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Herbert Peremans - One of the best experts on this subject based on the ideXlab platform.

  • Parameters used to generate heterogeneous artificial environments mimicking the cluttered habitats of Rhinolophidae.
    2015
    Co-Authors: Dieter Vanderelst, Marc W. Holderied, Herbert Peremans
    Abstract:

    Parameters used to generate heterogeneous artificial environments mimicking the cluttered habitats of Rhinolophidae.

  • the noseleaf of rhinolophus formosae focuses the frequency modulated fm component of the calls
    Frontiers in Physiology, 2013
    Co-Authors: Dieter Vanderelst, Ya Fu Lee, Inga Geipel, Elisabeth Klara Viktoria Kalko, Yen Min Kuo, Herbert Peremans
    Abstract:

    Bats of the family Rhinolophidae emit their echolocation calls through their nostrils and feature elaborate noseleaves shaping the directionality of the emissions. The calls of these bats consist of a long constant-frequency component preceded and/or followed by short frequency-modulated sweeps. While Rhinolophidae are known for their physiological specializations for processing the constant frequency part of the calls, previous evidence suggests that the noseleaves of these animals are tuned to the frequencies in the frequency modulated components of the calls. In this paper, we seek further support for this hypothesis by simulating the emission beam pattern of the bat Rhinolophus formosae. Filling the furrows of lancet and removing the basal lappets (i.e. two flaps on the noseleaf) we find that these conspicuous features of the noseleaf focus the emitted energy mostly for frequencies in the frequency-modulated components. Based on the assumption that this component of the call is used by the bats for ranging, we develop a qualitative model to assess the increase in performance due to the furrows and/or the lappets. The model confirms that both structures decrease the ambiguity in selecting relevant targets for ranging. The lappets and the furrows shape the emission beam for different spatial regions and frequency ranges. Therefore, we conclude that that the presented evidence is in line with the hypothesis that different parts of the noseleaves of Rhinolophidae are tuned to different frequency ranges with at least some of the most conspicuous ones being tuned to the frequency modulated components of the calls - thus yielding strong evidence for the sensory importance of the component.

  • Dominant Glint Based Prey Localization in Horseshoe Bats: A Possible Strategy for Noise Rejection
    2013
    Co-Authors: Jonas Reijniers, Uwe Firzlaff, Herbert Peremans
    Abstract:

    Rhinolophidae or Horseshoe bats emit long and narrowband calls. Fluttering insect prey generates echoes in which amplitude and frequency shifts are present, i.e. glints. These glints are reliable cues about the presence of prey and also encode certain properties of the prey. In this paper, we propose that these glints, i.e. the dominant glints, are also reliable signals upon which to base prey localization. In contrast to the spectral cues used by many other bats, the localization cues in Rhinolophidae are most likely provided by self-induced amplitude modulations generated by pinnae movement. Amplitude variations in the echo not introduced by the moving pinnae can be considered as noise interfering with the localization process. The amplitude of the dominant glints is very stable. Therefore, these parts of the echoes contain very little noise. However, using only the dominant glints potentially comes at a cost. Depending on the flutter rate of the insect, a limited number of dominant glints will be present in each echo giving the bat a limited number of sample points on which to base localization. We evaluate the feasibility of a strategy under which Rhinolophidae use only dominant glints. We use a computational model of the echolocation task faced by Rhinolophidae. Our model includes the spatial filtering of the echoes by the morphology of the sonar apparatus of Rhinolophus rouxii as well as the amplitude modulations introduced by pinnae movements. Using this model, we evaluate whether the dominant glints provide Rhinolophidae with enough information to perform localization. Our simulations show that Rhinolophidae can use dominant glints in the echoes a

  • Dominant glint based prey localization in horseshoe bats: a possible strategy for noise rejection.
    Public Library of Science (PLoS), 2011
    Co-Authors: Dieter Vanderelst, Jonas Reijniers, Uwe Firzlaff, Herbert Peremans
    Abstract:

    Rhinolophidae or Horseshoe bats emit long and narrowband calls. Fluttering insect prey generates echoes in which amplitude and frequency shifts are present, i.e. glints. These glints are reliable cues about the presence of prey and also encode certain properties of the prey. In this paper, we propose that these glints, i.e. the dominant glints, are also reliable signals upon which to base prey localization. In contrast to the spectral cues used by many other bats, the localization cues in Rhinolophidae are most likely provided by self-induced amplitude modulations generated by pinnae movement. Amplitude variations in the echo not introduced by the moving pinnae can be considered as noise interfering with the localization process. The amplitude of the dominant glints is very stable. Therefore, these parts of the echoes contain very little noise. However, using only the dominant glints potentially comes at a cost. Depending on the flutter rate of the insect, a limited number of dominant glints will be present in each echo giving the bat a limited number of sample points on which to base localization. We evaluate the feasibility of a strategy under which Rhinolophidae use only dominant glints. We use a computational model of the echolocation task faced by Rhinolophidae. Our model includes the spatial filtering of the echoes by the morphology of the sonar apparatus of Rhinolophus rouxii as well as the amplitude modulations introduced by pinnae movements. Using this model, we evaluate whether the dominant glints provide Rhinolophidae with enough information to perform localization. Our simulations show that Rhinolophidae can use dominant glints in the echoes as carriers for self-induced amplitude modulations serving as localization cues. In particular, it is shown that the reduction in noise achieved by using only the dominant glints outweighs the information loss that occurs by sampling the echo

K. Christopher Beard - One of the best experts on this subject based on the ideXlab platform.

  • New chiropterans from the middle Eocene of Shanghuang (Jiangsu Province, Coastal China): new insight into the dawn horseshoe bats (Rhinolophidae) in Asia
    Zoologica Scripta, 2014
    Co-Authors: Anthony Ravel, Yuanqing Wang, K. Christopher Beard
    Abstract:

    Until recently, the fossil record of Paleogene bats in Asia primarily included extinct families (i.e. ‘Eochiroptera’) from the early Eocene of Vastan in India and from the middle-late Eocene of the Liguanqiao and Yuanqu basins in central China. Here, we describe a new fauna of Chiroptera from the middle Eocene Shanghuang fissure fillings of China. The fauna includes abundant material referred to a new rhinolophid (Protorhinolophus shanghuangensis gen. and sp. n.), one specimen of a possible rhinopomatid and several indeterminate rhinolophoids. This new bat assemblage constitutes the earliest record of extant families of microbats in Asia. Because it lacks representatives of ‘Eochiroptera’, this Shanghuang bat fauna indicates significant turnover in Asian bat communities. The dental pattern of P. shanghuangensis shows a mosaic of primitive and derived features (‘Eochiroptera’ vs Rhinolophidae dental characteristics), suggesting that this taxon occupies a basal position among the Rhinolophidae. Rhinolophids were already well diversified at the end of the late Eocene in Europe. Interestingly, many dental characteristics of Protorhinolophus are also found in a primitive rhinolophoid taxon, Vaylatsia, from the middle Eocene to late Oligocene of Europe, supporting a close relationship between these taxa. These affinities testify to the widespread Eurasian distribution of rhinolophoids during the Eocene and are consistent with a westward dispersal of the group from eastern Asia to Europe owing to the greater antiquity of Protorhinolophus.

Saheb M. - One of the best experts on this subject based on the ideXlab platform.

  • Rapid assessment of cave-dwelling bat diversity in the Chebket ES-Sellaoua Mountains (Eastern Algeria)
    Museu de Ciències Naturals de Barcelona, 2018
    Co-Authors: Mokrani Y., Mimeche F., Nouidjem Y., Saheb M.
    Abstract:

    Information about the ecology and lifestyle of bats (Chiroptera) in Algeria is scarce. In this paper, we present the results of an inventory study of Chiroptera fauna in the Chebket ES-Sellaoua Mountains in Eastern Algeria, conducted between January 2014 and December 2015. Surveys were carried out in 10 caves throughout the region by means of a visual survey and animal captures. Five species were detected: Rhinolophus ferrumequinum, Rhinolophus hipposideros, Myotis punicus, Miniopterus schreibersi and Pipistrellus kuhli, belonging to three families: Rhinolophidae, Miniopteridae and Vespertilionidae.. Data published in Mendeley (doi:10.17632/vh83vg9n9j.2)

  • Rapid assessment of cave-dwelling bat diversity in the Chebket ES-Sellaoua Mountains (Eastern Algeria)
    'Consorci del Museu de Ciencies Naturals de Barcelona', 2018
    Co-Authors: Mokrani Y., Mimeche F., Nouidjem Y., Saheb M.
    Abstract:

    Valoració ràpida de la diversitat de ratpenats que habiten les coves de les muntanyes de Chebket ES-Sellaoua (est d’Algèria) La informació sobre l’ecologia i els hàbits de vida dels ratpenats d’Algèria és molt limitada. Aquest treball recull els resultats d’un estudi destinat a inventariar la fauna de quiròpters de les muntanyes de Chebket ES-Sellaoua (est d’Algèria) entre gener de 2014 i desembre de 2015. Les prospeccions van incloure observacions visuals i captures d’espècimens. Es van identificar cinc espècies, Rhinolophus ferrumequinum, Rhinolophus hipposideros, Myotis punicus, Miniopterus schreibersi i Pipistrellus kuhli pertanyents a tres famílies, Rhinolophidae, Miniopteridae i Vespertilionidae. Dades publicades a Mendeley (doi:10.17632/vh83vg9n9j.2).Valoración rápida de la diversidad de murciélagos que habitan las cuevas de las montañas de Chebket ES-Sellaoua (este de Argelia) La información sobre la ecología y hábitos de vida de los murciélagos de Argelia es muy limitada. Este trabajo recoge los resultados de un estudio realizado para inventariar la fauna de quirópteros de las montañas de Chebket ES-Sellaoua (este de Argelia) entre enero de 2014 y diciembre de 2015. Las prospecciones incluyeron observaciones visuales y capturas de especímenes. Se identificaron cinco especies, Rhinolophus ferrumequinum, Rhinolophus hipposideros, Myotis punicus, Miniopterus schreibersi y Pipistrellus kuhli pertenecientes a tres familias, Rhinolophidae, Miniopteridae y Vespertilionidae. Datos publicados en Mendeley (doi:10.17632/vh83vg9n9j.2).Information about the ecology and lifestyle of bats (Chiroptera) in Algeria is scarce. In this paper, we present the results of an inventory study of Chiroptera fauna in the Chebket ES-Sellaoua Mountains in Eastern Algeria, conducted between January 2014 and December 2015. Surveys were carried out in 10 caves throughout the region by means of a visual survey and animal captures. Five species were detected: Rhinolophus ferrumequinum, Rhinolophus hipposideros, Myotis punicus, Miniopterus schreibersi and Pipistrellus kuhli, belonging to three families: Rhinolophidae, Miniopteridae and Vespertilionidae. Data published in Mendeley (doi:10.17632/vh83vg9n9j.2)

David S. Jacobs - One of the best experts on this subject based on the ideXlab platform.

  • High Duty Cycle Echolocation May Constrain the Evolution of Diversity within Horseshoe Bats (Family: Rhinolophidae)
    'MDPI AG', 2018
    Co-Authors: David S. Jacobs, Anna Bastian
    Abstract:

    The phenotype of organisms is the net result of various evolutionary forces acting upon their lineages over time. When an innovative trait arises that confers a substantial advantage in terms of survival and reproduction, the evolution of adaptive complexes between such an innovation and other traits may constrain diversification of that lineage. The specialized echolocation system of the Rhinolophidae may represent such an innovation which affects other parts of the phenotype. We investigated a potential constraint on the diversity of phenotypes of several species of horseshoe bats within a phylogenetic framework. If phenotypic convergence stems from stasis as a result of the specialized echolocation system, phenotypes should converge not only among members of the same species and between sexes but also among species. We analyzed the phenotypic diversity of >800 individuals of 13–16 species. The phenotypes in the horseshoe bats did indeed converge. There was no sexual size dimorphism in mass, forearm length and wingspan within species and there was marked interspecific similarity in both wing and echolocation variables but marked variability in body mass. Furthermore, correlations of wing and echolocation variables with mass suggest that variability within horseshoe bats was largely the result of selection on body size with allometric responses in wing and echolocation parameters, a potential consequence of constraints imposed by their specialized echolocation

  • testing the sensory drive hypothesis geographic variation in echolocation frequencies of geoffroy s horseshoe bat Rhinolophidae rhinolophus clivosus
    PLOS ONE, 2017
    Co-Authors: David S. Jacobs, Gregory L Mutumi, Sarah Catto, Nikita Finger, Paul W Webala
    Abstract:

    Geographic variation in sensory traits is usually influenced by adaptive processes because these traits are involved in crucial life-history aspects including orientation, communication, lineage recognition and mate choice. Studying this variation can therefore provide insights into lineage diversification. According to the Sensory Drive Hypothesis, lineage diversification may be driven by adaptation of sensory systems to local environments. It predicts that acoustic signals vary in association with local climatic conditions so that atmospheric attenuation is minimized and transmission of the signals maximized. To test this prediction, we investigated the influence of climatic factors (specifically relative humidity and temperature) on geographic variation in the resting frequencies of the echolocation pulses of Geoffroy’s horseshoe bat, Rhinolophus clivosus. If the evolution of phenotypic variation in this lineage tracks climate variation, human induced climate change may lead to decreases in detection volumes and a reduction in foraging efficiency. A complex non-linear interaction between relative humidity and temperature affects atmospheric attenuation of sound and principal components composed of these correlated variables were, therefore, used in a linear mixed effects model to assess their contribution to observed variation in resting frequencies. A principal component composed predominantly of mean annual temperature (factor loading of -0.8455) significantly explained a proportion of the variation in resting frequency across sites (P < 0.05). Specifically, at higher relative humidity (around 60%) prevalent across the distribution of R. clivosus, increasing temperature had a strong negative effect on resting frequency. Climatic factors thus strongly influence acoustic signal divergence in this lineage, supporting the prediction of the Sensory Drive Hypothesis. The predicted future increase in temperature due to climate change is likely to decrease the detection volume in echolocating bats and adversely impact their foraging efficiency.

  • A rticle Fast T rack How and Why Overcome the Impediments to Resolution: Lessons from rhinolophid and hipposiderid Bats
    2016
    Co-Authors: Nicole M. Foley, David S. Jacobs, Steven M. Goodman, Sébastien J. Puechmaille, Vu Dinh Thong, Pipat Soisook, Kyle N. Armstrong, Emma C. Teeling
    Abstract:

    The phylogenetic and taxonomic relationships among the Old World leaf-nosed bats (Hipposideridae) and the closely related horseshoe bats (Rhinolophidae) remain unresolved. In this study, we generated a novel approximately 10-kb molecular data set of 19 nuclear exon and intron gene fragments for 40 bat species to elucidate the phylogenetic relationships within the families Rhinolophidae and Hipposideridae. We estimated divergence times and explored po-tential reasons for any incongruent phylogenetic signal. We demonstrated the effects of outlier taxa and genes on phylogenetic reconstructions and compared the relative performance of intron and exon data to resolve phylogenetic relationships. Phylogenetic analyses produced a well-resolved phylogeny, supporting the familial status of Hipposideridae and demonstrated the paraphyly of the largest genus, Hipposideros. A fossil-calibrated timetree and biogeographical analyses estimated that Rhinolophidae and Hipposideridae diverged in Africa during the Eocene approximately 42 Ma. The phylogram, the timetree, and a unique retrotransposon insertion supported the elevation of the subtribe Rhinonycterina to family level and which is diagnosed herein. Comparative analysis of diversification rates showe

  • A rticle How and Why Overcome the Impediments to Resolution: Lessons from rhinolophid and hipposiderid Bats
    2016
    Co-Authors: Nicole M. Foley, David S. Jacobs, Steven M. Goodman, Sébastien J. Puechmaille, Vu Dinh Thong, Pipat Soisook, Kyle N. Armstrong, Emma C. Teeling
    Abstract:

    The phylogenetic and taxonomic relationships among the Old World leaf-nosed bats (Hipposideridae) and the closely related horseshoe bats (Rhinolophidae) remain unresolved. In this study, we generated a novel approximately 10-kb molecular data set of 19 nuclear exon and intron gene fragments for 40 bat species to elucidate the phylogenetic relationships within the families Rhinolophidae and Hipposideridae. We estimated divergence times and explored po-tential reasons for any incongruent phylogenetic signal. We demonstrated the effects of outlier taxa and genes on phylogenetic reconstructions and compared the relative performance of intron and exon data to resolve phylogenetic relationships. Phylogenetic analyses produced a well-resolved phylogeny, supporting the familial status of Hipposideridae and demonstrated the paraphyly of the largest genus, Hipposideros. A fossil-calibrated timetree and biogeographical analyses estimated that Rhinolophidae and Hipposideridae diverged in Africa during the Eocene approximately 42 Ma. The phylogram, the timetree, and a unique retrotransposon insertion supported the elevation of the subtribe Rhinonycterina to family level and which is diagnosed herein. Comparative analysis of diversification rates showe

  • Bayesian consensus topology of Rhinolophus spp. based on cytochrome b.
    2013
    Co-Authors: David S. Jacobs, Anna Bastian, Hassan Babiker, Teresa Kearney, Rowen Van Eeden, Jacqueline M. Bishop
    Abstract:

    Values above nodes indicate Bayesian posterior probabilities (> 0.80) and below nodes report parsimony bootstrap support. Branch lengths are proportional to average number of substitutions per site. Divergence times (millions years ago, Mya) were estimated for three nodes of interest: node A = 4.8 Mya (95% HPD; 2.69–7.52), B = 9.68 Mya (95% HPD; 5.87–10.04), C = 10.51 Mya (95% HPD; 6.65–15.43). The split between the Hipposideridae (outgroup) and the Rhinolophidae together with fossil dates for R. ferrumequinum were used as calibration points; calibration points are indicated on the tree with an asterisk *. Sequences from the type localities for R. darlingi darlingi (TM2476) and R. darlingi damarensis (TM9474) are indicated on the tree in bold. The eastern R. darlingi darlingi subspecies forms a single clade together with R. fumigatus, R. eloquens and R. hildebrandti (blue) while R. damarensis damarensis, distributed in the western region of southern Africa, is composed of two very well supported clades that subdivide into northern and southern lineages (red) that diverged in the late Miocene.

Koubínová Darina - One of the best experts on this subject based on the ideXlab platform.

  • Fylogeneze vybraných druhů letounů Afriky na základě cytogenetického a molekulárního přístupu
    Univerzita Karlova Přírodovědecká fakulta, 2013
    Co-Authors: Koubínová Darina
    Abstract:

    Fylogenetické vztahy byly zkoumány ve vzorku obsahujícím 248 netopýrů patřících do 19 druhů a čtyř čeledí (Hipposideridae, Rhinolophidae, Molossidae a Vespertilionidae) ze Senegalu (západní Afriky) s použitím multilokusových sekvenčních dat a nediferenciálně obarvených chromosomů. Karyotypy Hipposideros ruber, H. tephrus, H. jonesi a H. cyclops byly popsány poprvé. Standardní formule rodu Hipposideros byla zaznamenána u H. tephrus, H. jonesi a H. ruber (2n = 32, FNa = 60, FN = 64). Karyotypy H. cyclops (2n = 36, FN = 66) a H. gigas (2n = 52, FN = 64) se nápadně lišily od této typické chromosomální sady. Rhinolophus landeri a R. fumigatus měli shodný diploidní počet chromosomů (2n = 58), ale lišili se jejich morfologií (R. fumigatus - FNa = 60, FN = 64; R. landeri - FNa = 64, FN = 68). Rhinolophus landeri se karyotypově odlišoval od ostatních afrických populací, což může signalizovat přítomnost kryptických forem v rámci tohoto druhu. Karyotypy Chaerephon pumilus a Mops condylurus obsahovaly 48 chromosomů (FN = 54), což odpovídá standardní sadě nalézané u příslušníků této čeledi. Chromosomy, Bayesiánské metody, maximální pravděpodobnost a analýza genetických distancí naznačily existenci kryptických forem u pěti z deseti vyšetřených druhů západoafrických vespertilionidních netopýrů - Pipistrellus...Phylogenetic relationships of a sample comprising 248 bats belonging to 19 species and four families (Hipposideridae, Rhinolophidae, Molossidae and Vespertilionidae) from Senegal (Western Africa) were investigated with the use of multi-locus sequence data and non- differentially stained chromosomes. The karyotypes of Hipposideros ruber, H. tephrus, H. jonesi and H. cyclops were described for the first time. The standard Hipposideros formula was recorded in H. tephrus, H. jonesi and H. ruber (2n = 32, FNa = 60, FN = 64). The karyotypes of H. cyclops (2n = 36, FN = 66) and H. gigas (2n = 52, FN = 64) substantially diverged from this typical chromosomal complement. Rhinolophus landeri and R. fumigatus shared the same diploid number (2n = 58), but differed in the chromosome morphology (R. fumigatus - FNa = 60, FN = 64; R. landeri - FNa = 64, FN = 68). Rhinolophus landeri was found karyotypically distinct to other African populations, thus signalling a possible presence of cryptic forms within this species. The karyotypes of Chaerephon pumilus and Mops condylurus had a 2n = 48, FN = 54 and were similar to other previously studied species of this chromosomally conservative family. Chromosomal, Bayesian, maximum likelihood and genetic distance analyses revealed an indication for the existence of cryptic...Katedra zoologieDepartment of ZoologyPřírodovědecká fakultaFaculty of Scienc

  • Fylogeneze vybraných druhů letounů Afriky na základě cytogenetického a molekulárního přístupu
    2013
    Co-Authors: Koubínová Darina
    Abstract:

    Phylogenetic relationships of a sample comprising 248 bats belonging to 19 species and four families (Hipposideridae, Rhinolophidae, Molossidae and Vespertilionidae) from Senegal (Western Africa) were investigated with the use of multi-locus sequence data and non- differentially stained chromosomes. The karyotypes of Hipposideros ruber, H. tephrus, H. jonesi and H. cyclops were described for the first time. The standard Hipposideros formula was recorded in H. tephrus, H. jonesi and H. ruber (2n = 32, FNa = 60, FN = 64). The karyotypes of H. cyclops (2n = 36, FN = 66) and H. gigas (2n = 52, FN = 64) substantially diverged from this typical chromosomal complement. Rhinolophus landeri and R. fumigatus shared the same diploid number (2n = 58), but differed in the chromosome morphology (R. fumigatus - FNa = 60, FN = 64; R. landeri - FNa = 64, FN = 68). Rhinolophus landeri was found karyotypically distinct to other African populations, thus signalling a possible presence of cryptic forms within this species. The karyotypes of Chaerephon pumilus and Mops condylurus had a 2n = 48, FN = 54 and were similar to other previously studied species of this chromosomally conservative family. Chromosomal, Bayesian, maximum likelihood and genetic distance analyses revealed an indication for the existence of cryptic..