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1.
New record of predatory behavior by the mandrill in Cameroon   总被引:4,自引:0,他引:4  
The predatory behavior of the mandrill (Mandrillus sphinx,Linnaeus 1758), a forestliving baboon, on the bay duiker (Cephalophus dorsalis,Gray 1864) was observed under natural conditions. In the predatory episode, at least two mandrills (one adult female and one adult male) attacked a bay duiker, but no overt aggressive interactions between the attackers occurred during consumption. The estimated predation pattern based on scars—intensive attacking of the head and pulling of the hind legs to eat the thigh muscles first—resembled the predation patterns of captive mandrills observed experimentally. The findings suggest that the predatory behavior is established in mandrills as a feeding behavior pattern as in savanna-living baboons. New data are thus presented which are relevant to the discussion of the origins of hunting behavior in early hominids.  相似文献   

2.
A bonnet troop inhabiting Lal Bagh, Bangalore (Hafeezur Rahaman & Parthasarathy, 1967) was exclusively studied for its communicative behavior. The whole system of the bonnet organization is based on composite expressions. Depending on situations, individual signals or a complex of them involving tactile, visual, auditory, and olfactory are passed from one individual to the other.Among tactile signals the most important one is the grooming; among visual the body movement, more particularly the face and jaws; among auditory the groaning and shrieking; among olfactory the sniffing.Analysis of such a study reveals that the bonnet monkeys have a communicative system and an organization of their own, which though principally are the same as in other primates, do entail a few minor differences. These features though primitive from the standards of human consideration, are developed to their full advantage, but still remain at a primitive level. By far, the greatest part of the whole system of communication seems to be devoted to the organization, of the social behavior of the group, to dominance and subordination, the maintenance of peace and cohesion of the group, reproduction and care of the young (Marler, 1965).  相似文献   

3.
On the use of hansen frequencies for estimating rates of behavior   总被引:1,自引:1,他引:0  
When the occurrence of a behavior is governed by aPoisson process over time, then the mean rate of behavior can be estimated usingHansen frequencies, which record whether the behavior has occurred at least once or not at all in each of several time periods. Here this estimate of the mean rate of behavior, based onHansen frequencies, is compared with the usual estimate, and its properties as an estimate of the mean rate of behavior are discussed in cases where the behavior is not governed by aPoisson process.This research was supported in part by Navy Grant N00014-67-A-0285-0009 to the Department of Statistics, University of Chicago, and by a grant from the Alfred P. Sloan Foundation to the Department of Theoretical Biology.  相似文献   

4.
In this paper the display (i.e., “branch-shaking”) behavior of three troops of Japanese monkeys—the confined Oregon troop as reported byModahl andEaton (1977), the semi-free-ranging Arashiyama West troop and the free-ranging Arashiyama B troop—are compared. The comparison reveals several similarities and dissimilarities between the Oregon troop and the two genetically related Arashiyama troops. The similarities include three display postures (shaking, kicking and leaping) and an increased frequency of male but not female displaying during the breeding season. The dissimilarities include the absence of two Oregon display postures (tossing and swinging) and collective displaying among Arashiyama monkeys. The hypothesis ofModahl andEaton (1977) that male displaying influences the females' choice of male mating partners is discussed. The evidence suggests the Oregon monkeys have incorporated male displaying into their socio-sexual behavior to a greater extent than Arashiyama monkeys. However, field observations indicate that males who migrate to the Arashiyama B site during the breeding season can influence female choice by “advertizing” their location with displays.  相似文献   

5.
Female mounting behavior was observed in the grape borerXylotrechus pyrrhoderus Bates (Coleoptera: Cerambycidae) under laboratory conditions. This behavior was directed towards either females (i.e., female homosexual mounting) or males. The female homosexual mounting was strongly elicited in females which had previously been allowed to fly. The frequency of this behavior was not related to the experience of mating. The investigation of the daily temporal pattern in female homosexual mounting activity indicated that the behavior most frequently occurred between 12∶00 and 16∶00, i.e., when females were searching for the pheromone-releasing males. Oviposition was also observed during this time interval. A detailed analysis revealed female mounting behaviors which are characteristic of male mounting behaviors, such as chasing conspecifics and synchronism of licking and abdominal bending. On the other hand, the frequency of male homosexual mounting was lower than that of females. Taken together with cases of other species previously reported, the expression of mounting behavior in females may be related to the evolution of the reproductive system, in which females approach their mates.  相似文献   

6.
Summary The properties of the choline transport system are fundamentally altered in saline solution containing 5mm imidazole buffer instead of 5mm phosphate: (i) The system no longer exhibits accelerated exchange. (ii) Choline in the external compartment fails to increase the rate of inactivation of the carrier by N-ethylmaleimide. (iii) Depending on the relative concentrations of choline and imidazole, transport may be activated or inhibited. The maximum rates are increased more than fivefold by imidazole, but at moderate substrate concentrations activation is observed with low concentrations of imidazole and inhibition with high concentrations. (iv) The imidazole effect is asymmetric, there being a greater tendency to activate exit than entry. All this behavior is predicted by the carrier model if imidazole is a substrate of the choline carrier having a high maximum transport rate but a relatively low affinity, and if imidazole rapidly enters the cell by simple diffusion, so that it can add to carrier sites on both sides of the membrane. Addition at thecis side inhibits, and at thetrans side activates. According to the carrier model, asymmetry is a necessary consequence of the potassium ion gradient in red cells, potassium ion being another substrate of the choline system.  相似文献   

7.
The N-methyl-d-aspartate (NMDA) receptors play key roles in excitatory neurotransmission and are involved in several important processes, including learning, behavior, and synaptic plasticity. The regulation of NMDA receptor neurotransmission has been extensively studied, but many important questions still remain unsolved. One of the most debated aspects of the NMDA receptor regulation relates to the identity, role, and cellular origin of the NMDA coagonist(s). In addition to glutamate, the NMDA receptor activity was believed to be regulated by the coagonist glycine. More recently, d-serine has also been proposed to play a role as a key coagonist for NMDA receptor activity and neurotoxicity. A surprising unique biosynthetic pathway for d-serine has been demonstrated, indicating the conservation of d-amino acid metabolism in mammals. d-Serine was originally shown to be exclusively made in astrocytes, indicating a possible role as a gliotransmitter. Nevertheless, recent data indicate that d-serine has a neuronal origin as well, which raises several new questions on d-serine disposition. In this review, I discuss recent advances in the field and propose a novel model of d-serine signaling that includes a bidirectional flow of d-serine between astrocytes and neurons. This review is dedicated to the memory of Dr. Marcos Wolosker.  相似文献   

8.
The combination of phase contrast photomicrography with a method for phase contrast observation of living sponges facilitated the initial photographic record of spongillid porocyte cellular behavior. Porocytes ofCorvomeyenia carolinensis Harrison (Spongillidae) exhibit true intracellular pores and are components of the incurrent system. The number of porocyte contractile vacuoles increases during pore dilation. This increase is possibly related to an increase in the amount of cell surface in contact with the hypotonic aqueous environment. The porocyte cell type appears closely related to, and is likely derived morphogenetically from, pinacocytes of the upper pinacoderm.  相似文献   

9.
Norbert Sauer 《Planta》1984,161(5):425-431
Glucose or non-metabolizable glucose analogues induce two systems of amino-acid transport in Chlorella vulgaris: an arginine-lysine system and a proline system. An additional third system of amino-acid transport is induced when glucose and an inorganic nitrogen source are present during glucose induction. The transport rates in glucose-NH 4 + -treated cells are 10 to 80 times higher than in untreated cells. The transport system shows a rather broad specificity and catalyses the transport of at least ten neutral and acidic amino acids. Three of these amino acids (l-alanine, l-serine and glycine) are transported by the proline system as well. The system is specific for l-amino acids and has a pH optimum between 5 and 6. Transport by this system seems to be active, since amino acids are accumulated inside the cells.  相似文献   

10.
F. W. Spiegel 《Protoplasma》1982,113(3):165-177
Summary The protostelidPlanoprotostelium aurantium Olive andStoianovitch has trophic cells which are either amoebae or flagellates. The general morphology and ultrastructure are consistent with what has been reported for otherEumycetozoa (protostelids, myxomycetes, and dictyostelids). The flagellar apparatus structure has the same basic pattern as that of other flagellate eumycetozoans. It shares with all these an anteriorly directed flagellum and centriole and microtubule arrays (MTA) 2–4. Unlike more primitive species which have two centrioles per flagellar apparatus,P. aurantium has only one. Also, the flagellar apparatus is independent of the nucleus inP. aurantium, not linked to it as in the primitive species. These features are useful in explaining the differences in swimming behavior betweenP. aurantium and biflagellate species. Evidence is presented to show thatP. aurantium is closely related to the non-flagellateProtostelium mycophaga Olive andStoianovitch.This research represents part of a Ph.D. dissertation presented to the University of North Carolina.  相似文献   

11.
The paper examinesBateson’s idea that social relationships can be described according to the degree that behavior is symmetric (mutual) or complementary (non-mutual). It was suggested that in primates complementary relationships are most typical and stable.Bateson’s definitions were quantified and applied to observations of paired rhesus females, showing that familiar dyads had complementary relationships, probably reflecting social status, while unfamiliar dyads had symmetric relationships. Phases of this project were supported by U. S. P. H. S. grants, MH-17052 (toE. W. Hansen) and MH-00322 (Postdoctoral Fellowship).  相似文献   

12.
The high throughput of structure determination pipelines relies on increased automation and, consequently, a reduction of time spent on interactive quality control. In order to meet and exceed current standards in model accuracy, new approaches are needed for the facile identification and correction of model errors during refinement. One such approach is provided by the validation and structure-improvement tools of the MOLPROBITY web service. To test their effectiveness in high-throughput mode, a large subset of the crystal structures from the SouthEast Collaboratory for Structural Genomics (SECSG) has used protocols based on the MOLPROBITY tools. Comparison of 29 working-set and 19 control-set SECSG structures shows that working-set outlier scores for updated Ramachandran-plot, sidechain rotamer, and all-atom steric criteria have been improved by factors of 5- to 10-fold (relative to the control set or to a Protein Data Bank sample), while quality of covalent geometry, Rwork, Rfree, electron density and difference density are maintained or improved. Some parts of this correction process are already fully automated; other parts involve manual rebuilding of conformations flagged by the tests as trapped in the wrong local minimum, often altering features of functional significance. The ease and effectiveness of this technique shows that macromolecular crystal structures from either traditional or high-throughput determinations can feasibly reach a new level of excellence in conformational accuracy and reliability.  相似文献   

13.
Forelimb dissections on 14 genera of anthropoids including humans and 17 cases of human aneuploids has revealed a high incidence of “atavistic” musculature (Barash et al., 1970;Aziz, 1981a) in the aneuploids. The phenotypic specificity of this aneuploid musculature clearly manifests developmental retardation and instability (Shapiro, 1983) revealing not only the likely course of embryonic myogenesis in chromosomally normal humans (Cihak, 1972, 1977) but also information relevant to ontogenetic and evolutionary changes. The extensor digitorum profundus proprius complex is particularly illustrative of these characteristics of aneuploid musculature. Our examination of the variation of this muscle complex in human aneuploids and between primate genera reveals how normal ontogeny may proceed, as well as the morphological basis for the evolutionary changes in hand structure and function amongst Primates. We also consider the phylogenetic and functional significance of changes in the extensor digitorum profundus proprius with reference to the divergent locomotory and manipulative capabilities and behavior of Primates.  相似文献   

14.
Heavy metals cause irreversible neurobehavioral damage in many developing mammals, but the mechanisms of this damage are unknown. The influence of three heavy metal compounds, triethyllead chloride, lead acetate and cadmium chloride, on lethality, development, behavior and learning was studied using the fruit fly,Drosophila melanogaster. This animal was used because it allows hundreds of subjects to be assayed very easily in individual experiments and because it is a system in which toxicological questions might be answered by using the techniques of modern molecular genetics. When triethyllead chloride, lead acetate or cadmium chloride was placed in the medium, the larval LC50 (± standard error) was found to be 0.090±0.004, 6.60±0.64 and 0.42±0.04mm, respectively. Each of the tested compounds produced a dose-related delay in development. In particular, they caused a delay in the development of larvae to pupae. When larvae were reared on medium containing triethyllead chloride (0.06mm), lead acetate (3.07mm) or cadmium chloride (0.11mm), phototaxis, locomotion and learning were not inhibited. Since significant neurobehavioral effects were not observed under the experimental conditions used,Drosophila does not appear to be an appropriate animal for the genetic dissection of such effects of heavy metals during development.  相似文献   

15.
Kaplan andZucker (1980) argued that dominance and kinship do not function as important organizing features for intragroup behavior and social structure among patas monkeys (Erythrocebus patas). This paper reviews the available data pertinent to this argument and concludes that dominance probably is not a reliable structural variable for captive patas, despite its clear development in most groups. In contrast, kinship is a major organizing feature that strongly affects allogrooming and other affiliative interactions, and socialization.  相似文献   

16.
One-zero (Hansen) frequency, the proportion of time samples during which a certain behavior occurs, measures a linear combination of prevalence (the proportion of time an animal spends in a behavior) and of incidence (the number of bouts of a behavior per hour) with a non-negligible perturbation due to the clustering characteristics of behavior relative to the time interval length. The exact relationship is derived theoretically and demonstrated empirically usingLeger's data base of chimpanzee behavior. It is recommended that, whenever possible, time sampling methods other than One-zero Sampling be used in the study of behavior.  相似文献   

17.
Previous investigations from this laboratory have demonstrated that hypophysectomy induces up-regulation of neuronal nitric oxide synthase (nNOS) in magnocellular neurons of the mammalian hypothalamo-neurohypophyseal system (HNS). Accompanied by this upregulation of nNOS, both neuronal regeneration and degeneration are also observed in this system following hypophysectomy. The specific aim of this study was to determine the potential role of nNOS upregulation in neuronal survival and regeneration after hypophysectomy in the adult Sprague–Dawley (SD) rat by using a competitive nitric oxide synthase blocker, N(G)-nitrol-l-arginine methyl ester (l-NAME). We found that l-NAME treatment effectively blocked the regeneration of magnocellular neurons of the rodent hypothalamus as observed in the lumen of the third cerebral ventricle following hypophysectomy. However, l-NAME had no effect on the survival of magnocellular neurons in the supraoptic (SON) and paraventricular (PVN) nuclei after hypophysectomy. These results suggest that the induced increase of nNOS expression enhance the regenerative ability of magnocellular neurons of the HNS following hypophysectomy.  相似文献   

18.
Summary Successive staining of cells of the enterochromaffin system of the guinea pig by an argentaffin and an argyrophile method shows that, as in man and rabbit, they can be divided into (a) those in which all granules are apparently argentaffin, (b) those in which all granules are argyrophile but none are argentaffin, and (c) those in which some granules are argentaffin (as well as argyrophile) while others are purely argyrophile. The presence of the third type makes it evident that no hard and fast line of distinction can be drawn between the so called argentaffin and argyrophile cells.I am grateful to Mr. Mohan Lal Sharma for help with the photographs and to Mr. Anand Parkash for technical assistance.  相似文献   

19.
Although they are effective at treating the motor impairments that are the core symptoms of Parkinson’s disease, current treatments, namely l-3,4-dihydroxyphenylalanine (l-DOPA), the gold standard medication and high-frequency stimulation of the subthalamic nucleus (HFS-STN), can lead to cognitive and mood alterations. Many of these side effects, such as depression, anxiety and sleep disturbances, could be related to abnormal functioning of the serotonergic system, but much basic research remains to be done. Molecular studies in humans and animal models of the disease have reported diverse drastic changes to the serotonergic system. It has also been shown that the serotonergic system both plays a major role in the mechanism of action of the current therapies and is altered by the therapies. It has been reported that HFS-STN decreases serotonin release in several regions, mostly via inhibition of serotonergic neuron activity. The involvement of serotonergic neurons in l-DOPA treatment is even more significant. First, serotonergic neurons, able to convert exogenous l-DOPA to dopamine, are a major site to release dopamine throughout the brain. Second, the substitution of serotonin by newly synthesized dopamine in serotonin neurons leads to acute and chronic alteration of serotonin release and metabolism. Therefore, both therapeutic approaches, via distinct mechanisms, decrease serotonergic system activity and, rather than alleviating cognitive or mood disorders, tend to aggravate them. Molecular strategies targeting the serotonergic system are being developed and could be decisive in limiting l-DOPA-induced dyskinesia, as well as mood and cognitive symptoms produced by antiparkinsonian therapies.  相似文献   

20.
Behavioral and pharmacological effects of oral administration ofl-deprenyl in the dog are described. Spontaneous behavior is unaffected at doses below 3 mg/kg while at higher doses there was stereotypical responding. There was evidence of improved cognitive function in animals chronically treated with a 1 mg/kg dose but the effectiveness varied considerably between subjects. Chronic administration produced a dose dependent inhibition in brain, kidney and liver monoamine oxidase B, and had no effect on monoamine oxidase A. There were also dose dependent increases in brain phenylethylamine and in plasma levels of amphetamine. Dog platelets did not have significant levels of MAO-B. Brain dopamine and serotonin metabolism were unaffected byl-deprenyl at doses up to 1 mg/kg. It appears that for the dog, deamination of catecholamines is controlled by MAO-A. Nevertheless, it is suggested thatl-deprenyl serves as a dopaminergic agonist, and there is also evidence that it affects adrenergic transmission. These catecholaminergic actions may account for the effects ofl-deprenyl on behavior and cognitive function.  相似文献   

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