1,720,962 research outputs found
The Horned Frog
Get PDFRamlah Zainudin, Elvy Quatrin Deka, Nur Amirah Md Sungif, Marly Agoh,
Sharizzaty Mohd Rais, Muhammad Fadzil Amram, Marius Joscha Maiwald,
Aida Safreena Ahmad Puad, Ahmad Hata Rasit and Mohd-Azlan Jayasila
Developing Call Based Dichotomous Key and Understanding Playback Call Responses Among Sarawak Frogs
Get PDFAnurans advertisements calls are very diverse; with each species has its own call. Sound produced by the anurans can be a prezygotic isolating mechanism that ensures the survival of the species, as only the fittest will be chosen by the conspecific female to produce progenies. The objective of this study are 1) To determine unique sound characteristics for species identification, 2) To reconstruct phylogeny based on those unique call characteristics, 3) To validate species status of the anuran being studied using vocalisation by doing playback recording, and 4) To develop a dichotomous key based on advertisement calls. Described here were the advertisement calls of 47 species of Sarawak frogs, with 10 from the Family Bufonidae, three from Dicroglossidae, seven from Megophryidae, eight from Microhylidae, 11 from Ranidae, and eight from Rhacophoridae, recorded from 15 study sites in Sarawak. The calls of the male Sarawak frogs were successfully analyzed and described using SoundRuler Acoustic Analysis ver 0.9.6.0 and further determine whether the call characteristic can be used to differentiate the species. Through the Principal Component Analysis (PCA), Discriminant Function Analysis (DFA) and Multivariate analysis it was discovered that the variations of the advertisement call of Sarawak frogs could be used to discriminate the species. For PCA, a total of 25 variables were meaningful in describing the call characteristics of Sarawak Frogs. As for DFA, the heaviest loaded variables in all three functions are from pulse group. Call note, pulse duration, call energy, call frequency and call intensity are the useful groups in discriminating the frog species. Cluster analysis method partially successful in clustering the frog species based on their advertisement call characteristic, especially the frequency group. Through phylogenetic analysis on the calls, constructed neighbor-joining (NJ) and maximum parsimony (MP) tree produced different topology. Both trees show weak support, with most of the nodes have low bootstrap values. For calls validation, the responses of both male and female frogs from three species were observed by playing the advertisement call of the species at their breeding site. Male of all three species responded to the calls, and almost no reaction from female frogs. Next is developing dichotomous key based on the characters of advertisement calls by using meaningful call characters from PCA and DFA. Dichotomous key based on Sarawak frogs’ call were successfully constructed. The key was successfully tested using Leptolalax gracilis calls. The identification of calling characters that can be used to distinguish frog species are very important as it specifies an alternative approach of classifying anuran species other than morphological and DNA variations. It will useful for quicker species identification, and help in solving the taxonomic status of the frogs, for future management and conservation purposes.
Keywords: Anuran, bioacoustics, call characters, dichotomous key, Sarawak frog
Advertisement calls of seven species of Sarawak frogs from the family Megophryidae
No full textThe vocalization patterns of frogs in the family Megophryidae from Sarawak, Malaysia, play a crucial role in their behavioral ecology. This study aims to document and analyze the advertisement calls of seven Megophryidae species across diverse habitats in Sarawak. Using field recordings and acoustic analysis, distinct call characteristics, including frequency, duration, and temporal patterns, were identified. Advertisement calls were recorded and analyzed using SoundRuler Acoustic Analysis (ver. 0.9.6.0) and Praat Acoustic Software, allowing for species differentiation based on call parameters. The results revealed species-specific variations in vocalization, with pulse note count, note repetition rate, and dominant frequency emerging as the most distinguishing features. Leptobrachium ingeri exhibited the highest number of pulsed notes per call, while Leptobrachella gracilis demonstrated the highest note repetition rate, and Leptobrachella mjobergi produced the highest dominant frequency. These findings enhance our understanding of species-specific vocalizations and their ecological significance, particularly in mate selection, territorial defense, and environmental adaptation. This study underscores the importance of acoustic monitoring in biodiversity conservation and provides a foundation for future research on amphibian communication in tropical ecosystems
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Mating calls of selected sarawak toads (Amphibia: Anura: Bufonidae)
Get PDFThe sound produced by the anurans including toads can be a survival strategy for the selection of fittest males by their conspecific females and a form of effective prezygotic mechanism. Most of the published works on anuran sound production were on true frogs or ranids, yet little is known about sound characteristics of toads. Here we describe the properties of mating calls from six selected toad species from six study sites in Sarawak. Males’ mating calls were recorded and analyzed using SoundRuler Acoustic Analysis ver 0.9.6.0. Call characteristic were subsequently compared for toad species differentiation. The results showed that each species differ in call characteristics, with pulsating note, rate of note repetition and pitch being the most apparent characters. The highest number of pulse notes belongs to Duttaphrynus melanostictus while Ansonia spinulifer exhibited highest pitch and rate of note repetition. These species’ differences in mating call characteristics provide an additional method for anuran species classification besides morphological and molecular DNA data. It is also a very useful guide during field survey as the sound is audible and identification can be made without the need of capturing the toads
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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