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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Estudo da História Natural do Grilo Cavernícola Strinatia Brevipennis (Ensifera: Phalangopsidae) em Laboratório / Natural History of Cave Cricket Strinatia brevipennis (Ensifera: Phalangopsidae) in Laboratory

Franco, Flavia Pellegatti 13 February 1998 (has links)
Este estudo foi realizado em laboratório entre fevereiro de 1995 e dezembro de 1997. Os grilos (Strinatia brevipennis) foram coletados de diversas cavernas do Parque Estadual Intervales, no Vale do Ribeira, SP, e mantidos no porão do Edifício Ernesto Marcus, Departamento de Zoologia do IBUSP para estudo da história natural da espécie. Outra espécie de grilos (Endecous itatibensis) foi acompanhada devido a uma coleta acidental da mesma. As duas espécies foram mantidas separadamente, uma vez que a primeira não sobrevive em contato com a segunda. A reprodução de S. brevipennis ocorreu com sucesso em caixas de isopor, principalmente no verão. A reprodução de E. itatibensis, por outro lado, ocorreu apenas entre indivíduos mantidos livremente na câmara de criação, onde observou-se grande sucesso reprodutivo, com várias gerações e uma grande população proveniente de apenas uma fêmea. O período embrionário médio de S. brevipennis foi de 56 dias. O desenvolvimento pós-embrionário também foi acompanhado, onde observou-se provável variação no número de mudas (10 ou 11) antes de tornarem-se adultos. A identificação de macho e fêmea é facilmente observada nos três últimos instares ninfais e nos adultos através do surgimento do ovipositor (para ambas espécies) nas fêmeas, e das tégminas no último instar ninfal para S. brevipennis e no penúltimo para E. itatibensis nos machos. As fêmeas são ápteras nas duas espécies estudadas. A caracterização morfométrica mostra que os primeiros estágios da vida podem se confundir quanto às dimensões corporais para S. brevipennis. Nos últimos instares e adultos a caracterização torna-se mais facilitada através das medidas do comprimento do fêmur e da tíbia da perna III, e dos dimorfismos sexuais. / This study was conduced in laboratory between February 1995 and December 1997. The crickets (Strinatia brevipennis) have been collected in several caves from Parque Estadual Intervales, Ribeira Valley, São Paulo state. They were kapt in a room in the basement of Edifício Ernesto Marcus, Departamento de Aoologia IBUSP, to develop a study focusing their natural history. Another species of crickets (Endecous itatibensis) was studied due to an accidental collection. The two species were maintained in different compartments because the first did not survive whem in direct contact with the second. Reproduction of S. brevipennis was successful inside boxes, mainly during summer. Reproduction of E. itatibensis was only successful when animals were kept freely inside the compartment, where a large reproductive success for several generations was originated from a single female. S. brevipennis showed a mean period of embryonic development of 56 days. Post-embryonic development showed a variation of 10-11 molting events to achieve adulthood. Telling males from females is an easy task during the last three nymphal stages and among adults because of the development of ovipositor among females of both species; and development of mesothoracic wings during the last nymphal stage os S. brevipennis or the penultimate nymphal stage of E. itatibensis among males. Females are wingless in both species. Morphometric characterization showed that the first nymphal stages are hardly told from each other. Last stages and adults can be distinguished both from sexual dimorphisms and length of femur and tibia of leg III.
2

Estudo da História Natural do Grilo Cavernícola Strinatia Brevipennis (Ensifera: Phalangopsidae) em Laboratório / Natural History of Cave Cricket Strinatia brevipennis (Ensifera: Phalangopsidae) in Laboratory

Flavia Pellegatti Franco 13 February 1998 (has links)
Este estudo foi realizado em laboratório entre fevereiro de 1995 e dezembro de 1997. Os grilos (Strinatia brevipennis) foram coletados de diversas cavernas do Parque Estadual Intervales, no Vale do Ribeira, SP, e mantidos no porão do Edifício Ernesto Marcus, Departamento de Zoologia do IBUSP para estudo da história natural da espécie. Outra espécie de grilos (Endecous itatibensis) foi acompanhada devido a uma coleta acidental da mesma. As duas espécies foram mantidas separadamente, uma vez que a primeira não sobrevive em contato com a segunda. A reprodução de S. brevipennis ocorreu com sucesso em caixas de isopor, principalmente no verão. A reprodução de E. itatibensis, por outro lado, ocorreu apenas entre indivíduos mantidos livremente na câmara de criação, onde observou-se grande sucesso reprodutivo, com várias gerações e uma grande população proveniente de apenas uma fêmea. O período embrionário médio de S. brevipennis foi de 56 dias. O desenvolvimento pós-embrionário também foi acompanhado, onde observou-se provável variação no número de mudas (10 ou 11) antes de tornarem-se adultos. A identificação de macho e fêmea é facilmente observada nos três últimos instares ninfais e nos adultos através do surgimento do ovipositor (para ambas espécies) nas fêmeas, e das tégminas no último instar ninfal para S. brevipennis e no penúltimo para E. itatibensis nos machos. As fêmeas são ápteras nas duas espécies estudadas. A caracterização morfométrica mostra que os primeiros estágios da vida podem se confundir quanto às dimensões corporais para S. brevipennis. Nos últimos instares e adultos a caracterização torna-se mais facilitada através das medidas do comprimento do fêmur e da tíbia da perna III, e dos dimorfismos sexuais. / This study was conduced in laboratory between February 1995 and December 1997. The crickets (Strinatia brevipennis) have been collected in several caves from Parque Estadual Intervales, Ribeira Valley, São Paulo state. They were kapt in a room in the basement of Edifício Ernesto Marcus, Departamento de Aoologia IBUSP, to develop a study focusing their natural history. Another species of crickets (Endecous itatibensis) was studied due to an accidental collection. The two species were maintained in different compartments because the first did not survive whem in direct contact with the second. Reproduction of S. brevipennis was successful inside boxes, mainly during summer. Reproduction of E. itatibensis was only successful when animals were kept freely inside the compartment, where a large reproductive success for several generations was originated from a single female. S. brevipennis showed a mean period of embryonic development of 56 days. Post-embryonic development showed a variation of 10-11 molting events to achieve adulthood. Telling males from females is an easy task during the last three nymphal stages and among adults because of the development of ovipositor among females of both species; and development of mesothoracic wings during the last nymphal stage os S. brevipennis or the penultimate nymphal stage of E. itatibensis among males. Females are wingless in both species. Morphometric characterization showed that the first nymphal stages are hardly told from each other. Last stages and adults can be distinguished both from sexual dimorphisms and length of femur and tibia of leg III.
3

Taxonomia das espécies de Lutosa Walker, 1869 das florestas do leste do Estado de São Paulo, Brasil: taxonomia, morfologia externa e do complexo fálico (Orthoptera, Stenopelmatoidea, Anostostomatidae)

Morselli, João Paulo [UNESP] 21 February 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-21Bitstream added on 2014-06-13T20:20:34Z : No. of bitstreams: 1 morselli_jp_me_botib.pdf: 6036306 bytes, checksum: a1d3b81b03b0a6291da447d8dae4d178 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O presente trabalho teve por objetivo estudar, do ponto de vista taxonômico, as espécies de Lutosa Walker, 1869 (Orthoptera, Ensifera, Stenopelmatoidea, Anostostomatidae) que ocorrem nas florestas do leste do Estado de São Paulo, Brasil, abrangendo análises da morfologia corporal externa, do complexo fálico e espermateca. Além da re-descrição do gênero e de três espécies já conhecidas, treze novas foram descritas e uma chave dicotômica de identificação é proposta para todas as espécies examinadas. Com base na estrutura de certos elementos que compõem o complexo fálico, dois grupos de espécies foram reconhecidos e definidos. Ainda no que concerne à morfologia da genitália masculina, uma proposta de terminologia para as diferentes áreas do apódema epifálico é apresentada. Dados preliminares sobre hábitos, ecologia e comportamento de espécies de Lutosa são fornecidos. / The aim of the present work was to study, from a taxonomic perspective, the species of Lutosa Walker, 1869 (Orthoptera, Ensifera, Stenopelmatoidea, Anostostomatidae) from the eastern forests from the State of São Paulo, Brazil, including analyses of external body morphology, phallic complex and spermatheca. Besides re-describing the genus and three of its valid species, thirteen new ones were described, and a dichotomic identification key for all examined species is presented. Based on the structure of certain elements that comprise the phallic complex, two species groups were recognized and defined. Still regarding male genital morphology, a terminological proposal for the different areas of the epiphallic apodeme is presented. Preliminary data on habits, ecology, and behavior of Lutosa species are given.
4

Long-term development of different grassland insect communities in Central Europe since the 1950s / Langfristige Entwicklung verschiedener Insektengemeinschaften der Grasflächen Mitteleuropas seit den 1950er Jahren

Schuch, Sebastian 14 July 2011 (has links)
No description available.
5

Acoustic profiling of the landscape

Grant, Paul Brian Charles 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Soft, serene insect songs add an intrinsic aesthetic value to the landscape. Yet these songs also have an important biological relevance. Acoustic signals across the landscape carry a multitude of localized information allowing organisms to communicate invisibly within their environment. Ensifera are cryptic participants of nocturnal soundscapes, contributing to ambient acoustics through their diverse range of proclamation songs. Although not without inherent risks and constraints, the single most important function of signalling is sexual advertising and pair formation. In order for acoustic communication to be effective, signals must maintain their encoded information so as to lead to positive phonotaxis in the receiver towards the emitter. In any given environment, communication is constrained by various local abiotic and biotic factors, resulting in Ensifera utilizing acoustic niches, shifting species songs spectrally, spatially and temporally for their optimal propagation in the environment. Besides the importance of Ensifera songs from an ethological point of view, the multitude of species-specific signals provide an acoustic tapestry representing species diversity across ecological gradients and over time. Acoustic inventorying and monitoring of the landscape can reflect the environmental status of ecological systems, from natural to disturbed by human influence. In contrast to traditional survey techniques, sound recording and interpretation is a non-invasive method that allows for the detection and classification of highly cryptic, yet insightful indicators of ecosystem change. Here, acoustic monitoring was used across diverse ecological gradients to improve understanding of species diversity patterns, and how they change in response to both natural gradients and in response to the human dominated landscape mosaic. This study was undertaken in three geographic locations from tropical rain forest of Brunei, Borneo, to the landscapemosaic of plantation forestry in KwaZulu-Natal, South Africa, and to the botanically rich, mountain fynbos region of the Cape Floristic Region, also in South Africa. Each region provided a diverse and particular landscape to test the value of acoustic surveys for determining local diversity patterns across natural gradients and to assess the value of the technique for assessing the impact human influence across landscapes. In tropical rainforests, an entire acoustic guild was investigated to determine how acoustic species partition their acoustic communication channels spectrally, temporally and spatially, to avoid acoustic interference. The overall assemblage showed considerable spectral partitioning. Diurnally active species showed low temporal niche overlap, whereas nocturnal species did not utilize temporal partitioning. Lack of nocturnal temporal partitioning suggests other mechanisms of acoustic avoidance are sufficient to avoid acoustic overlap, or that there are insufficient cues to partition nocturnal acoustic environments. Acoustic species also utilized spatial partitioning, with distinct acoustic assemblages at vertical heights and with elevation. Utilization of a range of different strategies allow many species to communicate with conspecifics with little or no interference from other species in a signal rich environment. Acoustic profiling was also undertaken in KwaZulu-Natal, South Africa, across a plantation forestry landscape mosaic with diverse ecological gradients containing both alien and indigenous vegetation, as well as boarding large natural protected areas. Areas covered in alien timber or non-endemic grass were devoid of acoustic signals. Managed areas that were mowed and heavily grazed were not effective in maintaining the natural complement of nocturnal acoustic species. Within natural vegetation patches inside plantations, acoustic species richness increased with plant heterogeneity and patch size. Patches of indigenous vegetation within the plantation matrix effectively reduced the contrast of transformed landscapes with surrounding natural areas, with indigenous forest patches containing a highly characteristic acoustic species assemblage. Within the botanically rich, mountain fynbos region of the Cape Floristic Region, acoustic profiling was conducted across gradients of elevation, season and vegetation. Across these gradients, katydid acoustic signals were identified and characterized for the first time. This resulted in the discovery of two new katydid species and a novel sound producing structure in a carabid beetle, a species previously unknown to produce sound. Acoustic diversity across seasonal and elevational gradients increased with increasing temperatures. Climatic variability along the elevational gradient produced variation in seasonal phenology. Katydids also utilized high frequency acoustic signals, which is probably an adaptation to overcome background noise from wind, so prevalent in this area. Furthermore, despite producing conspicuous signals for mate attraction and pair formation, katydids were found not to be part of bat-eared fox diet, an insectivorous, nocturnal predator that uses its characteristic large ears to detect sounds made by invertebrate prey. This study shows the value of using acoustic emissions from katydids to identify acoustic diversity patterns across ecological gradients and in response to human impacts on the landscape. / AFRIKAANSE OPSOMMING: Sagte, rustige insekliedjies voeg ‘n intrinsieke estetiese waarde aan die landskap. Tog is hierdie liedjies ook van belangrike biologiese waarde. Akoestiese seine oor die landskap dra ‘n magdom plaaslike inligting wat organismes in staat stel om onsigbaar te kommunikeer binne hul omgewing. Langhoringsprinkane is kriptiese deelnemers van die nagtelike klankomgewing en dra by tot die omringende akoestiek deur hul verskeidenheid van proklamasieliedjies. Alhoewel dit nie sonder inherente risiko’s en beperkings is nie, is die belangrikste funksie van seine seksuele advertering en paarvorming. Vir akoestiese kommunikasie om effektief te wees, moet seine hul geënkodeerde inligting handhaaf, sodat dit sal lei tot positiewe fonotaksis in die ontvanger teenoor die emittor. In enige gegewe omgewing, word kommunikasie beperk deur verskeie plaaslike abiotiese en biotiese faktore. Dit lei tot die gebruik van akoestiese nisse deur langhoringsprinkane, wat hulle liedjies spektraal, ruimtelik en temporeel aanpas vir optimale verspreiding in die omgewing. Benewens die belang van die langhoringsprinkaan liedjies uit ʼn etologiese oogpunt, bied die menigte spesie-spesifieke seine ʼn akoestiese tapisserie wat spesiesdiversiteit verteenwoordig oor ekologiese gradiënte en oor tyd. Akoestiese opname en monitering van die landskap kan die omgewingstoestand van ekologiese stelsels weerspieël, van natuurlike tot menslik versteurde stelsels. In teenstelling met tradisionele opnametegnieke, is klankopname en interpretasie ʼn nie-indringende metode wat dit moontlik maak om hoogs kriptiese, nog insiggewende indikators van ekosisteemverandering op te spoor en te klassifiseer. In hierdie studie is akoestiese monitering gebruik oor diverse ekologiese gradiënte om ons begrip te verbeter van spesies diversiteitspatrone, en hoe dit verander in reaksie op beide natuurlike gradiënte en in reaksie op die menslik gedomineerde landskapmosaïek. Hierdie studie is onderneem in drie geografiese liggings: tropiese reënwoud in Brunei, Borneo, die landskapmosaïek van plantasiebosbou in KwaZulu-Natal, Suid-Afrika, en die plantryke, bergfynbos-streek van die Kaap Floristiese Streek, ook in Suid-Afrika. Elke streek het 'n diverse en besondere landskap verskaf om die waarde van akoestiese opnames te toets vir die bepaling van plaaslike diversiteitspatrone in natuurlike gradiënte, asook om die waarde van die tegniek te bepaal vir die beoordeling van die impak van menslike invloed oor landskappe. In tropiese reënwoude, is 'n hele akoestiese gilde ondersoek om te bepaal hoe akoestiese spesies hul akoestiese kommunikasiekanale spektraal, ruimtelik en temporeel verdeel om akoestiese inmenging te vermy. Die algehele groep het aansienlike spektrale verdeling getoon. Dagaktiewe spesies het lae temporele nisoorvleueling getoon, terwyl nagtelike spesie nie temporele verdeling benut het nie. Gebrek aan nagtelike temporele verdeling dui daarop dat ander meganismes van akoestiese vermyding voldoende is om akoestiese oorvleueling te vermy, of dat daar onvoldoende seine is om nagtelike akoestiese omgewings te verdeel. Akoestiese spesies het ook ruimtelike verdeling benut, met verskillende akoestiese spesiesversamelings op vertikale hoogtes en met hoogte bo seevlak. Die gebruik van 'n verskeidenheid van strategieë maak dit moontlik vir spesies om te kommunikeer met min of geen inmenging van ander spesies in 'n seinryke omgewing. Akoestiese profielsamestelling is ook onderneem in KwaZulu-Natal, Suid-Afrika, oor 'n plantasiebosbou landskapmosaïek met diverse ekologiese gradiënte wat beide uitheemse en inheemse plantegroei, sowel as groot, natuurlike, beskermde gebiede ingesluit het. Gebiede wat bestaan het uit uitheemse timmerhoutbome of nie-endemiese gras, was heeltemal sonder akoestiese seine. Bestuursgebiede wat gesny en swaar bewei was, het nie doeltreffend die natuurlike komplement van nagtelike akoestiese spesies gehandhaaf nie. In natuurlike plantegroei fragmente binne plantasies, het akoestiese spesiesrykheid toegeneem met plantverskeidenheid en fragmentgrootte. Fragmente van inheemse plantegroei binne die plantasiematriks het effektief die kontras van getransformeerde landskappe met omliggende natuurlike gebiede verminder, en inheemse woudefragmente het hoogs kenmerkende akoestiese spesiesversamelings gehad. Binne die plantryke bergfynbosstreek van die Kaap Floristiese Streek, was akoestiese profielsamestelling gedoen oor gradiënte van hoogte bo seevlak, seisoen en plantegroei. Oor hierdie gradiënte, is langhoringsprinkaan akoestiese seine geïdentifiseer en gekenmerk vir die eerste keer. Dit het gelei tot die ontdekking van twee nuwe langhoringsprinkaan spesies en 'n nuwe klankvervaardiging struktuur in 'n Carabid kewer, 'n spesie wat nie voorheen bekend was om klank te produseer nie. Akoestiese diversiteit oor gradiënte van seisoen en hoogte bo seevlak het toegeneem met toenemende temperature. Variasie in klimaatstoestande oor die gradiënt van hoogte bo seevlak het variasie in seisoenale fenologie veroorsaak. Langhoringsprinkane het ook hoë frekwensie akoestiese seine benut, wat waarskynlik 'n aanpassing is om agtergrondgeraas van die wind, wat so algemeen is in hierdie gebied, te bowe te kom. Verder, ten spyte van die vervaardiging van opvallende seine vir maataantrekking en paarvorming, het langhoringsprinkane nie deel gevorm van die bakoorjakkals se dieet nie. Hierdie is 'n insekvretende, nagtelike roofdier wat gebruik maak van sy kenmerkende groot ore om klanke op te spoor wat gemaak word deur invertebraatprooi. Hierdie studie toon die waarde van die gebruik van akoestiese seine van langhoringsprinkane om akoestiese diversiteitspatrone te identifiseer oor ekologiese gradiënte en in reaksie op menslike impakte op die landskap.
6

Evolution of the Orthoptera: systematic placement among insects, internal phylogeny and the origin of bioacoustics

Leubner, Fanny 07 July 2017 (has links)
No description available.
7

Habitat Acoustics And Microhabitat Selection In An Ensiferan Assemblage Of A Tropical Evergreen Forest │

Jain, Manjari 11 1900 (has links) (PDF)
Several animals, both vertebrate and invertebrate, communicate using sound and they do so in a non-ideal medium, the habitat in which they live. As acoustic signals pass through the habitat, they suffer loss of information due to signal degradation, which is often determined by the acoustic properties of the habitat. Understanding the influence of habitat-induced constraints on signaling is vital to the understanding of evolution of signal structure. Over time signals can evolve their temporal and/or spectral characteristics so as to resist or reduce degradation. Conversely, signalers may modify their behaviour so as to improve transmission for effective communication. The Acoustic Adaptation Hypothesis (AAH) predicts that given the properties of the habitat in which animals communicate, signals should evolve so as to maximize their broadcast range and the number of potential receivers. The prediction of the hypothesis is that signal transmission is best in the native habitat as compared to non-native habitats. Since its inception, the idea of acoustic adaptation has been tested in several vertebrate species including birds, mammals and frogs but rarely in invertebrates. Moreover, most of these studies have been carried out at the macrohabitat level, such as transmission in forests versus grasslands. For animals with limited mobility such as invertebrates, a finer level of investigation at the microhabitat level is more relevant. Only one study on cicadas has investigated the predictions of the AAH at the microhabitat level. Besides, investigations done at the community level are largely missing in the literature. The effect of height on signal transmission is well documented, however, only one study on birds has investigated the AAH with respect to vertical stratification of coexisting species. Among invertebrates, crickets are well known for their calling songs which males use to attract conspecific females over long distances. No study so far has tested the prediction of the AAH in these acoustically communicating invertebrates. The central focus of this study was to test the predictions of the AAH in a natural assemblage of ensiferan (cricket) species. I examined the prediction of the hypothesis at the microhabitat level with respect to the vertical stratification of co-existing ensiferan species. The study was carried out on an assemblage of crickets in the wet evergreen forests of Kudremukh National Park in the Western Ghats in Southern India. For this purpose, it was important to examine calling height and microhabitat selection in these animals because if the use of calling height and microhabitat was random, then there would not be any native height/microhabitat and the question of acoustic adaption would not arise. Therefore, I first standardized methods to characterize the habitat of the crickets. Using resource selection functions, I then quantified microhabitat selection in 13 ensiferan species. I also examined the calling heights of these species. My results suggest that these species are microhabitat specialists and also distribute vertically within the forest with respect to calling height. Based on the knowledge of the vertical distribution of these animals in the forest I then carried out playback experiments using natural calls of 12 species of Ensifera in their natural habitat. The transmission experiments were carried out at five heights in the forest, including the ground, different parts of the understorey as well as in the canopy. The study aimed to examine whether vertical stratification in the ensiferan species of Kudremukh is driven by selection for maximizing transmission range. I examined the effect of different heights on signal degradation. The investigation was carried out with respect to three different measures of signal degradation, namely, total attenuation, signal to noise ratio as well as envelope distortion. The results indicate a lack of overall support for the AAH with respect to vertical stratification of crickets in Kudremukh. However, a strong, independent effect of height of calling on signal degradation was found, with the ground being the worst layer for transmission and the mid-understorey (2 m) emerging to be good for all species with respect to all three measures of signal degradation. I then analysed the transmission data from a different point of view, exploring the possibility of evolution of signal structures that may confer some advantages in terms of signal transmission, given the habitat-induced constrains on signal propagation. The idea was to examine why certain species perform better than others in terms of signal transmission. This investigation was aimed at characterizing the effect of call features on signal attenuation. I found that temporal features of calls did not have a strong effect on height-specific signal attenuation. While call duration had no effect on signal attenuation, duty cycle did influence attenuation profiles of the calls, with high duty cycle calls performing better than low duty cycle calls. However, there was no interaction of height with the temporal features of calls, eliminating the possibility of these features being shaped by microhabitat or height dependent transmission characteristics. Spectral features of calls, on the other hand, affected signal attenuation very strongly. As expected, low frequency calls performed better than high frequency calls and pure tone calls fared much better than the broadband calls, especially on the ground and the canopy. To the best of my knowledge, this is the first study to carry out a rigorous quantification of microhabitat selection in Ensifera. This is also the first detailed examination of the Acoustic Adaptation Hypothesis at the microhabitat level, tested in a natural assemblage of coexisting invertebrate species.

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