Indirect and direct acoustic aggression in cicadas: first observations in the Palaearctic genus Tibicina Amyot (Hemiptera: Cicadomorpha: Cicadidae)

Tibicina Amyot is a cicada genus of the Palaearctic biogeographical region with seven taxa (species and subspecies) distributed in France. As in other cicadas, the sound production by tymbal vibration is restricted to males. In Tibicina, males are attracted by conspecific calling songs and tend to form groups of several individuals which maintain a minimal distance between each other. Observations based upon male–male interactions in such aggregations and on some preliminary experiments conducted with males kept in captivity revealed for the first time both indirect and direct aggression. Spacing and chorusing are interpreted as a by-product of indirect aggression mediated through the calling song. Direct aggression occurred when spacing is not respected. It is achieved through a ritualistic sequence that involves mainly the production of the rivalry song, an acoustic signal previously reported in the literature for two cicada species only. In addition, satellite males and male–male courting are reported. These preliminary results suggest that the sound social organization in the genus Tibicina is more elaborate than first suspected and should be reconsidered in terms of lek behaviour and sexual selection.     

曹操墓纠纷的理性思考——论我国考古论证制度的缺失和完善

曹操墓惊现河南安阳后,质疑纷起。＂挺曹派＂言之凿凿;＂反曹派＂学者认为证据不足,定性为时过早;公众质疑矛头直指政府和学术权威的公信力。各方法理辩论的背后折射出我国考古论证制度的不完善。     

Plasma sheet stretching accompanied by field aligned energetic ion fluxes observed by the NUADU instrument aboard TC-2

The NUADU (NeUtral Atom Detector Unit) instrument aboard TC-2 recorded 4л solid angle images of charged particles (E >180 keV) spiraling around the magnetic field lines in the near-Earth plasma sheet (at ~ -7 RE, equatorial dawn-to-night side) during a geomagnetic storm (Dst =-219 nT) on August 24, 2005. Energetic ion beam events characterized by symmetrical, ring-like, solid angle distributions around ambient magnetic field lines were observed during a 34-minute traversal of the plasma sheet by the TC-2 spacecraft. Also, observations during these multiple crossings of the plasma sheet were monitored by the magnetometer experiment (FGM) aboard the same spacecraft. During each crossing, a whistler-mode chorus enhancement was observed in the anisotropic area by the TC-2 low frequency electromagnetic wave detector (LFEW/TC-2) at a frequency just above that of the local lower hybrid wave. A comparison of the ion pitch angle distribution (PAD) map with the ambient magnetic field shows that an enhancement in the field aligned energetic ion flux was accompanied by tailward stretching of the magnetic field lines in the plasma sheet. In contrast, the perpendicular ion-flux enhancement was accompanied by a signature indicating the corresponding shrinkage of the magnetic field lines in the plasma sheet. Since both parallel ion-flux and perpendicular ion-flux enhancements occurred intermittently, the data were interpreted to imply a dynamical, oscillatory process of the magnetic field line (stretching and shrinking) in the near-Earth plasma sheet, which might have acted to help establish an interaction region in this area which would support continuous aurora-substorm triggering during the ongoing magnetic storm. The whistler-mode chorus may have been produced due to ion gyro-resonance during particle pitch angle diffusion after the plasma sheet compression.     

哨声模合声波驱动同步轨道高能电子通量上升的事例分析

采用LANL同步轨道卫星和ClusterC4卫星的数据,研究了2004年9月13日和2001年10月21日两个磁暴事件期间,辐射带同步轨道附近高能电子通量的变化和哨声模合声波的活动之间的关系．通过观测对比发现,在相同的空间位置,两个事件均观测到高能电子通量的上升和明显的合声波对磁场的扰动;而且高能电子通量上升的程度与合...     

源深流漫 百川汇融——从多重文化视角看中国传统多声歌唱艺术的传承与发展

远古的"大混唱"和先秦的"和声而歌"等群体歌唱活动体现了多声特点;汉唐以来进一步形成了和歌的多重旋律与节奏变化、"一倡众和"、即兴发挥的特征;宋元以来戏曲音乐中的多声歌唱延续了"即兴"特征.受西方文化中心论影响,中国传统多声歌唱艺术过去被视为陈旧与落后的象征,如今却因各民族传统艺术的不同特点、文化品格和学术价值等,日趋受到国际学术界的关注,譬如全国青歌赛中原生态、组合唱法的出现,对这一珍贵文化遗产的保护、传承和弘扬具有重要意义.从多重视角探讨传统多声歌唱艺术的传承轨迹与特点,对挖掘传统音乐资源、凸现中国音乐民族特征和个性价值具有深远意义.     

论“轻声高位”唱法在合唱表演中的运用

合唱艺术是一种群体声乐演唱艺术形式,要遵循"轻声高位"的发声要求。掌握轻声唱法是每一个合唱团队和训练者必须面临的首要问题。本文以合唱声音训练的基本方法为立足点,着重阐述了"轻声高位"唱法的训练要点和主要内容。     

Reproductive biology of Scinax fuscomarginatus (Anura,Hylidae) in south‐eastern Brazil

The present study describes the reproductive biology of Scinax fuscomarginatus in a remnant of Cerrado in south‐eastern Brazil. Observations were made between September 2002 and March 2004 at Estação Ecológica de Itirapina, State of São Paulo, south‐eastern Brazil. Breeding activities occurred in lentic and temporary bodies of water during the rainy season. Scinax fuscomarginatus exhibited a prolonged breeding pattern and a lek mating system. Males were smaller than females and defended individual calling areas through acoustic and physical interactions. Resident males consistently won encounters, but did not differ in size or mass from intruder males. Satellite behaviour was observed, but no female or amplected pair interception was registered. Scinax fuscomarginatus exhibited low operational sex ratios and the general reproductive mode in which eggs are laid in the water and tadpoles are aquatic. Amplexus was axillary and the eggs were deposited at the bottom of temporary ponds. Details on oocytes, egg masses, and eggs are included.     

<九歌>无对唱说

屈原《九歌》，近人多以为其中有对唱。《九歌》中到底哪些篇是对唱，哪些篇是独唱；哪些诗句是男唱，哪些诗句是女唱；哪些诗句是巫唱，哪些诗句是神唱；对唱是巫与神的对唱，还是神与神的对唱，抑或是主巫与群巫的对唱；各家都根据自己的理解而定，纯粹“以意为之”，没有什么客观标准。事实上，《九歌》本是祭歌。祭歌中所反映的全部乐神活动，都是由巫师执司其事的。巫师在祭祀鬼神时、一身二任，既代表他(她)自己，又装神弄鬼．诡称鬼神已经附体，代表着鬼神。同样的，巫师所唱的祭歌，则时而以巫师的口吻唱，时而又以鬼神的口吻唱，但都出自巫师一人之口。作为祭歌的《九歌》，正是巫师的独唱或合唱(独唱者一人而兼神、巫两种角色)，而不是男与女、神与巫或主巫与群巫的对唱。     

如何做好合唱指挥前的案头工作

合唱 ,是声乐艺术中的整体表现形式 .它是通过作曲家、合唱队员和指挥之间的相互配合而共同完成的 .其中指挥是作曲家与合唱队员及听众之间的桥梁 ,它通过各种指挥语言 ,组织指导合唱队揭示音乐作品的主题思想 ,表现音乐的情感内涵 .以《黄河船夫曲》为例 ,从作品的选择、了解、分析、处理及指挥动作的设计五个方面论述了指挥在排练之前 ,该如何认真、细致地做好案头工作 .