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1.
草原蝗虫的栖境选择   总被引:2,自引:0,他引:2  
颜忠诚  陈永林 《动物学报》1997,43(1):110-111
Habital selection is the behavioural chiice of a type of space where the animals prefer to live. It is obviousthat all animals are found in a more or less restricted range of suitable environment. The way in which animalpopulation selects a habitat may have important effects on obtaining food or mating, its vulnerability to preda-tors, its exposure to climatic stress,and so on. Different habitat selection is one of the principal relationshipswhich permit a species to exist, and it is one of the very important behaviour and ecological characteristics of  相似文献   

2.
The world is projected to experience an approximate doubling of atmospheric CO_2 concentration in the next decades. Rise in atmospheric CO_2 level as one of the most important reasons is expected to contribute to raise the mean global temperature 1.4 ℃-5.8 ℃ by that time. A survey from 128 countries speculates that global warming is primarily due to increase in atmospheric CO_2 level that is produced mainly by anthropogenic activities. Exposure of animals to high environmental temperatures is mostly accompanied by unwanted acceleration of certain biochemical pathways in their cells. One of such examples is augmentation in generation of reactive oxygen species(ROS) and subsequent increase in oxidation of lipids, proteins and nucleic acids by ROS. Increase in oxidation of biomolecules leads to a state called as oxidative stress(OS). Finally, the increase in OS condition induces abnormality in physiology of animals under elevated temperature. Exposure of animals to rise in habitat temperature is found to boost the metabolism of animals and a very strong and positive correlation exists between metabolism and levels of ROS and OS. Continuous induction of OS is negatively correlated with survivability and longevity and positively correlated with ageing in animals. Thus, it can be predicted that continuous exposure of animals to acute or gradual rise in habitat temperature due to global warming may induce OS, reduced survivability and longevity in animals in general and poikilotherms in particular. A positive correlation between metabolism and temperature in general and altered O_2 consumption at elevated temperature in particular could also increase the risk of experiencing OS in homeotherms. Effects of global warming on longevity of animals through increased risk of protein misfolding and disease susceptibility due to OS as the cause or effects or both also cannot be ignored. Therefore, understanding the physiological impacts of global warming in relation to longevity of animals will become very crucial challenge to biologists of the present millennium.  相似文献   

3.
Learning and memory is a delicate process of acquiring, storing and reconsolidating the knowledge with a behavioral output, which is indispensable for animals to adapt to their living environment. Defects in learning and memory contribute to some psychiatric disorders such as schizophrenia, depression and Alzheimer’s disease, and are recently reported to be inheritable from the parental generation to their offspring. However, it is not clear currently what the mechanism is underlying the learning and memory inheritance due to the lack of animal models. In this perspective type of mini-review, we first briefly summarize the current understanding of the molecular basis, neural circuit and transgenerational inheritance of learning and memory. We then focus on discussing the possibility of using Drosophila as an animal model to study the transgenerational inheritance of learning and memory and propose potential strategies to achieve the goal.  相似文献   

4.
<正>There is no experiencing without an experiencer,the self.Whether the experiencer knows it is"the self"that is experiencing is a different and tricky philosophical issue.Dating back to Ivan Pavlov’s dogs,the"experience"of animals has  相似文献   

5.
6.
This paper proposes a route optimization method to improve the performance of route selection in Vehicle Ad-hoc Network (VANET). A novel bionic swarm intelligence algorithm, which is called ant colony algorithm, was introduced into a traditional ad-hoc route algorithm named AODV. Based on the analysis of movement characteristics of vehicles and according to the spatial relationship between the vehicles and the roadside units, the parameters in ant colony system were modified to enhance the performance of the route selection probability rules. When the vehicle moves into the range of several different roadsides, it could build the route by sending some route testing packets as ants, so that the route table can be built by the reply information of test ants, and then the node can establish the optimization path to send the application packets. The simulation results indicate that the proposed algorithm has better performance than the traditional AODV algorithm, especially when the vehicle is in higher speed or the number of nodes increases.  相似文献   

7.
t Social insects have evolved colony behavioral, physiological, and organiza. tional adaptations (social immunity) to reduce the risks of parasitization and/or disease transmission. The collection of resin from various plants and its use in the hive as propolis is a clear example of behavioral defense. For Apis mellifera, an increased propolis content in the hive may correspond to variations in the microbial load of the colony and to a downregulation of an individual bee's immune response. However, many aspects of such antimicrobial mechanism still need to be clarified. Assuming that bacterial and fungal infection mechanisms differ from the action of a parasite, we studied the resin collection dynamics in Varroa destructor-infested honeybee colonies. Comparative experiments involving hives with different mite infestation levels were conducted in order to assess the amount of resin collected and propolis quality within the hive, over a 2-year period (2014 and 2015). Our study demonstrates that when A. mellifera colonies are under stress because of Varroa infestation, an increase in the number of resin foragers is recorded, even if a general intensification of the foraging activity is not observed. A reduction in the total polyphenolic content in propolis produced in infested versus uninfested hives was also noticed. Considering that different propolis types show varying levels of inhibition against a variety of honey bee pathogens in vitro, it would be very important to study the effects against Varroa of two diverse types of propolis: from Varroa-free and from Varroa-infested hives.  相似文献   

8.
D-xylose is a necessary sugar for animals. The xylanase from a mollusk, Ampullaria crossean, was previously reported by our laboratory. This xylanase can degrade the xylan into D-xylose. But there is still a gap in our knowledge on its metabolic pathway. The question is how does the xylose enter the pentose pathway? With the help of genomic databases and bioinformatic tools, we found that some animals, such as bacteria, have a highly conserved D-xylose isomerase (EC 5.3.1.5). The xyiose isomerase from a sea squirt, Ciona intestinali, was heterogeneously expressed in Escherichia coli and purified to confirm its function. The recombinant enzyme had good thermal stability in the presence of Mg^2+. At the optimum temperature and optimum pH environment, its specific activity on D-xylose was 0.331 μmol/mg/min. This enzyme exists broadly in many animals, but it disappeared in the genome of Amphibia-like Xenopus laevis. Its sequence was highly conserved. The xylose isomerases from animals are very interesting proteins for the study of evolution.  相似文献   

9.
Behavioral research has long had an important role in the conservation of terns (Ayes: Stemidae). Habitat management and restoration of breeding colony sites depends on knowledge of the cues used to select colony and nest sites. For example, conspecific attraction with playback and decoys is commonly used to bring terns to suitable colony sites and habitat modification is often used to increase the availability of suitable nest sites. Tern colonies are interconnected by dispersal, and a metapopulation approach is needed for effective management. Population dynamics are therefore affected by behaviors that influence the frequency of movement among colony sites: site fidelity, natal and breeding dispersal, and group adherence. The monogamous breeding system of terns should keep effective population size similar to census population size, but variation in sex ratios (likely resulting from sex differences in behavior) and in parental quality can result in a smaller than expected effective population size. In addition to the behavior of terns, knowledge of the behavior of predators on terns contributes to management plans, because predator behavior can sometimes be manipulated and predation is often performed by only a few specialized individuals. Other examples of links between tern behavior and conservation are also briefly reviewed, such as behavioral toxicology research and studies of behavioral responses to human disturbance and manmade structures. More work is needed on the behavior of migratory terns at staging sites, stopover sites and wintering grounds, and on the behavior of less well-studied species and species in less well-studied geographic regions [Current Zoology 60 (4): 500-514, 2014].  相似文献   

10.
Significant progress has been made in understanding pharmacokinetics (PK),pharmacodynamics (PD),as well as toxicity profiles of therapeutic proteins in animals and humans,which have been in commercial development for more than three decades.However,in the PK arena,many fundamental questions remain to be resolved.Investigative and bioanalytical tools need to be established to improve the translation of PK data from animals to humans,and from in vitro assays to in vivo readouts,which would ultimately lead to a higher success rate in drug development.In toxicology,it is known,in general,what studies are needed to safely develop therapeutic proteins,and what studies do not provide relevant information.One of the major complicating factors in nonclinical and clinical programs for therapeutic proteins is the impact of immunogenicity.In this review,we will highlight the emerging science and technology,as well as the challenges around the pharmacokinetic-and safety-related issues in drug development of mAbs and other therapeutic proteins.  相似文献   

11.
γ-Tubulin is an essential component of the microtubule organizing center (MTOC) responsible for nucleating microtubules in both plants and animals. Whereas γ-tubulin is tightly associated with centrosomes that are inheritable organelles in cells of animals and most algae, it appears at different times and places to organize the myriad specialized microtubule systems that characterize plant cells. We have traced the distribution of γ-tubulin through the cell cycle in representative land plants (embryophytes) and herein present data that have led to a concept of the pleiomorphic and migratory MTOC. The many forms of the plant MTOC at spindle organization constitute pleiomorphism, and stage-specific “migration” is suggested by the consistent pattern of redistribution of γ-tubulin during mitosis. Mitotic spindles may be organized at centriolar centrosomes (only in final divisions of spermatogenesis), polar organizers (POs), plastid MTOCs, or nuclear envelope MTOCs (NE-MTOCs). In all cases, with the possible exception of centrosomes in spermatogenesis, the γ-tubulin migrates to broad polar regions and along the spindle fibers, even when it is initially a discrete polar entity. At anaphase it moves poleward, and subsequently migrates from polar regions (distal nuclear surfaces) into the interzone (proximal nuclear surfaces) where interzonal microtubule arrays and phragmoplasts are organized. Following cytokinesis, γ-tubulin becomes associated with nuclear envelopes and organizes radial microtubule systems (RMSs). These may exist only briefly, before establishment of hoop-like cortical arrays in vegetative tissues, or they may be characteristic of interphase in syncytial systems where they serve to organize the common cytoplasm into nuclear cytoplasmic domains (NCDs).  相似文献   

12.
Portal vein thrombosis (PVT) is a common complication of liver cirrhosis. Gao et al. [1] reported that the prevalence of PVT in patients with cirrhosis is 8.82%. With the rapid developments in image-based diagnostic technology, the diagnosis rate of PVT is gradually increasing [2]. A follow-up study of 1243 patients with cirrhosis revealed that the cumulative incidences of PVT at 1, 3, and 5 years are 4.6%, 8.2%, and 10.7%, respectively [3]. PVT is a life-threatening factor for patients with cirrhosis, leading to portal hypertension and aggravating gastrointestinal hemorrhage [4]. The prevention of PVT has become a focus of clinical concern nowadays. It is well known that the establishment of animal models is the basis of scientific research. However, it is currently difficult to establish PVT models in large animals. Thereby, the establishment of a stable PVT animal model to study PVT is urgent and significant. We successfully established a new canine model of PVT involving the injection of an autologous thrombus through an indwelling catheter in the portal vein. This model is reliable for further studies of surgical treatment and drug therapy for PVT.  相似文献   

13.
Fear and anxiety may be adaptive responses to life-threatening situations, and animals may communicate fear to others vocally. A fundamental understanding of fear inducing sounds is important for both wildlife conservation and management because it helps us understand how to design repellents and also how (and why) animals may be negatively impacted by anthropogenic sounds. Nonlinear phenomena--sounds produced by the desynchronization of vibrations in a sound production system-are commonly found in stress-induced animal vocalizations, such as in alarm calls, mobbing calls, and fear screams. There are several functional hypotheses for these nonlinear phenomena. One specific hypothesis is the unpredictability hypothesis, which suggests that because nonlinear phenomena are more variable and somewhat unpredictable, animals are less likely to habituate to them. Animals should, therefore, have a prolonged response to sounds with nonlinear phenomena than sounds without them. Most of the studies involving nonlinear phenomena have used mammalian subjects and conspecific stimuli. Our study fo- cused on white-crowned sparrows (Zonotrichia leucophrys ssp. oriantha) and used synthesized acoustic stimuli to investigate behavioral responses to stimuli with and without nonlinear phenomena. We predicted that birds would be less relaxed after hearing a stimulus with a nonlinear component. We calculated the difference from baseline of proportion of time spent in relaxed behaviors and performed pair-wise comparisons between a pure tone control stimulus and each of three experimental stimuli, including a frequency jump up, a frequency jump down, and white noise. These comparisons showed that in the 30q50 s after the playback experiment, birds were significantly less relaxed after hearing noise or an abrupt frequency jump down an octave but not an abrupt frequency jump up an octave or a pure tone. Nonlinear phenomena, therefore, may be generally arousing to animals and may explain why these acoustic properties are commonly fou  相似文献   

14.
Understanding how human cardiomyocytes mature is crucial to realizing stem cell-based heart regeneration, modeling adult heart diseases, and facilitating drug discovery. However, it is not feasible to analyze human samples for maturation due to inaccessibility to samples while cardiomy-ocytes mature during fetal development and childhood, as well as difficulty in avoiding variations among individuals. Using model animals such as mice can be a useful strategy;nonetheless, it is not well-understood whether and to what degree gene expression profiles during maturation are shared between humans and mice. Therefore, we performed a comparative gene expression analysis of mice and human samples. First, we examined two distinct mice microarray platforms for shared gene expression profiles, aiming to increase reliability of the analysis. We identified a set of genes display-ing progressive changes during maturation based on principal component analysis. Second, we demonstrated that the genes identified had a differential expression pattern between adult and ear-lier stages (e.g., fetus) common in mice and humans. Our findings provide a foundation for further genetic studies of cardiomyocyte maturation.  相似文献   

15.
Cases of imperfect or non-model mimicry are common in plants and animals and challenge intuitive assumptions about the nature of directional selection on mimics. Many non-rewarding flower species do not mimic a particular species, but at- tract pollinators through 'generalised food deception'. Some predatory animals also attract pollinators by resembling flowers, perhaps the most well known, yet least well understood, is the orchid mantis Hymenopus coronatus. This praying mantis has been hypothesised to mimic a flower corolla and we have previously shown that it attracts and captures pollinating insects as prey. Predatory pollinator deception is relatively unstudied and whether this occurs through model mimicry or generalised food decep- tion in the orchid mantis is unknown. To test whether the orchid mantis mimics a specific model flower species we investigated similarities between its morphology and that of flowers in its natural habitat in peninsular Malaysia. Geometric morphometrics were used to compare the shape of mantis femoral lobes to flower petals. Physiological vision models were used to compare the colour of mantises and flowers from the perspective of bees, flies and birds. We did not find strong evidence for a specific model flower species for the orchid mantis. The mantis' colour and shape varied within the range of that exhibited by many flower pet- als rather than resembling one type in particular. We suggest that the orchid mantis resembles an average, or generalised flower-like stimulus. Thus predatory pollinator deception in the orchid mantis is likely to function as a form of generalised food deception, as opposed to model mimicry .  相似文献   

16.
1 Technology of natural materials Early man used conveniently shaped stones as tools. "Workshop" areas have been found with large numbers of stones, some showing signs of being worked. However, organic materials like wood will decay under normal wet conditions in the presence of oxygen, so we won't find the same sort of evidence for wooden tools. It is safe to assume that early man used sticks as probes and clubs, and maybe even for making some sort of nestlike protection against the elements and predators, since we see chimpanzees and other animals doing this sort of thing. So wood, and ahnost certainly other plant materials such as fibrous leaves, and bone and other materials gleaned from dead animals, would be used from the earliest times. We need to know this in order to establish the idea that Man can be expected to have a long history of the use and manipulation of natural materials. This needs skills in choosing materials for certain uses on the basis of their mechanical properties, whether those properties are to do with the ease of shaping the material or the effectiveness of that material in use. Occasionally the material was chosen simply because it was readily available. If we find that a particular material was always used for a certain job, it's reasonable to deduce that Man was exerting materials selection criteria through experience.  相似文献   

17.
When attempting to understand where domestic plants and animals were domesticated,it is essential to consider the geographic distribution of the wild ancestor.Many domestic taxa now inhabit just about every continent thanks to their human-mediated dispersal which began soon after they were incorporated into the human niche.But just because sheep are now crucial to the economy of New Zealand and Wales,for example,does not mean that they were domesticated there.In fact,they could not have been since the wild ancestors of sheep were geographically restricted to a relatively small portion of Western Eurasia (Pedrosa et al.,2005).  相似文献   

18.
Nature is a huge gallery of art involving nearly perfect structures and properties over the millions of years of development. Many plants and animals show water-repellent properties with fine micro-structures, such as lotus leaf, water skipper and wings of butterfly. Inspired by these special surfaces, the artificial superhydrophobic surfaces have attracted wide attention in both basic research and industrial applications. The wetting properties of superhydrophobic surfaces in nature are affected by the chemical compositions and the surface topographies. So it is possible to realize the biomimetic superhydrophobic surfaces by tuning their surface roughness and surface free energy correspondingly. This review briefly introduces the physical-chemical basis of superhydrophobic plant surfaces in nature to explain how the superhydrophobicity of plant surfaces can be applied to different biomimetic functional materials with relevance to technological applications. Then, three classical effects of natural surfaces are classified: lotus effect, salvinia effect, and petal effect, and the promising strategies to fabricate biomimetic su- perhydrophobic materials are highlighted. Finally, the prospects and challenges of this area in the future are proposed.  相似文献   

19.
Members belonging to the siderophilin family are iron-binding and iron-transporting proteins, which includes transferrin and lactoferrin. They have only been found in animals previously. If siderophilin could be found in and isolated from a plant, its production and subsequent extensive application could be increased. The present study is the first to report the discovery of a homolog of siderophilin in a plant. In order to purify antifreeze proteins from Ammopiptanthus mongolicus (Maxim.) Cheng f., the authors processed the proteins from the leaves using techniques such as column chromatography using DEAE-Cellulose-52, gel filtration via Sephacryl S-100 HR medium, hydrophobic interaction chromatography, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Mass spectroscopy was performed on the three proteins purified and the sequence of one of the proteins (containing 32 amino acids) was found to have 97% homology with the corresponding part of one type of human lactoferrin. Moreover, one of the two peptides belongs to an iron-binding domain. So, it is possible that siderophilin also exists in plants and plays a role as an antibacterial and antifungal, among other actions.  相似文献   

20.
After major natural disasters, such as the recent earthquake-tsunami event in South Asia, reports appear about the mysterious ability of animals to anticipate and to escape the impending danger. This is an opportunity to recall the long history of this phenomenon in the traditions of different civilizations, to evaluate Chinese efforts, 30-40 years ago, to use this phenomenon for earthquake prediction, and to judge its state of acceptance in modem science. An effort is made to introduce this phenomenon as a research field of modem bionics. The timing is favorable since, increasingly, infrared thermal anomalies, monitored from satellite, suggesting litho-atmospheric processes, are found to precede earthquakes. They were unexpected by seismologists and are here suggested to essentially reflect the energy conversion patterns responsible for the signals monitored by animals. The aim is to learn from animals in the long term how natural disasters can better be anticipated, and how simple technical warning systems can be developed. Some challenges are analyzed. One is interpretation of the nature of energy release prior to the main earthquake disaster resulting in "macro-anomaly" precursors, another is better to understand the effect on animal senses. The role of non-linear cooperative phenomena including tsunamitype waves is emphasized.  相似文献   

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