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鸟类鸣声地理变异的形成机制 总被引:1,自引:0,他引:1
鸣声在鸟类的通讯和性选择中具有重要的意义.鸣声地理变异广泛存在于鸟类中,对其研究有助于了解近缘种的分类和演化历史.鸣声地理变异格局的形成是一个复杂的过程,可能是某一因素起主导、多因素协同作用的结果.主要影响因素有奠基者效应、鸣声漂变、遗传差异、性选择、生境等.年际间鸣声的稳定性和种群内鸣声的变异性,是鸣声地理变异研究中应该重视的问题,通过鸣声学习和扩散机制来研究鸣声地理变异,可能是将来本领域的研究热点. 相似文献
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《生态学杂志》2016,(11)
生物多样性随纬度而变化是自然界的重要现象,而生物的性状差异是生物多样性最直接的体现。鸟类的羽色和鸣声在保卫领域、吸引配偶时起着重要作用,与物种形成和性选择联系密切。本文综述了鸟类羽色和鸣声演化速率随纬度变化的规律,探讨了影响其演化速率的因素。影响鸟类性状演化速率的因素包括近缘姊妹种的竞争、有效种群大小、繁殖期、世代周期等。分布区重叠的姊妹近缘物种的种间竞争和避免杂交的压力大,可促进性状的快速分化;小种群遗传漂变速度快,加快性状的演化;高纬度地区鸟类繁殖期短,性选择压力强,加剧性选择性状的演化;世代时间对性状演化的积累有决定性影响。基于美洲鸟类的研究,高纬度地区近缘种羽色和鸣声的演化更快。本文提出,在性状演化的研究中,需要充分考虑亲缘谱系的影响和解释变量的选择,并建议尝试从鸟类可感知的角度衡量性状的演化,关注羽色和鸣声的相互影响及其对性状演化速率的作用,增加对亚洲地区鸟类的研究。 相似文献
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被动声学监测通过分析鸟鸣声信息来实现物种识别,为鸟类多样性监测提供了一种切实可行的技术方案。由于鸟种的鸣声复杂多变,如何通过声纹快速准确辨别物种,分析鸟类丰度,降低对人工操作的需求等技术难题,成为基于声纹的鸟类多样性监测所面临的挑战。本文提出了基于音节聚类的鸟类鸣声监测框架:首先通过音高、频率平坦度等音频特征在声纹数据中提取音节,然后通过无监督表征学习与狄利克雷过程(Dirichlet process)混合模型对音节进行深度无监督聚类训练,完成音节聚类和自动音节种类推断。分析结果表明,本文提出的基于音节聚类的鸟类鸣声监测框架在处理开源数据集白腰文鸟(Lonchura striata)的曲目时可获得接近90%的聚类准确率。在此基础上,本研究对2022年4-5月在广州市白云山公园固定监测点所录制的10种鸟类鸣声进行了无监督的音节聚类分析,验证了本文所提出的基于音节聚类的鸟类鸣声监测框架的有效性:本技术不仅可以支持快速鸟类物种识别,还可以统计和分析不同物种鸟鸣在时间、频度、数量上的变化。这些结果表明,基于音节聚类的鸟类鸣声监测框架可以显著降低对人工标注训练数据的要求,克服传统鸟鸣物种识别框架... 相似文献
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扩散是生物个体之间相互远离的单线性运动,是生物的基本特征之一,对种群的分布、动态及遗传结构等方面均有重要影响.扩散有出生扩散和繁殖扩散等主要形式.动物发生扩散的主要原因包括:避免近亲繁殖、减少竞争、改变繁殖地点等.近年来,扩散已经成为鸟类学研究的前沿领域.评述了鸟类扩散行为的性别差异、体质对于扩散的影响,阐述了扩散的基本过程及栖息地选择、长距离扩散等内容,同时介绍了环志标记、无线电遥测、分子生物学等研究鸟类扩散的主要方法.展望了鸟类扩散研究的发展趋势,认为新技术和新方法的应用将成为扩散生态学家关注的重要问题,未来研究将更加重视对鸟类扩散理论问题的探讨,而对鸟类扩散行为的研究成果也会更广泛地应用于濒危物种及其栖息地的保护工作中. 相似文献
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声信号是鸟类交流的重要方式。鸟类的鸣声特征受到生境的塑造和性选择,也受到发声器官的影响,如种间的比较研究发现,体重大的鸟类鸣声频率低,喙短的鸟类鸣声频宽大。在种内是否也存在类似的规律,目前的结论还不一致。2012年6月,在北京小龙门地区(40°00'N,115°26'E)测量了17只灰眉岩鹀(Emberiza godlewskii)的形态参数以及鸣声的频率特征,未发现体重或喙长与鸣声的最高频率、最低频率、峰频或频宽存在显著的相关性。本研究的结果支持在小型雀形目鸟类中,体型对繁殖期鸣唱频率特征的影响不显著。 相似文献
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The physiological age of mother tubers (Solanum tuberosum L. cv. Kennebec) used as a source of material influenced kinetin-induced in vitro tuberisation. Tuberisation significantly
increased with physiological age. Kinetin- or ancymidol-induced tuberisation, plantlet and microtuber dry weight decreased
with increasing number of subcultures. Single-node segments obtained from tubers stored for more than 9.5 months at 4 °C showed
increased kinetin-induced tuberisation rates and earlier tuberisation than those obtained from younger tubers. For any physiological
age, material may be safely multiplied using node propagation until the third subculture and bioassayed for tuberisation without
variation in the response.
Received: 8 July 1996 / Revision received: 28 March 1998 / Accepted: 28 March 1998 相似文献
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超临界CO_2对面包酵母活性影响的研究 总被引:4,自引:1,他引:3
超临界CO2下面包酵母菌株的存活率,随菌体含水量的增加、在超临界CO2流体中停留时间的延长和压力的增大而逐渐降低;当CO2的降压速率为025MPamin时,酵母菌的存活率最高。结果表明,在超临界CO2条件下导致酵母菌死亡的主要原因是压力的快速变化与低pH值。 相似文献
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海藻多糖生物活性及分子修饰 总被引:15,自引:0,他引:15
简要介绍了近年来有关海藻多糖抗病毒、抗肿瘤、免疫促进、免疫抑制等生理活性的最新研究 ,重点介绍了不同种类海藻多糖的不同生理活性机理的研究进展。对多糖与生理活性之间的构效关系进行了阐述 ,在构效关系基础上进行多糖分子结构修饰是提高海藻多糖生理活性、降低毒副作用的有效手段。进一步介绍了目前多糖分子修饰常用方法 ,并对修饰后分子的生理活性改变进行了阐述。 相似文献
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The chemical form and physiological function of nickel in some Iberian Alyssum species 总被引:14,自引:0,他引:14
The form of nickel in leaves of Iberian subspecies of Alyssum serpyllifolium Desv. was investigated. Subsp. lusitanicum T. R. Dudley and P. Silva (from N.E. Portugal) and subsp. malacitanum Rivas Goday (from Southern Spain) were hyperaccumulators of nickel (>1000 μg/g Ni) whereas their non-accumulating precursor (subsp. serpyllifolium ) was not. Nickel existed mainly as a water-soluble polar complex in the vacuoles. Small concentrations of nickel did however exist in cell fractions, particularly in the mitochondria where enzyme systems are located. Gas-liquid chromatography on the purified nickel complexes showed that this element is associated principally with malic and malonic acids which are present in high concentrations in the hyperaccumulators but not in subsp. serpyllifolium . It is suggested that production of malic acid is a mechanism whereby hyperaccumulators can tolerate unfavourable edaphic factors such as nickel-rich soils. Presence of nickel in the mitochondria can presumably block the citric acid cycle by deactivating malic dehydrogenase leading to build-up of malic acid in the vacuoles which could then absorb excess nickel by a complexing reaction and lead to its diffusion back into the vacuoles from the mitochondria, hence unblocking the citric acid cycle. It is postulated that the chemical evidence suggests that the two hyperaccumulators are not conspecific and that subsp. malacitanum should be promoted to full specific rank. 相似文献
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B. A. Vanderkist T. D. Williams † D. F. Bertram †‡ L. W. Lougheed† J. L. Ryder† 《Functional ecology》2000,14(6):758-765
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Eun-Hye Jang Byoung-Jun Park Mi-Sook Park Sang-Hyeob Kim Jin-Hun Sohn 《Journal of physiological anthropology》2015,34(1)
Background
The aim of the study was to examine the differences of boredom, pain, and surprise. In addition to that, it was conducted to propose approaches for emotion recognition based on physiological signals.Methods
Three emotions, boredom, pain, and surprise, are induced through the presentation of emotional stimuli and electrocardiography (ECG), electrodermal activity (EDA), skin temperature (SKT), and photoplethysmography (PPG) as physiological signals are measured to collect a dataset from 217 participants when experiencing the emotions. Twenty-seven physiological features are extracted from the signals to classify the three emotions. The discriminant function analysis (DFA) as a statistical method, and five machine learning algorithms (linear discriminant analysis (LDA), classification and regression trees (CART), self-organizing map (SOM), Naïve Bayes algorithm, and support vector machine (SVM)) are used for classifying the emotions.Results
The result shows that the difference of physiological responses among emotions is significant in heart rate (HR), skin conductance level (SCL), skin conductance response (SCR), mean skin temperature (meanSKT), blood volume pulse (BVP), and pulse transit time (PTT), and the highest recognition accuracy of 84.7 % is obtained by using DFA.Conclusions
This study demonstrates the differences of boredom, pain, and surprise and the best emotion recognizer for the classification of the three emotions by using physiological signals. 相似文献20.
李佳 《现代生物医学进展》2012,12(12):2379-2381
宽恕作为人类所独有一种美德,对人们来说并不陌生,但对于宽恕的系统研究却仅始于上个世纪80、90年代。本文采用文献法着重从生理心理、神经证据等方面对宽恕认知神经科学方面的研究进行了梳理和整合,最后对该研究领域未来的发展方向进行了展望。 相似文献