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排序方式: 共有84条查询结果,搜索用时 15 毫秒
31.
水洞沟的新年代测定及相关问题讨论 总被引:13,自引:3,他引:10
水洞沟是中国北方的一处独具特色的旧石器时代晚期遗址,在阐释区域性技术传统的成因、远古文化的发展和变异,以及晚更新世人类在东北亚的迁徙、扩散和交流具有重要的地位。本文报道在水洞沟2号地点发现的新材料和新的研究成果:野外考察发现系列的火塘遗迹并采集到石制品、骨器等文化遗物;系统的AMS^14C测年将水沿沟遗址的年代确定在距今29000-24000前;新的研究为探讨水洞沟工业的渊源和细石器技术的起源提供了珍贵的信息。 相似文献
32.
Christopher W. Kuhar Tamara L. Bettinger Alan L. Sironen James H. Shaw Bill L. Lasley 《Zoo biology》2003,22(6):545-559
The captive population of Geoffroy's tamarins (Saguinus geoffroyi) has suffered a severe decline over the past 10 years. This population decline is attributed not to a failure to produce offspring, but rather to a failure to successfully rear offspring. To date, no studies have quantitatively examined the behaviors and hormones of this tamarin species in captivity. Therefore, this study was conducted to determine whether there were any discernable factors that could be correlated with failure to rear offspring in S. geoffroyi. Fifteen adult Geoffroy's tamarins (GTs) at the Cleveland Metroparks Zoo (CMZ) were observed by means of instantaneous sampling on a focal animal. In addition, all instances of social behaviors were recorded. A factorial arrangement of treatments was used, as animals were divided between a colony‐housing situation and a non‐colony situation with hand‐reared and mother‐reared animals in both treatments. Repeated‐measures analysis of variance (ANOVA) showed no interactions between the treatments, and no differences between rearing histories for the behaviors studied. However, animals housed in a colony setting exhibited higher levels of aggressive behaviors and lower activity levels compared to those in a non‐colony setting. There also was a trend for colony‐housed animals to huddle, scent‐mark, and exhibit sexual behaviors more often than non‐colony animals. First‐morning‐void urine samples were collected once per week, and assays for E1C and PdG indicated that reproduction was not being suppressed. ANOVA conducted on samples assayed for excreted cortisol showed no differences in mean cortisol concentration by rearing histories or housing conditions. While these physiological indicators reveal no signs of stress, high levels of aggressive and territorial behaviors indicate social unrest in the colony‐housed condition, which may be contributing to the poor reproductive success of those individuals. Zoo Biol 22:545–559, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
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Spatial selection refers to an animal's frequent use of certain areas of its enclosure or range. Through differential use of habitat, an individual can limit the amount of time spent in close proximity to other group members. The four adult female chimpanzees at the Tulsa Zoo were studied to determine if they used their enclosure differently from one another, if each had selected areas it occupied most frequently, and if an individual's preferred area was used by other female group members. Pairwise comparisons showed that the females used their island habitat differently from one another with the exception of one pair. Although these two females overlapped in their use of the enclosure, they separated their use temporally, thereby reducing the amount of time spent in close proximity to one another. Each female had a selected site that she occupied more frequently than did the other females. However, there was variation in the extent to which the females occupied each other's selected sites. Time of day and temperature had no effect on use of the habitat, however, one female showed a seasonal variation in her use of the enclosure. The spatial selection exhibited by these females may be comparable to the use of core areas by wild female chimpanzees. © 1994 Wiley-Liss, Inc. 相似文献
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36.
Maloney MA Leighty KA Kuhar CW Bettinger TL 《Journal of applied animal welfare science : JAAWS》2011,14(2):96-108
This study examined the impact of video presentations on the behavior of 4 silverback, western lowland gorillas (Gorilla gorilla gorilla). On each of 5 occasions, gorillas viewed 6 types of videos (blue screen, humans, an all-male or mixed-sex group engaged in low activity, and an all-male or mixed-sex group engaged in agonistic behavior). The study recorded behavioral responses and watching rates. All gorillas preferred dynamic over static videos; 3 watched videos depicting gorillas significantly more than those depicting humans. Among the gorilla videos, the gorillas clearly preferred watching the mixed-sex group engaged in agonistic behavior; yet, this did not lead to an increase in aggression or behavior indicating agitation. Further, habituation to videos depicting gorillas did not occur. This supports the effectiveness of this form of enrichment, particularly for a nonhuman animal needing to be separated temporarily due to illness, shipment quarantine, social restructuring, or exhibit modification. 相似文献
37.
Chen R Mias GI Li-Pook-Than J Jiang L Lam HY Chen R Miriami E Karczewski KJ Hariharan M Dewey FE Cheng Y Clark MJ Im H Habegger L Balasubramanian S O'Huallachain M Dudley JT Hillenmeyer S Haraksingh R Sharon D Euskirchen G Lacroute P Bettinger K Boyle AP Kasowski M Grubert F Seki S Garcia M Whirl-Carrillo M Gallardo M Blasco MA Greenberg PL Snyder P Klein TE Altman RB Butte AJ Ashley EA Gerstein M Nadeau KC Tang H Snyder M 《Cell》2012,148(6):1293-1307
38.
Tracy E. Blowers Jane M. Waterman Christopher W. Kuhar Tammie L. Bettinger 《Journal of Ethology》2010,28(2):287-294
Grouping is known to occur in many species of mammals, and the structure of groups can range along a continuum from basic
aggregations to complex social systems. Any social patterns that may occur within the group must be determined in order to
understand the adaptive nature of the group. Female Hippopotamus amphibius are known to aggregate in the wild, but their social behaviors are still not understood. Our objective was to determine if
captive female hippos display social structure within an aggregation by examining their interactions, and if kinship, familiarity,
and dominance influence these interactions. Behavioral data, using continuous focal animal sampling and scan sampling, were
collected on a group of captive female hippos housed at Disney’s Animal Kingdom and were used to analyze their interactions,
association patterns based on kinship and familiarity, and a dominance hierarchy. Our results support the hypothesis that
hippos exhibit social patterns due to the attraction to particular individuals. There were more associations between kin than
non-kin and also between individuals that were more familiar. Dominance patterns were also found among these hippos. These
results may aid in the general understanding of hippopotamus behavior and provide a framework for future research. 相似文献
39.
Summary Analytically pure hematoxylin (Htx), penta-acetylhematoxylin (PAHtx), and hematein (Hm) were isolated and characterized by 1H-NMR spectroscopy. The VIS/UV spectra of Htx and Hm were recorded in MeOH and in H2O at various pH values. The molar extinction coefficients of the long wavelength absorption bands are reported. The pK
a value for the 1st acidic dissociation step of Hm has been determined from the pH dependency of the absorption spectra of Hm in aqueous buffer solutions. Finally, the absorption spectra are qualitatively discussed. 相似文献
40.
Andrew G. Davies GinaMari G. Blackwell Richard C. Raabe Jill C. Bettinger 《Journal of visualized experiments : JoVE》2015,(98)
Alcohol use disorders are a significant public health concern, for which there are few effective treatment strategies. One difficulty that has delayed the development of more effective treatments is the relative lack of understanding of the molecular underpinnings of the effects of ethanol on behavior. The nematode, Caenorhabditis elegans (C. elegans), provides a useful model in which to generate and test hypotheses about the molecular effects of ethanol. Here, we describe an assay that has been developed and used to examine the roles of particular genes and environmental factors in behavioral responses to ethanol, in which locomotion is the behavioral output. Ethanol dose-dependently causes an acute depression of crawling on an agar surface. The effects are dynamic; animals exposed to a high concentration demonstrate an initial strong depression of crawling, referred to here as initial sensitivity, and then partially recover locomotion speed despite the continued presence of the drug. This ethanol-induced behavioral plasticity is referred to here as the development of acute functional tolerance. This assay has been used to demonstrate that these two phenotypes are distinct and genetically separable. The straightforward locomotion assay described here is suitable for examining the effects of both genetic and environmental manipulations on these acute behavioral responses to ethanol in C. elegans. 相似文献