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1.
本文给出了鸣鸣蝉调音肌(TMc)的结构及其与发声膜(SM)的连接关系,揭示了TMc的调音功能。 TMc的前、后支分别与SM前缘底面的外、内侧连接,有助于牵拉SM,其纵轴与SM的膜面约成120°角。理论上估计,TMc对SM的向下垂直拉力和沿膜面的向前水平拉力可能分别约为总拉力的87%和50%。 TMc具有重要的调音功能。不仅影响每侧SM产生的2个脉冲列(PT)的脉冲幅值,每个PT中第1和2脉冲幅值平均约下降3—10dB;而且影响SM发声过程的均一性。同时,对鸣声谱中第二陪音的峰值频率的幅值有明显的影响,其13600—13900Hz、15015—15100Hz和16756—17090Hz的幅值分别平均下降约5.9、8.4和16.3dB。  相似文献   

2.
给出了鸣鸣蝉发声肌肌原纤维的双阵结构,其肌纤维中并存两种不同阵列的“快”和“慢”劝肌原纤维不同,分别为3:1和5:1。明显区别于单音调鸣声的蝉类发声肌肌原纤维的RTTF为3:1的单阵列,即与鸣鸣蝉变音调声产生的原初机制相适应。  相似文献   

3.
给出了鸣鸣蝉发声肌肌原纤维的双阵列结构,其肌纤维中并存两种不同阵列的“快”和“慢”动肌原纤维(FSM和SSM).FSM和SSM虽然由粗肌丝构成相同的阵列骨架,但细肌丝对粗肌丝的比例(RTIF)不同,分别为3:1和5:1.明显区别于单音调鸣声的蝉类发声肌肌原纤维的RTIF为3:1的单阵列结构,即与鸣鸣蝉变音调声产生的原初机制相适应.  相似文献   

4.
本文由1741个叫声的分析,给出了蟋蟀的鸣声特征和黑蝉叫声的影响.雄蟋招引声的每个单次叫声(SC)平均含有7.6个节拍,每个含有2个脉冲列组,每组含有4个主要的调幅脉冲列.每个SC的声长、间隔和平均重复周期(?)及节拍速(?)分别为1.285-1.325s,0.755—0.746s和2.078s及每秒7.6个节拍.鸣声谱的主峰频率(MPF)和MPF下降20db的带宽分别为5223±79Hz和(4498±82)—(5656±68)Hz.正在歌唱的蟋蟀鸣声基本上不受黑蝉自鸣声的影响,但黑蝉的前置自鸣声对蟋蟀鸣声波形有一定的影响.黑蝉的惊叫声不仅对蟋蟀鸣声波形有明显影响,而且时间特性有一定影响,即(?)约缩短一半,(?)的变差明显扩大.但对频率特性都无影响.  相似文献   

5.
蚱蝉自鸣声的音色分为单音色、双音色.及三音色等.本文进一步阐明每种音色的变化及高幅值脉冲对主音色能量的影响.蚱蝉自鸣声音色的变化主要是指频谱主音色频率(MTF)的显著改变、蚱蝉单色自鸣声的MTF主要在4.1—5.8kHz的频带内变化,双音色自鸣声的主次音色频率有相互颠倒现象,MTF主要在3.6—5.4kHz之间,三音色自鸣声的MTF虽然在3.5—4.5kHz比较窄的频带内,但三个音色峰的能量十分接近显示了三种音色成分.同只蚱蝉自鸣声,在不同的鸣声段具有近似相等的最大幅值,但高幅值脉冲个数的多少不同,相应主音色能量的大小与这些脉冲个数的多少对应.  相似文献   

6.
蝉鸣特征及其在分类学上的意义:同翅目:蝉总科   总被引:9,自引:2,他引:9  
本文总结了蝉鸣的几种机制,并初步提出了具鼓膜发音器的蝉鸣模式图;综述了国内外有关蝉鸣在分类中的应用历史和现状;分析讨论了蝉鸣声在各级分类阶元中的差异和应用,即发音机制和方式可用于科及亚科级的分类;鸣声的颖谱特征和一些鸣叫行为可为属级分类提供一些依据,鸣叫节律型具有明显的种性,而音色的差异在近缘种,疑难种及其种下分类方面具有重要的意义。  相似文献   

7.
迷卡斗蟋鸣声的声学特征及其生物学意义   总被引:2,自引:0,他引:2  
首次利用计算机技术对迷卡斗蟋Velarifictorus micado (Saussure)的鸣声特征 及其生物学意义进行了研究。结果表明:迷卡斗蟋在不同性比条件下,鸣声的声学特征不同。雄性独处时发出召唤声;2只以上的雄性在一起时会发出警戒声、挑战声或胜利声;1雄1雌在一起时会发出欢迎声、求爱声,如果雌性不理会雄性的求爱时则会发出一种催促声。利用计算机 ,除了对人们用耳辨别的3种鸣声(召唤声、求偶声和争斗声)进行客观记录外,还可以对以前所称的“求偶声”和“争斗声”进行更细致地分析和比较。根据其生物学意义,作者首次将其 鸣声分为7种,并对这7种鸣声在功率谱和时域两方面进行了比较,发现迷卡斗蟋在不同行为下 有不同的鸣声特征,传递不同的信息。  相似文献   

8.
迷卡斗蟋鸣声的声学特征及其生物学意义   总被引:2,自引:0,他引:2  
首次利用计算机技术对迷卡斗蟋Velarifictorusmicado (Saussure)的鸣声特征及其生物学意义进行了研究。结果表明 :迷卡斗蟋在不同性比条件下 ,鸣声的声学特征不同。雄性独处时发出召唤声 ;2只以上的雄性在一起时会发出警戒声、挑战声或胜利声 ;1雄 1雌在一起时会发出欢迎声、求爱声 ,如果雌性不理会雄性的求爱时则会发出一种催促声。利用计算机 ,除了对人们用耳辨别的 3种鸣声 (召唤声、求偶声和争斗声 )进行客观记录外 ,还可以对以前所称的“求偶声”和“争斗声”进行更细致地分析和比较。根据其生物学意义 ,作者首次将其鸣声分为 7种 ,并对这 7种鸣声在功率谱和时域两方面进行了比较 ,发现迷卡斗蟋在不同行为下有不同的鸣声特征 ,传递不同的信息。  相似文献   

9.
10.
自然资源生态安全是国家安全的重要组成部分,自然资源生态安全区划对保障区域可持续发展提供了重要途径。基于自然资源数据、生态环境数据和相关区划资料,从生态敏感性与生态服务重要性角度构建了自然资源生态安全评价指标体系,进而揭示了中国自然资源生态安全的空间格局;通过建立区划的原则和指标,按照一级区主要反映自然资源空间分布格局,二级区主要揭示自然资源生态安全水平的差异,采用SOFM网络制订了中国自然资源生态安全区划方案。结果显示:(1)中国自然资源生态安全水平整体偏低,以中警与重警状态区域为主,安全和较安全状态的区域仅占24.22%,其中低安全等级区多分布于400mm等降水量线以西的干旱、半干旱区,高安全等级区则集中分布于水热资源与生物资源较为丰富的东南部地区;(2)中国自然资源生态安全区划方案包括8个一级区与27个二级区,总结归纳各大区自然资源的特征和威胁生态安全的问题,并针对二级区自然资源生态安全状况提出了对策建议。研究结果可为分区、分类推进全国自然资源可持续利用和国土空间优化提供理论支持与决策依据。  相似文献   

11.
The ground crickets Allonemobius fasciatus and A. socius meet in a mosaic zone of overlap and hybridization stretching from the East Coast to at least Illinois. To test whether male calling song differences were enhanced in sympatry, we analyzed the songs of crickets from inside and outside the zone of overlap along two transects. No evidence of calling song displacement was found in A. socius males from populations within the zone of overlap. On the other hand, A. fasciatus displayed calling song displacement in three populations. Our results are consistent with the hypothesis that the selective pressure exerted by the challenge from a related species is frequency dependent. While not a conclusive demonstration, the observed shifts in calling song are strongly suggestive of reproductive character displacement.  相似文献   

12.
黑蚱蝉(Cryptotympana atrata Fabricius)鸣声的波谱特征   总被引:2,自引:2,他引:0  
本文研究了双气囊黑蚱蝉的Click声、自鸣声和群鸣声.其鸣声波形兼有调幅与鸣声主频变化特征.1.Click声主峰频率分布在2.64—5.73KHz之间.2.自鸣声主峰频率在3.6—6KHz之间,比Click声的分布宽度略窄.3.群鸣声的主峰频率分布在4—7KHz范围内.  相似文献   

13.
白头鹎方言的初步研究   总被引:18,自引:0,他引:18  
姜仕仁  施青松 《动物学报》1996,42(4):361-367
对浙江省乘泗岛,普陀岛,温岭,长兴,杭州和龙游等6个地区白头鹎的鸣声进行了研究,发现它们鸣声主句的语调,音节数,持续时间,频谱特征和频率范围等均有差异,说明白头鹎鸣声中普遍存在“方言”,但它们作为同一个种在鸣声主句上有其共同特征:主要是鸣声多在1.5-3kHz的低中频段内变化,单音节的鸣叫声等都极为相似。  相似文献   

14.
Birdsong is a classic example of a learned trait with cultural inheritance, with selection acting on trait expression. To understand how song responds to selection, it is vital to determine the extent to which variation in song learning and neuroanatomy is attributable to genetic variation, environmental conditions, or their interactions. Using a partial cross fostering design with an experimental stressor, we quantified the heritability of song structure and key brain nuclei in the song control system of the zebra finch and the genotype‐by‐environment (G × E) interactions. Neuroanatomy and song structure both showed low levels of heritability and are unlikely to be under selection as indicators of genetic quality. HVC, in particular, was almost entirely under environmental control. G × E interaction was important for brain development and may provide a mechanism by which additive genetic variation is maintained, which in turn may promote sexual selection through female choice. Our study suggests that selection may act on the genes determining vocal learning, rather than directly on the underlying neuroanatomy, and emphasizes the fundamental importance of environmental conditions for vocal learning and neural development in songbirds.  相似文献   

15.
Songs of Darwin's finches were studied on the Galápagos Island of Daphne Major from 1976 to 1995. A single, structurally simple, and unvarying song is sung throughout life by each male of the two common species, Geospiza fortis (medium ground finch) and G. scandens (cactus finch). Songs of the two species differ strongly in quantitative features, and individual variation among males is much broader in G. fortis than in G. scandens. Although there are exceptions, songs of sons strongly resemble the songs of their fathers. They also resemble the songs of their paternal grandfathers, but not their maternal grandfathers, indicating that they are culturally inherited and not genetically inherited. Female G. fortis display a tendency to avoid mating with males that sing the same type of song as their father. They also avoid mating with males that sing heterospecific song, with very rare exceptions. Thus song, an evolving, culturally inherited trait, is an important factor in species recognition and mate choice. It constrains the mating of females to conspecifics, even when there is no genetic penalty to interbreeding, and thus may play a crucial role in species formation by promoting genetic isolation on secondary contact. The barrier is leaky in that occasional errors in song transmission result in misimprinting, which leads to a low incidence of hybridization and introgression. Introgression slows the rate of postzygotic isolation, but can produce individuals in novel genetic and morphological space that can provide the starting point of a new evolutionary trajectory.  相似文献   

16.
Inbreeding depression is thought to be a major factor affecting the evolution of mating systems and dispersal. While there is ample evidence for inbreeding depression in captivity, it has rarely been documented in natural populations. In this study, I examine data from a long-term demographic study of an insular population of song sparrows (Melospiza melodia) and present evidence for inbreeding depression. Forty-four percent of all matings on Mandarte Island, British Columbia, were among known relatives. Offspring of a full-sib mating (f = 0.25) experienced a reduction in annual survival rate of 17.5% on average. Over their lifetime, females with f = 0.25 produced 48% fewer young that reached independence from parental care. In contrast, male lifetime reproductive success was not affected by inbreeding. Reduced female lifetime reproductive success was mostly due to reduced hatching rates of the eggs of inbred females. Relatedness among the parents did not affect their reproductive success. Using data on survival from egg stage to breeding age, I estimated the average song sparrow egg on Mandarte Island to carry a minimum of 5.38 lethal equivalents (the number of deleterious genes whose cumulative effect is equivalent to one lethal); 2.88 of these lethal equivalents were expressed from egg stage to independence of parental care. This estimate is higher than most estimates reported for laboratory populations and lower than those reported for zoo populations. Hence, the costs of inbreeding in this population were substantial and slightly above those expected from laboratory studies. Variability in estimates of lethal equivalents among years showed that costs of inbreeding were not constant across years.  相似文献   

17.
云南景洪地区蝉鸣特点的分析   总被引:6,自引:1,他引:6  
蒋锦昌 《昆虫学报》1985,(3):257-265
本文对云南景洪地区三种蝉:A.周氏尖瓣蝉Acutivalva chotti Yao,B.大狭瓣蝉Aola bindusara Distant,C.中华舌瓣蝉Linguvalva sinensis Chou et Yao的鸣声特点,及其晨鸣进行了分析。 蝉A和蝉B的鸣声都是由主峰频率为6.3 kHz的单次声群(SSG)和连续声群(CSG)组成的节律声。但是蝉A鸣声的节律平均周期、SSG中单次声的个数和CSG中调幅脉冲列的重复频率等都明显地与蝉B有区别。蝉C的鸣声是由重复频率约120Hz的调幅脉冲列组成的连续声,其主峰频率为5kHz。 蝉B的傍晚鸣声与午间鸣声相比较,其CSG中调幅脉冲列的重复频率和主峰频率等都是相同的,仅仅是节律的平均周期延长1.7秒,1/3倍频谱中低于1,000Hz的各个频率幅值明显下降。 这三种蝉晨间群鸣由前奏、高潮声和尾声组成。高潮声开始于6点(28±2)分,尾声终止于6点(43±2)分,是以24小时为周期的生物钟现象。 这些结果可能为蝉科分类和蝉的声通讯研究提供某些参考。  相似文献   

18.
神农架豆科植物的分布及其区系特点   总被引:1,自引:0,他引:1  
神农架位于湖北西部,素有“华中第一峰”之称,最高海拔3105米。神农架有豆科植物31属56种(不包括栽培种),其中,乔木10种,灌木19种,草本22种和藤本5种。在温带常绿针叶林带内有2种生长,有28种分布在暖温性落叶阔叶和针叶混交林带,52种分布在亚热带落叶阔叶和常绿阔叶混交林带。其中,只有紫云英1种在三个带内都有分布,24种可跨两个分布带。在区系成分中,中国-日本成分16种,中国特有种21种,温带亚洲成分5种,欧亚成分4种,北温带成分3种,热带亚洲成分3种,热带亚洲和热带非洲成分1种,东亚-北美成分1种,西亚至东亚成分1种,中国-喜马拉雅成分1种。神农架豆科植物区系特点是:种类较丰富,成分复杂,特有种多,具明显的过渡特色。  相似文献   

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