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Calling Patterns (calling + pattern)
Selected AbstractsIndividual Male Calling Pattern and Male Mating Success in the European Treefrog (Hyla arborea): Is there Evidence for Directional or Stabilizing Selection on Male Calling Behaviour?ETHOLOGY, Issue 2 2006Thomas W.P. Friedl In anurans, call properties are commonly classified based on within-male variability as being either static or dynamic. Numerous playback experiments in the laboratory have indicated that female preferences based on dynamic call properties are usually strongly directional, while female preferences based on static call properties are often stabilizing or weakly directional. However, there are only few studies demonstrating that female preferences for high values of dynamic call properties indeed exert directional selection on male calling behaviour in natural populations. Moreover, field studies investigating whether female preferences for values of static call properties around the mean of the population lead to currently operating stabilizing selection on male calling patterns in natural populations are completely lacking. Here I investigate for two consecutive breeding seasons male calling patterns and male mating success in a population of individually marked European treefrogs (Hyla arborea), a hylid frog with prolonged breeding season and a lek mating system. Individual male calling pattern as analysed in terms of seven temporal and spectral call properties did not differ between males that survived from one breeding season to the next and those not surviving. None of the seven call properties investigated differed significantly between mated and unmated males, indicating that there is no strong directional selection on male calling behaviour in the study population. However, in one study season males that produced calls with a number of pulses around the mean of the population were significantly more likely to obtain matings than males that produced calls with a number of pulses at the low or high end of the distribution. Thus, this study provides preliminary evidence for the operation of stabilizing selection on a static call property (i.e. the number of pulses per call) in a natural population of an anuran amphibian. [source] Calling behaviour of adult female Helicoverpa armigera (Hübner) (Lep., Noctuidae) of overwintering generation and effects of matingJOURNAL OF APPLIED ENTOMOLOGY, Issue 2 2000M. L. Hou The calling behaviour of overwintering generation females of Helicoverpa armigera and the effects of mating were studied in the laboratory at 24 ± 1°C and under reversed light-dark cycle (16 h light : 8 h dark). Age had a significant influence on calling patterns. Based on calling age, mean number of calling bouts and total calling length of virgin females increased significantly, and mean onset time of calling advanced significantly from calling day 1 to subsequent calling days. Females of the overwintering generation exhibited more short bouts in calling, and some females that initiated calling on a previous day did not call on subsequent days. Mating had no effect on the overall patterns, but did affect calling behaviour. Mated females did not resume calling after mating during the same scotophase and, on the day following mating, mated females called less frequently and for a shorter duration, but thereafter increased to the same level of virgin females of the same calling age. Furthermore, as the moth aged, the percentage of mated females calling was lower than that of virgin females. [source] Elephant calling patterns as indicators of group size and composition: the basis for an acoustic monitoring systemAFRICAN JOURNAL OF ECOLOGY, Issue 1 2003Katharine B. Payne The paper gives evidence that the vocal activity of elephants varies with group size, composition and reproductive status, and that elephants' calling patterns could therefore provide the basis for a remote monitoring system. We examined a 3-week set of array-based audio recordings of savanna elephants (Loxodonta africana), searching for diagnostic acoustic parameters. An acoustic array made it possible to locate recorded sounds and attribute the calls to particular elephants or elephant groups. Simultaneous video recordings made it possible to document visible behaviour and roughly correlate it with vocalizations. We compared several measures of call density in elephant groups containing up to 59 individuals, and found that rates of calling increased with increasing numbers of elephants. We divided all call events into three structural types (single-voice low-frequency calls, multiple-voice clustered low-frequency calls, and single-voice high frequency calls), and found that the incidence of these varies predictably with group composition. These results suggest the value of a network of listening systems in remote areas for the collection of information on elephant abundance and population structure. Résumé Cet article donne des preuves du fait que l'activité vocale des éléphants varie avec la taille du groupe, sa composition et le statut reproducteur, et que le schéma des appels des éléphants pourrait donc constituer la base d'un système de contrôle continu à distance. Nous avons examiné trois semaines d'enregistrements audio d'éléphants de savane (Loxodonta africana) pour chercher des paramètres de diagnostic acoustique. Un arrangement acoustique permit de localiser les sons enregistrés et d'attribuer les appels à des éléphants identifiés ou à des groupes. Des enregistrements vidéo simultanés ont permis de documenter un comportement visible et de le mettre grossièrement en rapport avec les vocalisations. Nous avons comparé plusieurs mesures d'intensité d'appel dans des groupes qui comptaient jusqu'à 59 individus et nous avons constaté que le taux des appels augmentait avec le nombre d'éléphants. Nous avons classé tous les appels en trois types structuraux (appels à basse fréquence d'une voix unique, appels à basse fréquence de voix multiples, appels à haute fréquence d'une voix unique) et nous avons constaté que l'incidence de ceux-ci varie de façon prévisible selon la composition du groupe. Ces résultats incitent à croire qu'un réseau de systèmes d'écoute dans des endroits éloignés serait très utile pour la récolte d'informations sur l'abondance des éléphants et la structure de leurs populations. Introduction [source] Sex differences in the vocal repertoire of adult red-capped mangabeys (Cercocebus torquatus): a multi-level acoustic analysisAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2010Hélène Bouchet Abstract Sex differences in the vocal behavior of nonhuman primates can take various forms: sex-specific call types, differential production of shared call types, or sex discrepancy in phonation. Also, a growing literature is evidencing that systematically analyzing the vocal repertoires of primates at the call level might lead to underestimating their communicative abilities. Here, we present an extensive multi-level analysis of the still unknown vocal repertoire of adult red-capped mangabeys (Cercocebus torquatus), with a special emphasis on sex differences. We collected recordings from seven adult males and seven adult females housed in captivity. We present a structurally-based classification of mangabey calls that we cross-validated by an analysis of the associated contexts of emission. We found 12 sound units (including six sex-specific) that were concatenated to form eight call types (including four sex-specific), which were produced either singularly or in sequences composed of one ("repetition") or several ("combination") call types. We extracted organizational principles that ruled call composition and calling patterns. This revealed a high degree of potentially meaningful variability in terms of semantics and syntax. Male,female discrepancy in terms of phonation could be related to morphological dimorphism and would enable listeners to behave appropriately according to the sex of the caller. Sex differences in repertoire size, structural gradation, and call usage could reflect specificities of male,female social roles. We discuss the pertinence of these sex differences according to social system and habitat quality. Am. J. Primatol. 72:360,375, 2010. © 2010 Wiley-Liss, Inc. [source] | ||||||||||