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Bradley, Lucy, and Roberta Gibson. "Cricket Management." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/144782.
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2 pp.Indian house crickets and field crickets are the two most common crickets in Arizona. Although these crickets do not bite or carry diseases, they are considered a nuisance because of their "chirping". This publication focuses on common crickets found in Arizona, including the Indian house crickets, field crickets, and Jerusalem crickets. It also discusses the problems they cause and the strategies to control them.
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Ivy, Tracie Marie Sakaluk Scott Kitchener. "The evolution of polyandry in the decorated cricket, Gryllodes sigillatus." Normal, Ill. : Illinois State University, 2005. http://proquest.umi.com/pqdweb?index=0&did=1221741601&SrchMode=1&sid=4&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1176386432&clientId=43838.
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Thesis (Ph. D.)--Illinois State University, 2005.Title from title page screen, viewed April 12, 2007. Dissertation Committee: Scott K. Sakaluk (chair), Diane L. Byers, Steven A. Juliano, Sabine S. Loew, William L. Perry. Includes bibliographical references (leaves 96-114) and abstract. Also available in print.
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Lien, Kathryn. "Of the Crickets." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5435.
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Of the Crickets imagines the overlapping worlds of ethical ecological solutions to climate changed sustenance and the potential for collective excellence in female exclusive environments. Using garments, furniture, site-specific installation and directed performance, the project harnesses social and material sensitivity to mine solutions for idealized living.
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Ferreira, Marna. "Evolutionary implications of variation in the calling song of the cricket Gryllus bimaculatus De Geer (Ortohptera: Gryllidae." Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-03232007-132848.
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Gabel, Eileen. "Decision making in field crickets." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17643.
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Akustische Signale dienen vielen Tierarten als Mittel zur Partnerfindung. Diese Tiere müssen ihre Entscheidung für den besten Paarungspartner durch die Integration der Parameter verfügbarer Signale treffen. Das Wahlverhalten weiblicher Grillen basiert auf der Attraktivität des zeitlichen Musters des männlichen Gesangs und auf dessen Intensität. Diese Eigenschaften korrelieren nicht zwangsweise positiv, daher wird sich kein Männchen in einer Aggregation von singenden Männchen als überragend abheben und somit wird dem Weibchen die Entscheidung erschwert. Die vorliegende Arbeit beschäftigt sich mit der Frage wie die relevanten Merkmale des männlichen Gesangs während der Entscheidungsfindung des Weibchens integriert werden. 6 Arten von Feldgrillen wurden in nicht-Wahl- und Wahlexperimenten hinsichtlich ihrer Antworten und Präferenzen für männliche Signale, welche sich in Pulsrate, Modulationstiefe, Intensität, Anordnung der Chirps während der Wiedergabe und der zeitlichen Verschiebung zweier Signale zueinander unterschieden, getestet. Des Weiteren wurde durch Transitivitätstests untersucht, ob dem Wahlverhalten weiblicher Grillen rationale oder vergleichende Entscheidungsmechanismen zugrunde liegen. Zusammenfassend zeigen die Ergebnisse, dass die Verarbeitungsmechanismen, welche der Entscheidungsfindung bei weiblichen Feldgrillen zugrunde liegen, in den untersuchten Arten ähnlich sind. Die Lokalisierung des Signals ist nicht unabhängig von der Erkennung. Neben einem generellen Verarbeitungsschema wurden zwischen den einzelnen untersuchten Arten charakteristische Unterschiede in der Mustererkennung, der Verarbeitung der Signalintensität und der Intensitätsgewichtung festgestellt. Jedoch wiesen nah verwandte Arten ähnlichere Präferenzen auf, als nicht nah verwandte Arten. Die Tests zur Transitivität der Präferenzen weisen auf vergleichende Entscheidungs-mechanismen hin und widersprechen einer rationalen Partnerwahl.In many animals acoustic signals serve for mate attraction. They thus need to make a decision about which is the best mating partner in a choice situation by integrating the cues of the available signals. Choice behaviour in female crickets is based on the attractiveness of the temporal pattern of a male’s calling song and on its intensity. The parameters of a calling song are not necessarily positively correlated and no male will emerge as superior in an aggregation of singing males. The present thesis addresses the question on which cues decision making is based and how these relevant cues of a male’s song are integrated during the decision process of a female. To this aim no-choice and choice experiments with 6 species of field crickets were conducted. Experiments systematically varied pulse rate, modulation depth, intensity, chirp/trill arrangement and temporal shifts of synchronously presented signals. Furthermore, tests for transitivity of preferences examined if female choice behavior is based on rational or comparative decision making mechanisms. In summary, the results reveal that sensory processing underlying female decisions is similar in the 6 species studied here. Incoming signals are analyzed separately in bilaterally paired networks with parallel pathways for signal attractiveness and signal intensity. A gain-control mechanism fuses the outcome of both pathways and signal intensity is weighted by pattern attractiveness. Thus localization is not independent from signal recognition. Despite this general scheme remarkable characteristic differences between species were observed in pattern recognition, processing of signal intensity and weighting of signal intensity. Closely related species exhibited more similar preferences than unrelated species. Furthermore the tests for transitivity of preferences indicated that females use comparative decision making mechanism and contradicted rational mate choice.
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Shannon, Patrick. "Presumptive wing morph and thermal preference in juvenile sand crickets (Gryllus firmus)." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60510.
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The influence of photoperiod and genotype on thermal preference of juvenile Gryllus firmus was explored. Both rearing condition and genotype affect temperature preference. The following results were obtained: (1) the wing morph of juveniles raised at 28$ sp circ$C 16hL:8hD is determined before 20 days post hatching. (2) Crickets distribute themselves on the apparatus differently in the presence of a thermal gradient than in its absence: such controls for positioning preference are rare in the literature. (3) Juveniles younger than 20 days old tend to choose higher surface temperatures and achieve higher body temperatures if either rearing photoperiod or selection predisposes them to microptery and choose lower temperatures if they are predisposed towards macroptery. (4) The differences in thermal preference between presumptive macropters and micropters remains significant after differences in body size are taken into account. The differences in thermal preference could act as a novel mechanism for lowering the heritability of wing morph.
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Mulcahey, Thomas Ian. "Autonomous cricket biosensors for acoustic localization." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33833.
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The goal of this project was to design networked arrays of cricket biosensors capable of localizing sources such as footsteps within dangerous environments, with a possible application to earthquake detection. We utilize the cricket's natural ability to localize low frequency (5 Hz - 600 Hz) acoustic sources using hair-covered appendages called cerci. Whereas previous investigations explored crickets' neurological response to near field flows generated by single frequency steady-state sounds, we investigated the effects of transient waveforms, which better represent real world stimuli, and to which the cercal system appears to be most reactive. Extracellular recording electrodes are permanently implanted into a cricket's ventral nerve cord to record the action potentials emanating from the cerci. In order to calibrate this system, we attempt to find the relationships between the frequency and direction of acoustic stimuli and the neurological responses known as spike trains, which they elicit. The degree of habituation to repeated signals that exists in most neurological systems was also experimentally measured. We process the signals to estimate frequency and directionality of near field acoustic sources. The design goal is a bionic cricket-computer system design capable of localizing low frequency near field acoustic signals while going about its natural activities such as locomotion.
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Bradford, Michael J. "The role of environmental heterogeneity in the evolution of life history strategies of the striped ground cricket /." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70319.
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I examined the effect of heterogeneity in the thermal environment on the life history of the cricket Allonemobius fasciatus. Variation in the life cycle was the result of a mixture of phenotypic plasticity and genetic differentiation in phenology-related traits along a latitudinal cline in growing season. Females from a partially bivoltine population have a conditional life history because they can adjust the proportion of diapause eggs in accordance with the likelihood that a second generation will grow and reproduce before winter. The thermal environment is not variable enough to result in the evolution of a marked bet hedging response, as is predicted by theory. A quantitative genetic analysis of the diapause reaction norm revealed significant heritabilities as well as correlations with other traits that could be related to common physiological mechanisms.
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Ferreira, Marna. "Evolutionary implications of variation in the calling song of the cricket Gryllus bimaculatus De Geer (Orthoptera : Gryllidae)." Diss., University of Pretoria, 2006. http://hdl.handle.net/2263/23394.
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Thomas, William Buford. "THE DISTRIBUTION, BIOLOGY, AND MANAGEMENT OF THE INDIAN HOUSE CRICKET GRYLLODES SUPPLICANS (INSECT, PEST, URBAN, INTRODUCED, SOUTHWEST UNITED STATES)." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275465.
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Tyler, Frances. "Sexual selection and reproductive isolation in field crickets." Thesis, University of Exeter, 2012. http://hdl.handle.net/10036/4277.
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Barriers to interbreeding limit gene flow between sister taxa, leading to reproductive isolation and the maintenance of distinct species. These barriers come in many forms, and can act at different stages in the reproductive process. Pre-copulatory barriers may be due to individuals discriminating against heterospecifics in mate choice decisions. These decisions may be informed through a range of sensory modalities. If a female is mated and inseminated, then there may be multiple postmating-prezygotic barriers that affect the success of heterospecific sperm in attaining fertilisations. Post-zygotic barriers can be very early acting, resulting in embryonic fatality, or may be later acting, affecting the fitness of hybrid offspring. In this thesis I investigate potential reproductive barriers between the interbreeding field crickets Gryllus bimaculatus and G. campestris. I find that females of both species show only weak preference for conspecific calling song, and may even respond phonotactically to songs typical of heterospecific males. Female G. bimaculatus are repeatable in their preferences and strength of response. G. bimaculatus females presented with synthetic songs prefer those with longer inter-pulse intervals, whereas G. campestris show no discrimination between these songs. Upon meeting, G. campestris females strongly discriminate against heterospecific males, behaving aggressively towards them. This is likely driven by females responding to close range species recognition cues, including chemoreception. The species differ in their cuticular hydrocarbon profiles, and females that are no longer able to use their antennae to receive chemosensory information reduced their aggressive behaviour towards heterospecific males. G. bimaculatus females will mate with heterospecific males, though less readily than to conspecifics. When sequentially mated to both conspecific and heterospecific males, these females will preferentially take up and store sperm from the conspecific male, and sperm from conspecific males is more likely to sire offspring than would be predicted from the proportion of sperm in storage. Eggs from inter-species mating pairs are less likely to begin embryogenesis, and are more likely to suffer developmental arrest during the early stages of embryogenesis. However hybrid embryos that survive to later stages of development have hatching success similar to that of pure-bred embryos. After mating, phonotaxis of G. bimaculatus females towards male songs follows a pattern of suppression and subsequent recovery, likely triggered through detection of seminal proteins transferred in the male ejaculate, or detection of mechanical filling of the spermatheca. This pattern of suppression and recovery of phonotaxis does not differ between females mated to conspecific or heterospecific males. Females that lay few or no eggs do not experience a refractory period.
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Green, Kelly-Ann. "Acoustic signalling and mate choice in field crickets." Thesis, University of Exeter, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493641.
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In this thesis I investigate acoustic signalling and mate choice in the field crickets Giyllus bimaculatus and Gryllus campestris. I measured female response to calling song and courtship song In G. bimaculatus to address a number of questions. I looked at intrinsic factors affecting female mate choice by measuring female response to calling song throughout their reproductive lives and examining the effect of mating. I found that female choosiness but not magnitude of response to calling song was affected by age. I also found that non-virgin females were as choosy as virgin females but responded less. These results suggest that female choice is temporally plastic and that choosiness is costly.
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Baliga, Roshan Bantwal 1981. "Rapid coordinate system creation and mapping using Crickets." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/26718.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (leaves 55-56).
In this thesis, I describe a system that lays the foundation for context-aware applications. This system allows a user to set up a reference coordinate system in a room, using three Cricket listeners attached to a wooden frame. The system then assigns coordinates to Cricket beacons, which are placed on the ceiling. Finally, by using the frame in conjunction with a laser range finder, the user can generate a map of the room in the reference coordinate system, complete with features including doors, walls, and windows. This thesis also describes necessary changes we implemented that made the Cricket positioning system much more accurate.
by Roshan Bantwal Baliga.
M.Eng.
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Fisher, David Newton. "Social networks and individual behaviour variation in wild crickets." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/21128.
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Individuals engage in competitive and cooperative interactions with conspecifics. Furthermore, within any population of interacting individuals there are typically consistent differences among-individuals in behavioural traits. Understanding the importance of both these types of individual-specific behaviours allows us to understand why populations are structured as they are, why individuals show apparently limited behavioural flexibility, and how these elements link to population-level properties. I used extensive video camera monitoring of a population of wild field crickets (Gryllus campestris) to study the interactions and behaviours of uniquely identified individuals. I studied the shyness, activity and exploration of individuals of this population across contexts: from young to old and between captivity and the wild. This allowed me to confirm that individuals were relatively consistent across their adult lifetimes for all three traits, but only consistent between captivity and the wild for activity and exploration. I then found that high activity levels were positively related to high mating rates and short lifespans. Crucially, lifetime mating success was not related to activity level, indicating that the trade-off between lifespan and mating success was sufficient to allow variation in activity level to persist across generations. I also found that cricket social network structure is stable across generations despite the complete turnover of individuals every year. This social network structure influences sexual selection, with some male crickets heavily involved in networks of both pre- and post-copulatory competition, yet males are unable to use pre-copulatory competition to avoid post-copulatory competition. Additionally, positive assortment by mating rate between males and females may reduce the fitness of males with high mating rates, as they face stronger sperm competition. Finally, I used actor-based models to determine the factors predicting cricket social network structure and to test and reject the social-niche hypothesis for the maintenance of among-individual variation in behaviour. I also demonstrated that little else is needed in a stochastically changing network aside from positive assortment by mating rate to simulate a population with a similar skew in mating success to the one observed in the real cricket population. These results give insights into the importance of trade-offs and stochasticity in maintaining the extensive variation in the natural world.
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Franzén, Louise. "Manipulation of monoamines and effects on behavior in crickets." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-140444.
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Blankers, Thomas. "Acoustic communication, sexual selection, and speciation in field crickets." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17553.
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Die vorliegende Dissertation verbindet Ergebnisse aus neuroethologischen, verhaltensbiologischen, quantitativ genetischen und genomischen Ansätzen bei Feldgrillen (Gryllus), um neue Erkenntnisse über die Rolle von sexueller Selektion bei Artbildung zu erlangen. Es wird gezeigt dass multivariate Gesangspräferenzen von Grillenweibchen von wenigen Merkmalen abhängen und zwischen Arten ähnlich sind, während sich Männchengesänge in allen Merkmalen unterschieden. Verschiedene Ebenen der Gesangserkennung sind durch unterschiedliche Präferenzfunktionen charakterisiert. Multivariate Präferenzen können also gleichzeitig verschiedene Indikatoren für Paarungspartnerqualität aus den Gesangsmerkmalen erkennen. Eine polygene genetische Architektur der Gesangsmerkmale und der Präferenz wurde beobachtet und weist auf eine eher langsamere Divergenz hin, obwohl gonosomale Vererbung mehrerer Gesangsmerkmale höhere Evolutionsraten zulässt. Starke Kovarianz zwischen den Merkmalen die direkt sexueller Selektion unterliegen und Merkmale, die nicht direkt von Weibchen gewählt werden, zeigen, dass indirekte Selektion teilweise für die markante Divergenz der Gesänge verantwortlich sein könnte, trotz begrenzter Divergenz der Präferenzen. Ferner zeigte ein Artvergleich der multivariaten Gesangsmerkmale, dass die Form der Präferenzfunktion die Ausrichtung der Kovarianzen und damit die erwartete Selektionsantwort der männlichen Gesänge beeinflussen kann. Simulationen ergaben starke Hinweise auf Genfluss zwischen zwei nahverwandten Arten über einen langen Zeitraum . Nur wenige Contigs zeigten hohe genetische Divergenz und hohe Raten nicht-synonymer Polymorphismen. Diese stimmten aber mit Genen überein, die experimentell nachgewiesene Funktionen in neuromuskulärer Entwicklung und im Paarungsverhalten haben. Zusammen zeigen die Ergebnisse das Potential von sexueller Selektion bei der Entstehung und Aufrechterhaltung von reproduktiver Isolation zwischen Arten.This thesis integrates insights from neuro-ethological, behavioural, quantitative genetics, and genomic approaches in field crickets to provide novel insights in the role of sexual selection in speciation, in particular focusing on speciation with gene flow. It was shown that song preferences depend on few traits and are similar across species while the male song has diverged strongly in all traits. Because the different levels of song recognition are characterized by different types of preference functions, it is conceivable that multivariate preferences can extract various cues for mate quality from different traits simultaneously. A polygenic genetic architecture was found for song traits and preferences, probably limiting divergence rates. However, sex-chromosomal inheritance of some song traits may have allowed for somewhat higher rates. Strong covariance was found between traits that are under sexual selection and traits that are not directly selected by females. This indicates that indirect selection may be responsible in part for striking multivariate divergence in the male calling song despite limited divergence in female preferences. Furthermore, comparing multivariate song traits among species showed that the shape of the preference function can affect the orientation of trait covariance and thereby the selection responses of the male song. Coalescent simulations revealed evidence for a long history of gene flow between two closely related cricket species. Only few contigs with high genetic divergence and high rates of non-synonymous SNPs were found, but many of those that were highly diverged matched genes with experimentally proven functions in neuromuscular development and courtship behavior. Together, these findings underline the potential for sexual selection to drive reproductive isolation.
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DeRose, Marc A. "The effect of inbreeding in various traits in a colonizing wing dimorphic cricket, Gryllus firmus." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0025/MQ50755.pdf.
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Samson, Annie-Helene. "Neural encoding of ultrasound direction in a cricket (T. oceanicus) interneuron." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33835.
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Binaural comparison of intensity is the basis of sound localisation in crickets. Two features of the neural response, response strength and response latency, can encode intensity. Therefore, binaural difference in spike-count and in latency can be used as sound localisation cues. In this work, I investigate the effects of ultrasound intensity and pulse-rate on sound localisation cues as well as the directionality of the response in an ultrasound-sensitive interneuron, AN2. I found that habituation, a decline in neural response, decreases binaural cues encoded in spike-count but increases the cues encoded in first-spike latency. In addition, binaural spike-count and latency difference encode the exact location of ultrasound pulses with similar reliability. As crickets are submitted to habituating stimuli in their natural environment, latency difference is a more useful cue than spike-count difference to locate an ultrasound, although comparison of these results with a previous study suggests that crickets use predominantly binaural difference in spike-count to localise ultrasound.
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Hildebrandt, Kai Jannis. "Neural adaptation in the auditory pathway of crickets and grasshoppers." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2010. http://dx.doi.org/10.18452/16150.
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Neuronale Adaptation dient dazu, eine Sinnesbahn kurzfristig an die aktuelle Umgebung des Tieres anzupassen. Ihr zeitlicher Verlauf lässt sich in der Antwort einzelner Nervenzellen direkt beobachten. Der Adaptation unterliegen eine Vielzahl verschiedener Mechanismen, die über die gesamte Sinnesbahn verteilt sein können. In der vorliegenden Arbeit wurde der Versuch unternommen, diese unterschiedlichen Betrachtungsebenen zusammenzuführen. Dazu wurden mehrere experimentelle und theoretische Studien durchgeführt. In zwei der vorgestellten Studien wurden Kombinationen aus Strominjektionen und akustischen Reizen verwendet, um intrinsische Adaptation von Netzwerkeffekten zu trennen. Dabei ergab sich in einer experimentellen Studie am auditorischen System der Heuschrecke, dass die Adaptationsmechanismen, die in verschiedenen Teilen der Hörbahn rekrutiert werden, sehr stark von Identität und Funktion der jeweils untersuchten Nervenzelle abhängen. Ähnliche Methoden ermöglichten es, im auditorischen System der Grille präsynaptische Hemmung als Substrat für die wichtige mathematische Operation der Division zu identifizieren. Zusätzlich wurden Modellierungen durchgeführt, bei denen die Frage bearbeitet wurde, wo Adaptation in der Hörbahn wirken sollte, bezogen auf zwei verschieden Aufgaben: die Lokalisation eines Signals und die neuronale Abbildung dessen zeitlicher Struktur. Die Ergebnisse dieser Studie deuten darauf hin, dass die Anforderungen für diese beiden Aufgaben sehr unterschiedliche sind. In einer vierten Studie wurde untersucht, ob die Adaptation in einem auditorischen Interneuron der Grille dazu dient, die gesamte sensorische Umgebung gut abzubilden, oder ob durch die Adaptation eine Abtrennung des jeweils lautesten Signals erreicht werden kann. Zusammenfassend lässt sich sagen, dass sowohl die Adaptationsmechanismen, als auch deren genaue Platzierung innerhalb der sensorischen Bahn wesentlich für Sinnesleistungen sind.Neural adaptation serves to adjust the sensory pathway to the current environment of an animal. While the effect and time course of adaptation can be observed directly within single cells, its underlying cause is a combination of many different mechanisms spread out along the sensory pathway. The present work has the objective to unite these different levels of understanding of the term adaptation. In order to do so, several experimental and theoretical studies were carried out. In two of these studies, a combination of current injection and auditory stimulation was used, in order to disentangle intrinsic adaptation from network effects. In one of the studies, carried out in the auditory system of locusts, it was revealed that the mechanisms behind adaptation that are activated within different parts of the auditory system depend critically on identity and function of the cell under study. Similar methods enabled the identification of presynaptic inhibition as a possible mechanisms behind the important mathematical operation of division in the auditory system of crickets. Additionally, a modeling study pursued the question, where adaption should work in the auditory system from the perspective of two different tasks of sensory processing: identification of a signal and localization of its source. The results obtained from the model suggest conflicting demands for these two tasks and also present a solution of this conflict. In a fourth study, it was asked wether adaptation in the auditory system of crickets serves to guarantee optimal representation of the entire sensory environment or if it helps to separate one most important signal from the background. In summary, not only which mechanisms of adaptation are at work is of crucial importance for sensory processing, but also the exact placement of these along the pathway.
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Marsat, Gary. "Temporal coding and auditory processing in the prothoracic ganglion of crickets." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103000.
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We used the auditory system of crickets as a model system to examine the importance of temporal coding in sensory processing. The bilaterally paired Ascending Neurons 1 and 2 (AN1 and AN2) of crickets receive inputs from the auditory receptors on one side and carry the information to the brain. We used stimuli with either conspecific-like or predator-like (i.e. bats) carrier frequency to quantify the accuracy with which the interneurons code the information contained within the amplitude modulation (AM) envelope of the stimulus. AN1, which is tuned to the dominant carrier frequency of cricket songs, selectively codes the limited range of amplitude-modulation frequencies that occur in these signals. AN2, which is most sensitive to ultrasound, serves as a "bat-detector" and codes a broader range of AM frequencies, as occur in bat calls.A striking characteristic in AN2's responses to ultrasound is the presence of bursts of high-frequency spiking separated by relatively sparse spikes. We examined the relative importance of isolated spikes and bursts in the processing of ultrasound. We showed that bursts reliably signal the occurrence of salient amplitude increases. Furthermore, we showed that burst, but not isolated spikes, reliably predict behavioural responses. We suggest AN2 encodes behaviourally important information with bursts.
The Omega Neuron 1 (ON1) responds to conspecific signals and to the ultrasonic echolocation sounds. ON1's temporal coding properties vary with carrier frequency, allowing it to encode both of these behaviourally important signals. Furthermore, the temporal coding properties of ON1 in response to cricket-like sound and bat-like sound match those of AN1 and AN2 respectively.
ON1 is a source of contralateral inhibition to AN1 and AN2, enhancing binaural contrast and facilitating sound localization. We used dichotic stimulation to examine the importance of the temporal structure of contralateral inhibition for enhancing binaural contrast. Contralateral inhibition degrades the accuracy with which amplitude modulation is encoded by AN 1 and AN2, but only if the temporal pattern of inhibitory input matches that of excitation. Our results show that the CF-specific coding properties of ON1 allow this single neuron to enhance localization cues most effectively for both cricket-like and bat-like acoustic signals.
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Seidel, Robin. "Mechanical dynamic response of airflow sensors of airflow sensors of crickets." Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493806.
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Insects have evolved very elaborate sensing systems. The airflow sensors of crickets are among the most sensitive sensors in the animal world. The sensor comprises a thin hair, which protrudes from the surface of the cuticle and sits in a specialised socket. Its elliptical base is surrounded by a flexible joint membrane to allow the hair to rotate. The polarity of the base restricts the rotation of the hair to a preferred plane of movement. The results of the morphometric analysis of the airflow sensors presented in this study show that the maximal diameter of the hair is a strong predictor for the other parameters determining the sensors geometry, such as the hair length, its socket geometry, as well as the hair's elliptical base, which is otherwise hidden within the socket and out of view unless the hair and its base are removed.
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Nguyen, Khuong Ba. "A new nematode parasite of mole crickets its taxonomy, biology and potential for biological control /." Gainesville, FL, 1988. http://www.archive.org/details/newnematodeparas00nguy.
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Simons, Andrew M. (Andrew Michael). "The effect of environmental variability on heritabilities and genetic correlations of traits in the field cricket, Gryllus pennsylvanicus /." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69659.
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The amount of heritable variation and the pattern of genetic covariation in traits are the chief determinants in the evolution of a population, at least over the short term. A preponderance of heritability (h$ sp2)$ and genetic (r$ rm sb g)$ experiments are performed under laboratory conditions which are characterized by low levels of environmental variability. This thesis describes the investigation of the effects of environmental heterogeneity on phenotypic components of variance and covariance. Full-sib families of the field cricket, Gryllus pennsylvanicus, were split between a homogeneous laboratory environment and a more variable field environment. The values of h$ sp2$ were, on average, lower in the variable field environment, with a mean reduction of 19%. Development time was an exception, exhibiting high levels of additive variance in the field. Substantial decreases in generic components of variance contributed to the lower field h$ sp2$ estimates, as well as the expected increases in the components of environmental variance. Within-environment r$ rm sb g$ among morphological traits were not found to differ between the two environments. Laboratory measures of r$ rm sb g$ involving life history traits, though, were not found to reflect the same correlations measured in the heterogeneous environment. A significant negative genetic correlation between fecundity and development time was found in the field environment, yet was not observed in the laboratory. Male-female genetic correlations between morphological traits were high (all r$ rm sb g>0.73),$ and were consistently higher in the field environment than in the laboratory. The genetic correlations between the sexes in development time followed the same trend, but gonad weight showed no similarity between the sexes in either environment. Across-environment correlations within each trait are also discussed.
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Aslanzadeh, Shervin. "Risk perception and antipredatory behaviour of locusts and crickets versus predation strategies of Central netted dragon (Ctenopherus nuchalis)." Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/10091.
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Predation is among the selective forces that shape the phenotype and lifestyle of prey. Different prey types may show different antipredatory responses to the same predator or level of risk based on their ability to avoid predation. I tested antipredatory behaviour of prey species, the Australian plague locust, Chortoicetes terminifera, and the cricket, Acheta domestica, against a predator, the Central netted dragon, Ctenopherus nuchalis. Many theoretical and empirical studies suggest that increased safety has resulted in the evolution of aggregation or group living in prey species. I tested the general idea that being a member of a larger and denser group increases safety among prey. I quantified the predation behaviour of the lizards and the antipredatory strategies of the locusts and crickets in the laboratory using high and low densities of prey and the two phases of C. terminifera; solitarious and gregarious locusts. I compared the number of attacks and success rate of the predator between high and low density groups of prey to determine the influence of prey density on the behaviour of the predator. To investigate differences in level of risk perception among prey with different lifestyles and escape abilities, antipredatory behaviour; escape initiation distance and activity level, of solitarious and gregarious locusts were compared. Additionally, injured gregarious locusts were used to test if disability of prey leads to behavioural changes that indicate that a higher level of risk is perceived by the prey. I also compared attack strategies of juvenile and adult lizards capturing prey. Lizards were more successful attacking groups of locusts than groups of crickets. Prey capture efficiency of lizards was not lower when preying on high density locust groups; although locusts benefit from a higher level of safety due to encounter-dilution effect. Moreover, solitarious and injured gregarious locusts behaved in a manner that indicates a higher perceived risk of predation compared to intact gregarious locusts and they relied more heavily on crypsis to avoid predation. Adult lizards showed faster attack speed and chose larger attack distances than juvenile lizards. In addition, lizards chose smaller attack distances when prey moved directly toward the lizards. In conclusion, prey aggregation or sociality provides more safety for prey individuals through the concealing mechanisms of group living and predators choose their attack strategies based on their physical performance and/or prey behaviour.
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Alagirisamy, Pasupathy Sangareddy. "Vibro-Acoustic and Fluid Flow Response Behaviour of Airflow Sensors of Crickets." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.533779.
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deCarvalho, Tagide. "The adaptive significance and prevalence of courtship feeding in Hawaiian swordtail crickets." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8501.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Biology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Barbara, Kathryn Ann. "Management of pest mole crickets using the insect parasitic nematode Steinernema scapterisci." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0009590.
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Mallard, Samantha. "Fluctuating asymmetry and reproduction in the field crickets Gryllus bimaculatus and Gryllodes sigillatus." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251966.
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Bjernelind, Fredrik. "I Can no Longer Hear the Crickets : On Heterosonic Sounds, Noises and Silences." Thesis, Konstfack, Institutionen för Konst (K), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-5216.
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This essay engages in a reflection on my degree project for Art in the Public Realm Jag kan inte längre höra syrsorna / I Can no Longer Hear the Crickets which is a spatial sound work, an installation or “auditorium” that consists of what I in this text will call “heterosonic” audio. Heterosonic sounds are limit-phenomena of audition that cannot be defined as belonging to either the audible (sonic) or inaudible (infra- and ultra-sonic) parts of the frequency spectrum, nor to the sonorous or strictly physio-acoustic side of sound. Not heard nor silent, it designates sounds that (most often very high in pitch) – like the chirping of crickets, electro-acoustic “teen deterrents”, some screeching train breaks or ringing byproduct noises of electronic equipment – disappear with age, and that is perceivable by one individual's sense apparatus but not by an other's, audible to one ear and inaudible to the other and vice versa. The heterosonic is a displaced phenomena that refuses to act as an external and mediating object between different experiences, in other words not belonging in the empirical and shared world. At the same time it is a moment in everyday events that fractures the intimacy of my own immediate experience and discloses a relational but contradictory (heterological) dimension of individual human perception; asymmetrically intersubjective, social and even interspecific aspects. The heteros – the anonymous “other” – of this hearing has no proper place in or outside my own limits but haunts me as what is otherwise in the same. It is a background noise of silence, discordance of the multivocal, a transformative listening to a sonic dimension of potentiality.
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Webb, Karen Lynn. "The quantitative genetics of sound production in Gryllus firmus /." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59905.
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The species-specific calling songs of male crickets are used by females for species recognition and mate choice. Heritabilities of variation of morphological structures involved in song production, components of the calling song, and body size were estimated for G.firmus. All morphological structures were shown to possess significant additive genetic variation (h$ sp2 sb{ rm S+D} > 0.42)$. One of the five song components examined, pulse rate, was shown to have a significant heritability (h$ sp2 sb{ rm S+D}$ = 0.35). Due to the low correlation between body size and song components, it is unlikely that female G.firmus could use the calling song to assess male body size or wing morph (micropterous or macropterous).
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Eaton, Carrie Elizabeth Diaz. "Ion Channel Dynamics in Interneuron Models of the Cricket Cercal Sensory System." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/EatonCED2004.pdf.
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Pyenson, Benjamin. "Independent regulation of physiological and behavioural maturation of reproduction in female crickets, Gryllus firmus." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=106596.
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Examples from vertebrates as well as insects suggest that physiological and behavioral traits are coupled in reproductive development. In the first days of adulthood, oocyte development and sexual receptivity of Gryllus firmus females increase. I explored whether these are mechanistically linked by Juvenile Hormone (JH), which has been implicated in gonadal development and sexual behavior in other insects. Application of a JH analog, methoprene, accelerates oocyte maturation and triggers flight-muscle histolysis, but does not affect sexual receptivity. These results are consistent with those of other studies suggesting that physiological and behavioral components of sexual maturation in crickets are not under common hormonal control. Other factors may regulate the development of sexual receptivity.Selon la littérature scientifique, les traits physiologiques et comportementaux de certaines espèces de vertébrés et d'insectes seraient intimement liés à leur développement reproductif. Dès les premiers jours de la vie adulte, le développement des ovocytes, ainsi que la réceptivité sexuelle de la Gryllus firmus femelle augmentent. Cette étude explore si ces deux processus sont liés avec le Juvenile Hormone (JH), qui semble être impliqué dans le développement gonadique et le comportement sexuel chez d'autres insectes. Les résultats suggèrent que l'application d'un analogue JH, methoprene, accélèrerait la maturation des ovocytes et déclencherait l'histolyse des muscles de vol, mais serait non-liée à leur réceptivité sexuelle. Les résultats sont en ligne avec ceux d'autres études qui suggèrent que les volets physiologiques et comportementaux de la maturation sexuelle chez les grillons ne sont pas sous le même contrôle hormonal. D'autres facteurs pouvant réguler le développement de la réceptivité sexuelle seront discutés.
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Mangan, Michael. "Visual homing in field crickets and desert ants : a comparative behavioural and modelling study." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5678.
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Visually guided navigation represents a long standing goal in robotics. Insights may be drawn from various insect species for which visual information has been shown sufficient for navigation in complex environments, however the generality of visual homing abilities across insect species remains unclear. Furthermore variousmodels have been proposed as strategies employed by navigating insects yet comparative studies across models and species are lacking. This work addresses these questions in two insect species not previously studied: the field cricket Gryllus bimaculatus for which almost no navigational data is available; and the European desert ant Cataglyphis velox, a relation of the African desert ant Cataglyphis bicolor which has become a model species for insect navigation studies. The ability of crickets to return to a hidden target using surrounding visual cues was tested using an analogue of the Morris water-maze, a standard paradigm for spatial memory testing in rodents. Crickets learned to re-locate the hidden target using the provided visual cues, with the best performance recorded when a natural image was provided as stimulus rather than clearly identifiable landmarks. The role of vision in navigation was also observed for desert ants within their natural habitat. Foraging ants formed individual, idiosyncratic, visually guided routes through their cluttered surroundings as has been reported in other ant species inhabiting similar environments. In the absence of other cues ants recalled their route even when displaced along their path indicating that ants recall previously visited places rather than a sequence of manoeuvres. Image databases were collected within the environments experienced by the insects using custompanoramic cameras that approximated the insect eye viewof the world. Six biologically plausible visual homing models were implemented and their performance assessed across experimental conditions. The models were first assessed on their ability to replicate the relative performance across the various visual surrounds in which crickets were tested. That is, best performance was sought with the natural scene, followed by blank walls and then the distinct landmarks. Only two models were able to reproduce the pattern of results observed in crickets: pixel-wise image difference with RunDown and the centre of mass average landmark vector. The efficacy of models was then assessed across locations in the ant habitat. A 3D world was generated from the captured images providing noise free and high spatial resolution images asmodel input. Best performancewas found for optic flow and image difference based models. However in many locations the centre of mass average landmark vector failed to provide reliable guidance. This work shows that two previously unstudied insect species can navigate using surrounding visual cues alone. Moreover six biologically plausible models of visual navigation were assessed in the same environments as the insects and only an image difference based model succeeded in all experimental conditions.
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Maxwell, Rhianne Morgan Le. "Modifying the Mineral Profile of Crickets (Acheta domesticus) Using a Supplemented Diet." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1907.
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Captive insectivores may consume invertebrates as all, or part of their overall diet. The challenge with feeding captive insectivores involves the limited number of invertebrate species that are commercially available, and the lack of key nutrients provided by these insects. Among these insects, a naturally occurring low concentration of calcium and an inverse calcium to phosphorus ratio may put insectivores at the risk of developing hypocalcemia. A strategy to correct this nutrient imbalance involves supplementing the insect diet with high concentrations of targeted nutrients – a term referred to as gut-loading. Current industry guidelines recommend feeding a supplemented diet for 48 to 72 h before offering the insect to an insectivore. In the present study, the mineral profile of adult crickets (Acheta domesticus) offered a maintenance diet (1.58% Ca, DMB) are compared to crickets offered a supplemented diet (11.32% Ca, DMB) over 120 h. The supplemented diet produced a cricket with significantly higher calcium concentration compared to the maintenance diet. The calcium concentration of crickets offered the supplemented diet was highest at 48 h (0.63%), but did not achieve a 1:1 Ca:P ratio nor meet the lowest reported nutrient requirements of carnivorous reptiles, omnivorous reptiles, or an insectivorous bird at various life stages. Although the supplemented diet improved the whole body calcium concentration in feeder crickets, the crickets do not provide adequate calcium, iron, or manganese to meet the requirement of insectivores. As evidenced by the current study, the supplemented crickets are not recommended to serve as the sole source of nutrition for an insectivore.
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Padda, Sugjit S. "Stressed Out: Life-History Strategy and the Costs of Multiple Stressors in Gryllus Crickets." Scholarly Commons, 2020. https://scholarlycommons.pacific.edu/uop_etds/3702.
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The frequency, duration, and co-occurrence of several environmental stressors are increasing globally. Multiple stressors may have compounding or interactive effects on animals, resulting in either additive or non-additive costs, but animals may mitigate these costs through various strategies of resource conservation or shifts in resource allocation. Thus, through two related factorial experiments, I measured a range of traits—from those related to life history and behavior to underlying physiology— to investigate the nature of costs (additive, non-additive, or neither additive nor non-additive), cost-mitigating strategies (resource conservation or allocation), and life-history strategy related to multiple stressors. First, I leveraged life-history strategy differences in the sand field cricket, Gryllus firmus, to investigate the individual and interactive effects of food and water limitation on fitness-related traits. Gryllus crickets exhibit a wing dimorphism mediating two distinct life-history strategies—long-winged crickets invest into flight capability while short-winged crickets do not. My results indicate that traits vary in their sensitivity to environmental stressors and stressor-stressor interactions (e.g., flight muscle). I only found support for non-additive costs or single-stressor costs of water and food limitation to fitness-related traits. Water availability had a larger effect on traits than food availability, affected more traits than food availability (wing dimorphism), and mediated the effects of food availability. Second, I investigated the role of life-history strategy in cost-mitigating strategies and further examined the costs (additive or non-additive) of multiple stressors to fitness-related traits, physiology, and behavior. I used the variable field cricket, Gryllus lineaticeps, to examine the costs of a simulated heat wave and water limitation. These stressors resulted primarily in single-stressor or non-additive costs to important traits (e.g., survival, final body mass, and total water content), extensive shifts in resource allocation priorities (e.g., reduced prioritization of body mass), and a limited capacity to conserve resources (heat wave reduced energy use only when water was available). Further, life-history strategy influenced the emergency life history stage (ELHS) because wing morphology and stressor(s) interacted to influence gonad and body mass, boldness behavior, and immunocompetence. Together, these two studies demonstrate that water availability and life-history strategy should be incorporated into future studies integrating important conceptual frameworks of stress (multiple-stressor framework and ELHS) across a suite of traits—from survival and life history to behavior and physiology.
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Atkins, Gordon J. "Identified, sound-sensitive interneurons in the cricket : response properties, morphology, and relationships between structure and function." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72091.
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The responses and morphology of nine sound-sensitive interneurons are described in the cricket Teleogryllus oceanicus. Each of the neurons receives direction-specific input in the prothoracic ganglion, and each projects at least one interganglionic axon. Five of the neurons respond best to high frequencies ($>$10 kHz); four are most sensitive to low frequencies (3-10 kHz). Responsiveness to model calling songs was examined in addition to testing sensitivity to wind and light. Anatomical observations reveal that seven of the neurons receive auditory input via polysynaptic pathways, and that at least five of the neurons have morphology consistent with them providing input to mesothoracic motor neurons which are involved in behavioral responses to sound. Correlations between structure, topographic organization, and spectral sensitivity were found. The structure of one previously identified, auditory neuron was examined and found to change during late post-embryonic life. This represents a novel developmental pattern.
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Gordon, Eric Duane. "Using the penalty immersed boundary method to model the interaction between filiform hairs of crickets." Thesis, Montana State University, 2011. http://etd.lib.montana.edu/etd/2011/gordon/GordonE0811.pdf.
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Fluid-structure interactions are important in a wide range of applications and, due to their complexity, need extensive experimental and computational research. One such example comes from crickets, which have evolutionarily developed an excellent micro-air-flow sensory system. Understanding principles of the cricket' micro-air-flow sensor will help design and manufacture artificial sensors. This thesis focuses on improving and validating a Penalty Immersed Boundary (PIB) model of the cricket sensory system, which consists of hundreds of filiform hairs. Previous efforts by others have modeled the filiform hair as a rigid inverted pendulum. Advantages to the PIB approach over previous models include a flexible fluid solver (previous models used an idealized, analytical flow field), the filiform hairs are not required to be completely rigid, and, most importantly, the entire cerci and all the filiform hairs can be modeled. The first goal was to improve the precision and accuracy of modeling a single filiform hair by adjusting model parameters so that the model predictions more accurately fit experimental data. A second goal was to model a portion of a full cercus based on filiform hair data from a real cricket and use the model to determine the interactions occurring between multiple hairs and identify any evolutionary optimization of the cercal system.
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Allen, Janelle Renée. "BIOGENIC AMINES AND THE MODULATION OF BEHAVIOR IN DOMINANT AND SUBORDINATE MALE CRICKETS (Acheta domesticus)." Miami University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=miami1102705950.
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Imaizumi, Kazuo. "Peripheral representation of sound frequency in cricket auditory system : beyond tonotopy." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36956.
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Crickets provide a useful model system to study how animals analyze sound frequency. While much is known about how sound frequency is represented by central neurons and in behavior, little is yet known about auditory receptor neurons. I investigated physiological and anatomical properties of auditory receptor fibers (ARFs) and functional organization of their axon terminals, using single-unit recording and staining techniques. Behavioral experiments suggest that crickets are sensitive to two broad frequency ranges, centered at 4--5 kHz for acoustic communication and at 25--50 kHz for predator detection. However, cricket ARFs fall into three distinct populations, based on characteristic frequency (CF; low frequency, ∼3--5.5 kHz; mid frequency, 9--12 kHz; ultrasound, ≥18 kHz). One striking characteristic of single ARFs is the occurrence of multiple sensitivity peaks at different frequencies, which implies that the wide audible range of crickets is mediated by these multiple sensitivity peaks, even though CFs of ARFs are clustered at the three small ranges. To understand how populations of ARFs code sound intensity, level-response functions are examined. Physiological parameters derived from level-response functions are diverse, and are systematically related to threshold within each population. Low-frequency ARFs comprise two distinct anatomical types, based on the distributions of axon terminals, which also differ physiologically. Thus, based on CF and anatomy, cricket ARFs can be classified into four distinct populations. To understand how information flows from peripheral to central neurons, the positions of varicosities, i.e. output sites, of ARF axon terminals are mapped on a two-dimensional coordinate system. In crickets, the ARF axon terminals are functionally organized with respect to frequency and intensity. Anatomical organization with respect to threshold is related to physiological organization, which may reduce non-linear effects in postsynaptic
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Mullins, Lydia R. "Testing the effects of glyphosate and a possible tradeoff with immunity on native and non-native species of crickets." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587642768787223.
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Bourgeois, Raymond C. "Phonotactic orientation behavior of tethered flying crickets (Teleogryllus oceanicus) and its dependence on stimulus carrier frequency." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63311.
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Wedell, Nina. "Evolution of nuptial gifts in bushcrickets." Stockholm : Dept. of Zoology, University of Stockholm, 1993. http://catalog.hathitrust.org/api/volumes/oclc/28206160.html.
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Dias, Pedro Guilherme Barrios de Souza [UNESP]. "Novos táxons de Grylloidea da Floresta Latifoliada semidecídua da região de Foz do Iguaçu-PR (Orthoptera, Ensifera)." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/99449.
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dias_pgb_me_botib.pdf: 14287971 bytes, checksum: 033f577c35715b075ecb5ff761584299 (MD5)O escopo do presente trabalho foi analisar e descrever novos táxons de Grylloidea (Orthoptera, Ensifera) da região de Foz do Iguaçu-PR, mais especificamente do Parque Nacional do Iguaçu e da mata ciliar do Rio Mathias Almada. O material analisado foi obtido a partir de coletas realizadas no âmbito de dois projetos de pesquisa desenvolvidos no referido parque entre 2005 e 2008, além de outras na mata do Rio Mathias Almada entre 2002 e 2005. Para tanto, diversos métodos de coletas, tanto ativas quanto passivas, foram utilizados. Doze espécies novas foram descritas, de doze gêneros, pertencentes às famílias Eneopteridae (Tafaliscinae, Tafaliscini & Tafaliscinae, Neometrypini), Phalangopsidae (Phalangopsinae, Neoaclini & Luzarinae, grupos B e C), Podoscirtidae (Hapithinae Neomorphini) e Trigonidiidae (Nemobiinae Nemobiini & Pteronemobiini). Um novo gênero, Taroba (Podoscirtidae, Hapithinae, Neomorphini) foi descrito. As novas espécies são: 1 – Taroba elephantina; 2 – Neometrypus fuscocephalus; 3 – Tafalisca paranaensis; 4 – Ectecous thelythocous; 5 – Eidmanacris ituporanga; 6 – Endecous zefai; 7 – Laranda cataractarum; 8 – Lerneca campestris; 9 – Vanzoliniella almadensis; 10 – Neomorpha meridionalis; 11 – Amanayara naipi; 12 – Zucchiella iguassuensis. Juntamente com as descrições são apresentadas pranchas com caracteres diagnósticos de todos os novos táxons, assim como figuras comparando os mesmos com táxons proximamente relacionados. O material coletado nas duas localidades compunha-se, quase que inteiramente, de novas espécies. Isto se deve à escassez de estudos faunísticos na região do Parque Nacional do Iguaçu, o que reflete a precariedade do conhecimento de toda a fauna de grilos da região Neotropical
The aim of the present work was to analyze and describe new taxa of Grylloidea (Orthoptera, Ensifera) from Foz do Iguaçu area, more specifically, from the Iguaçu National Park and a riparian forest along Mathias Almada River. The material analyzed was obtained from two scientific projects developed at Iguaçu National Park from 2005 to 2008, and collectings along side Mathias Almada River from 2002 to 2005. Several collecting methods, both active and passives, were employed. One new genus, Taroba (Podoscirtidae, Hapithinae, Neomorphini) and twelve new species belonging to the following families were described: Eneopteridae (Tafaliscinae: Tafaliscini & Neometrypini), Phalangopsidae (Phalangopsinae, Neoaclini & Luzarinae, groups B e C), Podoscirtidae (Hapithinae, Neomorphini) and Trigonidiidae (Nemobiinae: Nemobiini & Pteronemobiini). The new species are: 1 – Taroba elephantina; 2 – Neometrypus fuscocephalus; 3 – Tafalisca paranaensis; 4 – Ectecous thelythocous; 5 – Eidmanacris ituporanga; 6 – Endecous zefai; 7 – Laranda cataractarum; 8 – Lerneca campestris; 9 – Vanzoliniella aquita; 10 – Neomorpha meridionalis; 11 – Amanayara naipi; 12 – Zucchiella iguassuensis. Plates with diagnostic characters of all new taxa as well as illustrations comparing them to closely related ones were provided. The great majority of the material obtained from both localities belongs to new species, which points to the scarcity of faunistic studies in the area, which reflects the precarious state of knowledge of the cricket fauna from the neotropics as a whole
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Archer, Catharine Ruth. "Food, sex and death : costs of reproduction and the mechanistic basis of ageing." Thesis, University of Exeter, 2012. http://hdl.handle.net/10036/3568.
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Ageing is the progressive decline in physiological performance with age, which is almost universal amongst multicellular organisms. While understanding ageing is an important aim in biological research, our current understanding of how and why we age is incomplete. In this thesis, I examine how sexual selection affects the evolution and mechanistic basis of ageing. I then explore how diet affects lifespan and reproduction in either sex. Finally, I test the hypotheses that oxidative stress, which occurs when cellular levels of Reactive Oxygen Species exceed circulating antioxidant defences causes ageing (i.e. the free radical theory of ageing) and/or constrains life-history strategies. To ask these questions, I employ quantitative genetics in decorated crickets Gryllodes sigillatus to examine the genetic co(variance) of ageing, lifespan, reproductive effort, oxidative damage and antioxidant protection. In the Australian field cricket, Teleogryllus commodus, I apply the geometric framework of nutrition to examine how lifespan, reproductive effort, oxidative damage and antioxidant capacity respond to dietary manipulation. In G. sigillatus, I found that sexual selection caused divergent strategies of age-dependent reproductive effort across the sexes and that this, in turn, promoted different rates of ageing in males and females. I found a trade-off between early reproductive effort and ageing rate in both sexes, although this trade-off was more pronounced in females (Chapter 3). I then explored the mechanistic basis of these sex-specific life-history strategies and, in support of the free radical theory of ageing, I found that oxidative damage was greatest in the shortest lived sex (females) and was negatively genetically correlated with lifespan. Additionally, oxidative damage was a cost of female reproductive effort that accelerated ageing, showing that oxidative stress may mediate sex-specific life-history strategies in decorated crickets (Chapter 4). If sexual selection affects reproduction and lifespan it should promote sex-specific life-history responses to dietary manipulation. In Australian black field crickets Teleogryllus commodus, I found that males and females have distinct dietary optima for lifespan and reproductive effort and that diet mediated a trade-off between these traits. I found that mating affected responses to dietary manipulation and caused sexual dimorphism in dietary intake under choice (Chapter 5). However, oxidative stress did not explain these life-history responses to dietary manipulation across the sexes (Chapter 6): although oxidative damage was greatest in the shortest lived sex (i.e. females), diets that extended lifespan did not reduce oxidative damage. My thesis illustrates the importance of considering sexual selection when considering the evolution and mechanistic basis of ageing. It offers equivocal support for the free radical theory of ageing but shows that oxidative stress may help underpin sex-specific life-history strategies. However, my results highlight that unravelling the relationship between oxidative stress and life-history strategies across the sexes will be a very difficult task.
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Narbonne, Rémi. "Auditory sensitivity in crickets: effects on specific interneurons of a hormonal treatment and of a circadian rhythm." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21978.
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Animals that use hearing organs are always subject to evolve and adapt to new environmental situations hence they improve their hearing sensitivity in order to counteract the predators' pressure. In crickets, for instance, a recent study, on a wing-dimorphic species, showed that flight capable crickets (long-winged) are more sensitive to ultrasound than crickets incapable of flight (short-winged). The developmental decision to become a long- or short-winged individual occurs during the last two larval instars, and it was suggested that the level of juvenile hormone (higher in short-winged individuals) has a role in that decision. A juvenile hormone analog, methoprene, was applied on females Teleogryllus oceanicus during their last stage of development. Subsequently, electrophysiological experiments were done during crickets' adulthood. The results show a decrease in ultrasound sensitivity in both AN2 and ON1 auditory interneurons after the hormonal treatment. In addition, analysis of the firing rate indicates a decrease in the number of spikes produced when the interneurons were stimulated in methoprene-treated crickets. We did not observe any effect of the treatment on the interneurons responses to cricket-like carrier frequencies. Hence, the ultrasound sensitivity in primary auditory interneurons in crickets might be influenced by physiological factors such as, the concentration of the juvenile hormone during the development. Furthermore, since ultrasound sensitivity in crickets is important, we asked if the sensitivity of Gryllus assimilis changes during the different periods of a day. We found a decrease in the ultrasound sensitivity as well as in the firing rate and in the bursting rate of AN2 auditory interneuron at dusk. Feature detection analysis of AN2 responses indicated that, at dusk, false-alarm percentages produced by this neuron were lower than during other periods of the day. Thus, AN2 ultrasound responses change throughout a day time.Les animaux ayant une acuité auditive développée sont toujours sujet à évoluer et à s'adapter à de nouvelles situations pour améliorer leurs capacités à survivre à la pression exercée par les prédateurs. Chez le grillon, en fait, une récente étude menée sur une espèce ayant les ailes dimorphiques, a démontré que les grillons ayant la capacité de voler (longues-ailes) étaient plus sensibles aux ultrasons que ceux qui étaient incapable de voler (courtes-ailes). La décision développementale de devenir un grillon aux longues ou courtes ailes se fait durant les deux derniers stages larvaires. En plus, il a été suggéré que le niveau d'hormone juvénile (plus élevé chez les individus à courtes ailes) joue un rôle dans cette décision. Une solution de « methoprene », une hormone semblable à l'hormone juvénile, fût appliquée sur des femelles Teleogryllus oceanicus durant leur dernier stage de développement. Par ailleurs, les expériences électrophysiologiques furent exécutées lorsque que les grillons étaient adultes. Les résultats obtenus démontrent une diminution de sensibilité pour les ultrasons dans les deux interneurones étudiés (AN2 et ON1) chez les grillons ayant reçus le traitement hormonal. En plus, l'analyse de la fréquence maximale de décharge des grillons traités au « methoprene » nous indique aussi une diminution dans le nombre de potentiels d'action produit lors de stimulations avec des ultrasons. Malgré tous ces résultats, nous n'avons observé aucun changement en ce qui attrait à la sensibilité aux fréquences utilisées par les grillons (basses fréquences). Ainsi, nous pouvons conclure que la sensitivité pour les ultrasons chez le grillon pourrait être sous l'influence de la concentration de l'hormone juvénile présente durant le développement. Par ailleurs, parce que la sensibilité auditive aux ultrasons est importante, nous avons évalué la question à propos de possibles changements de$
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Bégin, Mathieu. "Are quantitative genetic constraints to morphological evolution important on an evolutionary time scale? an empirical investigation in field crickets." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84471.
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The evolutionary importance of genetic constraints has always been recognized by biologists, but very little data is available to quantitatively assess the role of constraints in shaping the biology of organisms. The field of quantitative genetics provides the tools necessary to study evolutionary constraints, mainly through the estimation of the matrix of additive genetic variance and covariance (the G matrix). The main goals of this Ph.D. dissertation were to study the persistence of constraints across environments and across species, to explore the consequences of constraints on species divergence, and to try to understand some morphological and life history characteristics of field crickets in light of genetic variation. Populations of seven wing-dimorphic cricket species from the genera Gryllus and Teleogryllus were sampled from the wild and reared in the laboratory. Using multiple statistical approaches to the comparison of G matrices, results revealed little variation in G matrices across species. Moreover, the relatively small effect of rearing environment and of the two wing morphologies on G were shown to be of the same magnitude as variation between species, therefore confirming the general constancy of genetic constraints through evolutionary time scales. Mean trait values, selection regimes and phylogenetic distances were all shown not to be predictors of G matrix variation. In agreement with the constraint hypothesis of quantitative genetic theory, morphological divergence between species was shown to be predictable from a reconstructed ancestral G matrix. In addition, information on genetic variation was used to explain various patterns relating to size, ovipositor length, wing morphology and diapause occurrence in field crickets. Overall, we suggest that genetic constraints, as described by quantitative genetics, have played a major role in shaping the observed biological diversity of field cricket species, a conclusion tha
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Wynn, Helen. "The function of mate guarding in the field cricket Gryllus bimaculatus De Geer (Orthoptera: Gryllidae)." Thesis, University of Derby, 2001. http://hdl.handle.net/10545/264132.
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Dias, Pedro Guilherme Barrios de Souza. "Novos táxons de Grylloidea da Floresta Latifoliada semidecídua da região de Foz do Iguaçu-PR (Orthoptera, Ensifera) /." Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/99449.
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Resumo: O escopo do presente trabalho foi analisar e descrever novos táxons de Grylloidea (Orthoptera, Ensifera) da região de Foz do Iguaçu-PR, mais especificamente do Parque Nacional do Iguaçu e da mata ciliar do Rio Mathias Almada. O material analisado foi obtido a partir de coletas realizadas no âmbito de dois projetos de pesquisa desenvolvidos no referido parque entre 2005 e 2008, além de outras na mata do Rio Mathias Almada entre 2002 e 2005. Para tanto, diversos métodos de coletas, tanto ativas quanto passivas, foram utilizados. Doze espécies novas foram descritas, de doze gêneros, pertencentes às famílias Eneopteridae (Tafaliscinae, Tafaliscini & Tafaliscinae, Neometrypini), Phalangopsidae (Phalangopsinae, Neoaclini & Luzarinae, grupos B e C), Podoscirtidae (Hapithinae Neomorphini) e Trigonidiidae (Nemobiinae Nemobiini & Pteronemobiini). Um novo gênero, Taroba (Podoscirtidae, Hapithinae, Neomorphini) foi descrito. As novas espécies são: 1 - Taroba elephantina; 2 - Neometrypus fuscocephalus; 3 - Tafalisca paranaensis; 4 - Ectecous thelythocous; 5 - Eidmanacris ituporanga; 6 - Endecous zefai; 7 - Laranda cataractarum; 8 - Lerneca campestris; 9 - Vanzoliniella almadensis; 10 - Neomorpha meridionalis; 11 - Amanayara naipi; 12 - Zucchiella iguassuensis. Juntamente com as descrições são apresentadas pranchas com caracteres diagnósticos de todos os novos táxons, assim como figuras comparando os mesmos com táxons proximamente relacionados. O material coletado nas duas localidades compunha-se, quase que inteiramente, de novas espécies. Isto se deve à escassez de estudos faunísticos na região do Parque Nacional do Iguaçu, o que reflete a precariedade do conhecimento de toda a fauna de grilos da região NeotropicalAbstract: The aim of the present work was to analyze and describe new taxa of Grylloidea (Orthoptera, Ensifera) from Foz do Iguaçu area, more specifically, from the Iguaçu National Park and a riparian forest along Mathias Almada River. The material analyzed was obtained from two scientific projects developed at Iguaçu National Park from 2005 to 2008, and collectings along side Mathias Almada River from 2002 to 2005. Several collecting methods, both active and passives, were employed. One new genus, Taroba (Podoscirtidae, Hapithinae, Neomorphini) and twelve new species belonging to the following families were described: Eneopteridae (Tafaliscinae: Tafaliscini & Neometrypini), Phalangopsidae (Phalangopsinae, Neoaclini & Luzarinae, groups B e C), Podoscirtidae (Hapithinae, Neomorphini) and Trigonidiidae (Nemobiinae: Nemobiini & Pteronemobiini). The new species are: 1 - Taroba elephantina; 2 - Neometrypus fuscocephalus; 3 - Tafalisca paranaensis; 4 - Ectecous thelythocous; 5 - Eidmanacris ituporanga; 6 - Endecous zefai; 7 - Laranda cataractarum; 8 - Lerneca campestris; 9 - Vanzoliniella aquita; 10 - Neomorpha meridionalis; 11 - Amanayara naipi; 12 - Zucchiella iguassuensis. Plates with diagnostic characters of all new taxa as well as illustrations comparing them to closely related ones were provided. The great majority of the material obtained from both localities belongs to new species, which points to the scarcity of faunistic studies in the area, which reflects the precarious state of knowledge of the cricket fauna from the neotropics as a whole
Orientador: Ricardo Cardoso Benine
Coorientador: Francisco de Assis
Banca: Edison Zefa
Banca: Carmen Silvia Fontanelli Cristofoletti
Mestre
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Beckmann, Bjorn. "Using citizen science data to reveal the role of ecological processes in range changes of grasshoppers and crickets in Britain." Thesis, University of York, 2017. http://etheses.whiterose.ac.uk/18904/.
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Climatic and land use changes are affecting the distributions of many species and habitats. A detailed understanding of these impacts is critical for conservation and adaptation planning, but much interspecific variability remains unexplained. One reason may be that studies have tended to consider only effects of changes in mean climate, not of annual variation. Using data of the Orthoptera Recording Scheme and additional field observations, I investigated effects of species traits and seasonal variability in weather on the pattern and process of distributional changes of grasshoppers and crickets in Britain over recent decades. I found large changes in the distributions of several species, and relatively greater increases for habitat generalists, species that oviposit in vegetation, and for those with a southerly distribution. In a study of the rapid range expansion of two wing-dimorphic species, Conocephalus discolor and Metrioptera roeselii, I found some of the first evidence for effects of seasonal weather on annual colonisation rates, and for an interaction between the effects of temperature and precipitation. The findings suggest that for some species weather may concentrate dispersal into waves in climatically favourable years. This may increase successful establishment through greater numbers of colonists, and may also be advantageous in fragmented landscapes, allowing species to invest in dispersal only sporadically and under favourable conditions. The results also highlight the importance of considering interactive effects of temperature and precipitation when examining species’ responses to climatic variability. Studies like these are made possible by large-scale, long-term distribution recording by volunteers. However, the unstructured and evolving nature of this "citizen science” makes the data prone to biases that need to be taken into account during analysis. I reviewed current recording of Orthoptera and the scope for its development, and propose a protocol for Orthoptera abundance monitoring by volunteers for future research and conservation applications.
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Blankers, Thomas [Verfasser], R. Matthias [Gutachter] Hennig, Michael G. [Gutachter] Ritchie, and Kerry L. [Gutachter] Shaw. "Acoustic communication, sexual selection, and speciation in field crickets / Thomas Blankers. Gutachter: R. Matthias Hennig ; Michael G. Ritchie ; Kerry L. Shaw." Berlin : Lebenswissenschaftliche Fakultät, 2016. http://d-nb.info/1109846371/34.
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