parental behavior affects the bed-sharing experience and indicates that cases and controls in epidemiological studies should be matched for behavioral, as well as sociodemographic, variables.  相似文献   

6.
Observational studies of human conversations in relaxed social settings suggest that these consist predominantly of exchanges of social information (mostly concerning personal relationships and experiences). Most of these exchanges involve information about the speaker or third parties, and very few involve critical comments or the soliciting or giving of advice. Although a policing function may still be important (e.g., for controlling social cheats), it seems that this does not often involve overt criticism of other individuals’ behavior. The few significant differences between the sexes in the proportion of conversation time devoted to particular topics are interpreted as reflecting females’ concerns with networking and males’ concerns with self-display in what amount to a conventional mating lek.  相似文献   

7.
Allometry of behavior   总被引:1,自引:0,他引:1  
The study of allometric and size scaling relationships is well developed in most biological fields, but lags behind in the area of animal behavior. Part of the reason for this deficit is that scaling relationships of behaviors tend to be inherently more 'noisy' than other biological scaling relationships. However, body size has a pervasive influence on the performance of animals in their environments. For example, the frequently strong relationship between power-to-mass ratios and locomotor performance means that smaller species and individuals enjoy superior locomotor performance (burst acceleration and maneuverability) than larger species, particularly within a clade. We suggest that these size-related functional influences on performance profoundly influence many aspects of animal behavior, such as how animals forage, fight, flee, perceive danger, respond to risk and interact with other individuals. We outline exciting avenues for research on the allometry of behavior by integrating scaling and functional perspectives.  相似文献   

8.
It is shown that the linear equations of the formal theory of mass behavior proposed by the author in 1939 are first-order approximations of the biophysical theory proposed later. The second approximation contains cubic terms. It permits the expression of the time course of the change of behavior in terms of a quadrature.  相似文献   

9.
Bad behavior     
  相似文献   

10.
Model behavior     
Petsko GA 《Genome biology》2001,2(7):comment1009.1-comment10092
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11.
12.
This article penetrates the relationship between social behavior and rationality. A critical analysis is made of efforts to classify some behaviors as altruistic, as they simultaneously meet criteria of rationality by not truly being self-destructive. Newcomb's paradox is one attempt to create a hybrid behavior that is both irrational and still meets some criterion of rationality. Such dubious rationality is often seen as a source of altruistic behavior. Group selection is a controversial topic. Sober and Wilson (Unto Others--The Evolution and Psychology of Unselfish Behavior, Harvard University Press, Cambridge, MA, 1998) suggest that a very wide concept of group selection might be used to explain altruism. This concept also includes kin selection and reciprocity, which blurs its focus. The latter mechanisms hardly need further arguments to prove their existence. This article suggests that it is group selection in a strict sense that should be investigated to limit semantic neologism and confusion. In evaluation, the effort to muster a mechanism for altruism out of group selection has not been successful. However, this is not the end to group selection, but rather a good reason to investigate more promising possibilities. There is little reason to burden group selection with the instability of altruism caused by altruistic members of a group having lower fitness than egoistic members. Group selection is much more likely to develop in combination with group egoism. A common project is supported by incitement against free riding, where conformist members joined in solidarity achieve a higher fitness than members pursuing more individualistic options. Group egoism is in no conflict with rationality, and the effects of group selection will be supported rather than threatened by individual selection. Empirical evidence indicates a high level of traits such as conformism and out-group antagonism in line with group egoism. These traits are also likely candidates for behavior favored by group selection since they homogenize the group and link the different individuals closer to one another and a similar fate.  相似文献   

13.
Five different glucomannan samples were recrystallized from dilute solution. Depending on the experimental conditions, the crystals obtained could be identified as corresponding to the mannan I (anhydrous precipitate of more or less regular lozenge-shaped crystals) or mannan II (hydrated gel-forming pseudo-fibrillar precipitate). High-molecular-weight material, low temperature of crystallization, or a polar crystallization medium favored the mannan II polymorph, whereas a low-molecular weight, a high temperature of crystallization, and a crystallization medium of low polarity yielded the mannan I polymorph. Since the base-plane unit-cell dimensions are fairly constant with respect to variation of glucose, it is likely that isomorphous replacement of mannose by glucose occurs in glucomannan crystallization; the data also indicate that perfection of the glucomannan crystals was reduced in specimens having a high glucose:mannose ratio. The oriented crystallization of glucomannan on cellulose microfibrils was also studied under conditions where the mannan I polymorph was obtained. This gave shish-kebab structures that were characterized.  相似文献   

14.
15.
When sows kept under commercial conditions were put into crates in the early 1960s, the neuro-endocrine regulation of the maternal behavior in these domestic animals was disputed. Thus, the study of sow maternal behavior intensified and today a significant body of knowledge has accumulated to support the hormonal regulation of sow maternal behavior. The onset of nest building is associated with a periparturient decline in progesterone, an increase in prolactin and a major rise in plasma concentrations of PGF2alpha the day before parturition. Some nest building behaviors, such as pawing and gathering straw, have been found to correlate with changes in the levels of progesterone, prolactin and somatostatin. The duration of the birth process correlates negatively with peripheral oxytocin levels. During lactation, the stimuli from the piglets affect the release of several hormones which not only regulate the let down of milk but also sow metabolism and mammary milk production. The sow's nursing behavior ensures an even distribution of milk to her piglets. The piglets suckling behavior, in turn, is mainly a way to communicate their individual nutritional needs.  相似文献   

16.
Addictive behavior developes after repeated substance use and it typically include a strong desire to take the drug, difficulties in controlling its use, persisting in its use despite harmful consequences, a higher priority given to the drug use than to other activities. Relapse, the resumption of drug taking after periods of abstinence, remains the major problem for the treatment of addiction. The process of drug addiction shares striking commonalities with neural plasticity associated with natural reward learning and memory and is caused primarily by drug-induced sensitization in the brain mesocorticolimbic systems that attribute incentive salience to reward-associated stimuli. The switch from controlled to compulsive drug seeking represents a transition at the neural level from prefrontal cortical to striatal control. Current neurophysiologic evidence suggests that the development of addiction is to some extent due to neurochemical stimulation of the midbrain dopaminergic system that is traditionally considered as a 'common neural currency' for rewards of most kinds. Addictions are a result of the interplay of multiple genetic and environmental factors. They are characterized by phenotypic and genetic heterogeneity as well as polygenicity. Environmental factors are crucial in addiction vulnerability and resistese too.  相似文献   

17.
Specialization of the right cerebral hemisphere in man for analysis of spatial relations suggests that a similar specialization may exist in macaques. This possibility is being examined in animals first trained to negotiate a maze and then subjected to transection of optic chiasm and forebrain commissures. In the one successful experiment to date, clear evidence of such specialization was obtained for the left hemisphere in a monkey consistently using its left hand for retrieval of food. Provisional evidence for the existence of unilateral engrams in such circumstances was also obtained by limiting input during training to one eye and hemisphere and testing the other before and after completion of transection of the forebrain commissures. Finally, it was found that in the split brain macaque, a lesion in the parietal-occipital area of one hemisphere initially disrupted maze performance using either hemisphere.  相似文献   

18.
19.
Incubation temperature plays a prominent role in shaping the phenotypes and fitness of embryos, including affecting developmental rates. In many taxa, including turtles, eggs are deposited in layers such that thermal gradients alter developmental rates within a nest. Despite this thermal effect, a nascent body of experimental work on environmentally cued hatching in turtles has revealed unexpected synchronicity in hatching behavior. This review discusses environmental cues for hatching, physiological mechanisms behind synchronous hatching, proximate and ultimate causes for this behavior, and future directions for research. Four freshwater turtle species have been investigated experimentally, with hatching in each species elicited by different environmental cues and responding via various physiological mechanisms. Hatching of groups of eggs in turtles apparently involves some level of embryo-embryo communication and thus is not a purely passive activity. Although turtles are not icons of complex social behavior, life-history theory predicts that the group environment of the nest can drive the evolution of environmentally cued hatching.  相似文献   

20.
Chemotactic behavior of myoblasts   总被引:2,自引:0,他引:2  
Earlier studies have suggested that myogenic cells of somite origin migrate into the developing limb, but little is known about the factors affecting the pattern of migration. In order to understand the migratory behavior of myogenic cells, embryonic skeletal muscle cells were tested for their ability to migrate chemotactically using a modified Boyden chamber assay system. It is shown here, for the first time, that embryonic skeletal muscle cells have the capacity to migrate toward a gradient of platelet-derived growth factor (PDGF) and PDGF-like factors present in serum and chick embryo extract (CEE). On the other hand, nonmyogenic limb mesenchyme cells do not exhibit such a response. A hypothesis is proposed here that chemotactic factors from the already patterned vasculature might influence the distribution of skeletal muscle cells during early limb development.  相似文献   

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