environmental conditions favoring bat infection with histoplasma capsulatum in mexican shelters.histoplasma capsulatum was isolated from gut, lung, liver, and spleen of 17 of 208 captured bats belonging to 6 different genera and species. three of the 17 infected bats were from the state of guerrero and 14 were from the state of morelos. all were adult bats: 6 males (1 pteronotus parnellii, 2 natalus stramineus, 2 artibeus hirsutus, and 1 leptonycteris nivalis) and 11 females (1 myotis californicus, 1 mormoops megalophylla, 8 a. hirsutus, and 1 l. nivalis). high rates of bat infection with ...199910674670
genome sequence analysis of tamana bat virus and its relationship with the genus flavivirus.tamana bat virus (tabv, isolated from the bat pteronotus parnellii) is currently classified as a tentative species in the genus flavivirus: we report here the determination and analysis of its complete coding sequence. low but significant similarity scores between tabv and member-viruses of the genus flavivirus were identified in the amino acid sequences of the structural, ns3 and ns5 genes. a series of cysteines located in the envelope protein and the most important enzymatic domains of the vir ...200212237426
dengue virus in mexican bats.individuals belonging to five families, 12 genera, and 19 different species of bats from dengue endemic areas in the gulf and pacific coasts of mexico were examined by elisa, rt-pcr, and for the presence of dengue virus (dv) ns1 protein. nine individuals from four species were seropositive by elisa: three insectivorous, myotis nigricans (four positives/12 examined), pteronotus parnellii (3/19), and natalus stramineus (1/4), and one frugivorous artibeus jamaicensis (1/35) (12.86% seroprevalence i ...200818325131
cochlear and cns tonotopy: normal physiological shifts in the mustached bat.the ear of the mustached bat (pteronotus parnellii) shows marked cochlear resonance near 60 khz and many sharply tuned neurons throughout the brain have best frequencies (bf) near the cochlear resonance frequency (crf). controlled changes in the normal physiological range of body temperature (approx 37-42 degrees c) were used to change the crf and to study the tuning properties of neurons in the cochlear nucleus (cn) and inferior colliculus (ic). in all cases there were concomitant shifts in the ...20031769926
sylvatic focus of american trypanosomiasis in the state of morelos, mexico.wild vectors and reservoir hosts of trypanosoma cruzi were surveyed from february 1993 to june 1994 in ticumán (18 degrees 46'n, 99 degrees 07'w), mexico (deciduous tropical forest). direct faeces examination showed that 87% of triatoma pallidipennis hosted the parasite; t. cruzi forms were present in cultures inoculated with faeces of fifty 67% triatomine bugs and thirty cd-1 strain mice (10 d old) inoculated (peritoneum) with faeces of positive insects t. cruzi amastigotes were found in heart ...200111935921
plasticity of the cochleotopic (frequency) map in specialized and nonspecialized auditory cortices.auditory conditioning (associative learning) causes reorganization of the cochleotopic (frequency) maps of the primary auditory cortex (ai) and the inferior colliculus. focal electric stimulation of the ai also evokes basically the same cortical and collicular reorganization as that caused by conditioning. therefore, part of the neural mechanism for the plasticity of the central auditory system caused by conditioning can be explored by focal electric stimulation of the ai. the reorganization is ...200111248108
projections of physiologically defined subdivisions of the inferior colliculus in the mustached bat: targets in the medial geniculate body and extrathalamic nuclei.this study examined the output of the central nucleus of the inferior colliculus to the medial geniculate body and other parts of the nervous system in the mustached bat (pteronotus parnellii). small deposits of anterograde tracers (horseradish peroxidase, [3h]leucine, phaseolus vulgaris leucoagglutinin, wheat germ agglutinin conjugated to horseradish peroxidase, or biocytin) were made at physiologically defined sites in the central nucleus representing major components of the bat's echolocation ...19947962717
patterns of gabaergic immunoreactivity define subdivisions of the mustached bat's medial geniculate body.the anatomy and the spatial distribution of neurons and axonal endings (puncta) immunoreactive for glutamic acid decarboxylase (gad) or gamma-aminobutyric acid (gaba) were studied in the medial geniculate body of the mustached bat (pteronotus parnellii). the principal findings are that: 1) most gabaergic neurons are present in the dorsal and ventral divisions with few, if any, in the medial division; 2) only a small fraction, about 1% or less, of auditory thalamic neurons are immunopositive; 3) ...19921592903
blurry topography for precise target-distance computations in the auditory cortex of echolocating bats.echolocating bats use the time from biosonar pulse emission to the arrival of echo (defined as echo delay) to calculate the space depth of targets. in the dorsal auditory cortex of several species, neurons that encode increasing echo delays are organized rostrocaudally in a topographic arrangement defined as chronotopy. precise chronotopy could be important for precise target-distance computations. here we show that in the cortex of three echolocating bat species (pteronotus quadridens, pteronot ...201324107903
mapping of the auditory area in the cerebellar vermis and hemispheres of the mustache bat, pteronotus parnellii parnellii.microelectrode mapping of the auditory areas in the cerebellar vermis and hemispheres of mustache bats, pteronotus parnellii parnellii, reveals that a large area of the bat's cerebellum contains units responding to acoustic signals. a study of frequency tuning of isolated units shows that there are two large groups of auditory units. the units of one group are sharply tuned to a very narrow band of frequency with bfs between 60 and 64 khz. the units of the other group are broadly tuned, with bfs ...19836349748
projection to the inferior colliculus from the basal nucleus of the amygdala.this report describes a projection from the amygdala, a forebrain center mediating emotional expression, to the inferior colliculus (ic), the midbrain integration center of the ascending auditory system. in the ic of mustached bats (pteronotus parnellii) and pallid bats (antrozous pallidus), we placed deposits of retrograde tracers at physiologically defined sites and then searched for retrogradely labeled somata in the forebrain. labeling was most sensitive in experiments using cholera toxin b- ...200212451144
unique loss of the pyhin gene family in bats amongst mammals: implications for inflammasome sensing.recent genomic analysis of two bat species (pteropus alecto and myotis davidii) revealed the absence of the pyhin gene family. this family is recognized as important immune sensors of intracellular self and foreign dna and activators of the inflammasome and/or interferon pathways. further assessment of a wider range of bat genomes was necessary to determine if this is a universal pattern for this large mammalian group. here we expanded genomic analysis of this gene family to include ten bat spec ...201626906452
litomosoides yutajensis n. sp., first record of this filarial genus in a mormoopid bat.twenty-five bats were trapped in yutaje (amazonas, venezuela) and examined for litomosoides (filarioidea: onchocercidae). of the nine recovered bat species, only pteronotus parnelli was infected; it is a cave-dwelling species belonging to a family, mormoopidae, which has not previously been included in the host range of the genus. the new species, l. yutajensis n. sp., has two median cephalic bosses covered with rugosities and differs from the 15 recognized species and subspecies from bats in se ...200314535161
high duty cycle to low duty cycle: echolocation behaviour of the hipposiderid bat coelops frithii.laryngeally echolocating bats avoid self-deafening (forward masking) by separating pulse and echo either in time using low duty cycle (ldc) echolocation, or in frequency using high duty cycle (hdc) echolocation. hdc echolocators are specialized to detect fluttering targets in cluttered environments. hdc echolocation is found only in the families rhinolophidae and hipposideridae in the old world and in the new world mormoopid, pteronotus parnellii. here we report that the hipposiderid coelops fri ...201323717396
auditory responses from the frontal cortex in the mustached bat, pteronotus parnellii.response properties of neurons in an auditory field in the frontal cortex of the mustached bat, pteronotus parnellii, have not been studied before. we recorded neural responses to constant frequency (cf) stimuli from the frontal auditory field in awake animals. the majority (75%) of neurons in this area responded well and often exhibited low thresholds to cf stimuli. most cf-responsive neurons exhibited sharp tuning with values of > 180 for q10db, a quality factor expressing the sharpness of tun ...200010674488
syntax processing by auditory cortical neurons in the fm-fm area of the mustached bat pteronotus parnellii.syntax denotes a rule system that allows one to predict the sequencing of communication signals. despite its significance for both human speech processing and animal acoustic communication, the representation of syntactic structure in the mammalian brain has not been studied electrophysiologically at the single-unit level. in the search for a neuronal correlate for syntax, we used playback of natural and temporally destructured complex species-specific communication calls-so-called composites-wh ...19979391145
origin of ascending projections to inferior colliculus in the mustache bat, pteronotus parnellii.the origins of pathways to the inferior colliculus of the mustache bat were identified by retrograde transport of horseradish peroxidase (hrp). a specific goal of this study was to obtain evidence that would help determine whether the nuclei, shown in the previous paper to have unusual cytoarchitectural features, are unique to bats, or whether they are homologous to areas that are not well differentiated in other mammals. the auditory pathways in the lower brain stem of pteronotus appear to conf ...19827096636
distribution of catecholamine fibers in the cochlear nucleus of horseshoe bats and mustache bats.the glyoxylic-acid-induced fluorescence technique was applied to demonstrate patterns of catecholaminergic innervation within the auditory brainstem of echolocating bats and the house mouse. in the cochlear nucleus of the rufous horseshoe bat (rhinolophus rouxi) and the mustache bat (pteronotus parnellii), species-specific catecholaminergic innervation patterns are found that contrast with the relatively homogeneous innervation in the rodent. in both bats the subnuclei of the cochlear nucleus re ...19883372726
delay-tuned neurons in auditory cortex of mustached bat are not suited for processing directional information.1. the mustached bat, pteronotus parnellii parnellii, emits bisonar pulses each consisting of eight components: cf1-4 and fm1-4. in the auditory cortex of the bat there are arrays of fm-fm neurons that are tuned to particular delays of echo fmn (n = 2, 3, or 4) from pulse fm1. they are specialized for the processing of target-range information. the fm signal is suited for ranging and also for target localization. therefore we studied the directional sensitivity of fm-fm neurons with pulse fm1 an ...19902388067
projections to the medial superior olive from the medial and lateral nuclei of the trapezoid body in rodents and this study we present direct evidence of axonal projections from both the medial and lateral nuclei of the trapezoid body to the medial superior olive. projections were traced by intracellularly labeling cells and axons in a tissue slice preparation of two rodent species, mus musculus and meriones unguiculatus and two bat species, eptesicus fuscus and pteronotus parnellii. the main axon of most principal cells in the medial nucleus of the trapezoid body gives off one or more collateral branch ...19921430335
effects of anthropogenic disturbance and climate on patterns of bat fly parasitism.environmental conditions, including anthropogenic disturbance, can significantly alter host and parasite communities. yet, our current knowledge is based mainly on endoparasites, while ectoparasites remain little studied. we studied the indirect effects of anthropogenic disturbance (human population density) and climate (temperature, precipitation and elevation) on abundance of highly host-specific bat flies in four neotropical bat species across 43 localities in venezuela. we formulated a set o ...201222829953
connections and frequency representation in the auditory brainstem of the mustache bat, pteronotus parnellii.the goals of this study were to describe the cochlear frequency map of the mustache bat, pteronotus parnellii, and to relate the organization of cochlear primary afferents to that of the second-order projections from the cochlear nucleus to the superior olivary complex. small deposits of horseradish peroxidase (hrp) were placed in the cochlear nucleus at sites that were physiologically characterized with respect to unit-best frequency. from the deposits, labeled fibers were traced in the retrogr ...19892592612
diversity of bats trypanosomes in hydroeletric area of belo monte in brazilian amazonia.the trypanosoma comprises flagellates able to infect many mammalian species and is transmitted by several groups of invertebrates. the order chiroptera can be infected by the subgenera herpetosoma, schizotrypanum, megatrypanum and trypanozoon. in this study, we described the diversity of bats trypanosomes, inferring the phylogenetic relationships among the trypanosomes from bats caught belo monte hydroeletric area (brazilian amazonia). trypanosomes from bats were isolated by haemoculture, and th ...201627633579
trypanosoma cruzi and leishmania infantum chagasi infection in wild mammals from maranhão state, brazil.trypanosoma and leishmania are obligate parasites that cause important diseases in human and domestic animals. wild mammals are the natural reservoirs of these parasites, which are transmitted by hematophagous arthropods. the present study aimed to detect the natural occurrence of trypanosomatids through serological diagnosis, pcr of whole blood and blood culture (hemoculture), and phylogenetic relationships using small subunit ribosomal dna (ssu rdna), cytochrome b, and glycosomal glyceraldehyd ...201526501369
properties of echo delay-tuning receptive fields in the inferior colliculus of the mustached role of the inferior colliculus (ic) in bats is to create neuronal delay-tuning, which is used for the estimation of target distance in the echolocating bat's auditory system. in this study, we describe response properties of ic delay-tuned neurons of the mustached bat (pteronotus parnellii) and compare it with those of delay-tuned neurons of the auditory cortex (ac). we also address the question if frequency content of the stimulus (pure-tone (pt) or frequency-modulated (fm) pairs stimulati ...201222446180
evoked acoustic emissions and cochlear microphonics in the mustache bat, pteronotus the echolocating bat, pteronotus parnellii, otoacoustic responses at a frequency of 62 khz are measurable in the external ear canal during continuous and after transient acoustic stimulation. these responses are interpreted to represent emissions from the cochlea. they can reach an amplitude as large as 70 db spl and occur in the frequency range most important for echolocation, namely on the average about 700 hz above the constant frequency component of the orientation calls. a sharp maximum ...20144055535
topographic representation of vocal frequency demonstrated by microstimulation of anterior cingulate cortex in the echolocating bat, pteronotus parnelli parnelli.1. a midline region of brain dorsal and anterior to the corpus callosum, presumably anterior cingulate cortex, has been explored for its role in the production of vocalization in the mustached bat, pteronotus p. parnelli. 2. vocalizations elicited by microstimulation were virtually indistinguishable from natural biosonar sounds. the spectral content, relative intensity of harmonic components, and durations of emitted pulses are comparable to spontaneous emissions. 3. the frequencies of elicited ...20133625577
the cochlear frequency map of the mustache bat, pteronotus parnellii.the frequency-place map of the cochlea of mustache bats was constructed by the analysis of hrp-transport patterns in spiral ganglion cells following iontophoretic tracer injections into cochlear nucleus regions responsive to different frequencies. the cochlea consists of 5 half turns (total length 14.3 mm) and the representation of certain frequency bands can be assigned to specific cochlear regions: the broad high frequency range between 70 and 111 khz is represented in the most basal half turn ...20133837108
basolateral amygdala responds robustly to social calls: spiking characteristics of single unit activity.vocalizations emitted within a social context can trigger call-specific changes in the emotional and physiological/autonomic state of the receiver. the amygdala is implicated in mediating these changes, but its role in call perception remains relatively unexplored. we examined call and pitch selectivity of single neurons within the basolateral amygdala (bla) by recording spiking activity in response to 5 pitch variants of each of 14 species-specific calls presented to awake, head-restrained must ...201121368003
monaural interaction of excitation and inhibition in the medial superior olive of the mustached bat: an adaptation for most mammals, the superior olive is the first stage for binaural interaction. neurons in the medial superior olive (mso) receive excitatory input from both ears and are sensitive to interaural time or phase differences of low-frequency sounds. the mustached bat (pteronotus parnellii parnellii), a small echolocating species with high-frequency hearing, probably does not use interaural time or phase differences as cues for sound localization. although the mustached bat has a large mso, there is ...20061594619
postnatal maturation of primary auditory cortex in the mustached bat, pteronotus parnellii.the primary auditory cortex (ai) of adult pteronotus parnellii features a foveal representation of the second harmonic constant frequency (cf2) echolocation call component. in the corresponding doppler-shifted constant frequency (dscf) area, the 61 khz range is over-represented for extraction of frequency-shift information in cf2 echoes. to assess to which degree ai postnatal maturation depends on active echolocation or/and reflects ongoing cochlear maturation, cortical neurons were recorded in ...201020181735
doppler-shift compensation behavior by wagner's mustached bat, pteronotus personatus.doppler-shift compensation behavior (dsc) is a highly specialized vocal response displayed by bats that emit pulses with a prominent constant frequency (cf) component and adjust the frequency of their cf component to compensate for flight-speed induced doppler shifts in the frequency of the returning echoes. dsc has only been observed in one member of the neotropical mormoopidae, a family of bats that use pulses with prominent cf components, leading researchers to suspect that dsc is a uniquely ...200818537384
effect of captivity and mineral supplementation on body composition and mineral status of mustached bats (pteronotus parnellii rubiginosus).we investigated the whole-body crude nutrient (fat, protein, ash) and mineral (ca, p, mg, na, k) composition of mustached bats of three different groups: animals from the wild (n = 6), and animals from captivity on an unsupplemented feeding regime of mealworms (n = 7), and on a feeding regime in which the mealworms were kept on a mineral substrate prior to feeding (n = 6). it was shown that mealworms from the mineral substrate had higher ca contents than mealworms from the conventional substrate ...200717516939
directionality of hearing in two cf/fm bats, pteronotus parnellii and rhinolophus rouxi.the head-related transfer function (hrtf) has been measured in two cf/fm bats, pteronotus parnellii and rhinolophus rouxi from 575 positions in the frontal hemisphere. p. parnellii showed an increase of the elevation angle of the axis of highest pinna gain with increasing frequency followed by a specific decrease at 75 khz. such a drop of elevation angle of the acoustic axis was not seen in r. rouxi. the hrtf further showed a spectral notch dependent on elevation and frequency in p. parnellii, b ...200415504606
is humanlike cytoarchitectural asymmetry present in another species with complex social vocalization? a stereologic analysis of mustached bat auditory cortex.considerable evidence suggests that left hemispheric lateralization for language comprehension in humans is associated with cortical microstructural asymmetries. however, despite the fact that left hemispheric dominance for the analysis of species-specific social vocalizations has been reported in several other species, little is known concerning microstructural asymmetries in auditory cortex of nonhumans. to test whether such neuroanatomical lateralization characterizes another species with com ...200515910775
testing the hindlimb-strength hypothesis: non-aerial locomotion by chiroptera is not constrained by the dimensions of the femur or the evolution of flight bats appear to have suffered a trade-off; they have become poor crawlers relative to terrestrial mammals. capable walking does occur in a few disparate taxa, including the vampire bats, but the vast majority of bats are able only to shuffle awkwardly along the ground, and the morphological bases of differences in crawling ability are not currently understood. one widely cited hypothesis suggests that the femora of most bats are too weak to withstand the compressive for ...200515781891
local field potentials and spiking activity in the primary auditory cortex in response to social calls.the mustached bat, pteronotus parnellii, uses complex communication sounds ("calls") for social interactions. we recorded both event-related local field potentials (lfps) and single/few-unit (su) spike activity from the same electrode in the posterior region of the primary auditory cortex (aip) during presentation of simple syllabic calls to awake bats. temporal properties of the lfps, which reflect activity within local neuronal clusters, and spike discharges from sus were studied at 138 record ...200415212439
what ears do for bats: a comparative study of pinna sound pressure transformation in chiroptera.using a moveable loudspeaker and an implanted microphone, we studied the sound pressure transformation of the external ears of 47 species of bats from 13 families. we compared pinna gain, directionality of hearing and interaural intensity differences (iid) in echolocating and non-echolocating bats, in species using different echolocation strategies and in species that depend upon prey-generated sounds to locate their targets. in the pteropodidae, two echolocating species had slightly higher dire ...19938371084
the development of a single frequency place in the mammalian cochlea: the cochlear resonance in the mustached bat pteronotus parnellii.cochlear microphonic potentials (cms) were recorded from the sharply tuned, strongly resonant auditory foveae of 1- to 5-week-old mustached bats that were anesthetized with rompun and ketavet. the fovea processes doppler-shifted echo responses of the constant-frequency component of echolocation calls. during development, the frequency and tuning sharpness of the cochlear resonance increases, and cm ringing persists for longer after the tone. cm is relatively insensitive at tone onset and grows l ...200314645493
volumetric comparison of the accessory olfactory bulb in bats.accessory olfactory bulb (aob) volumes were calculated in 26 chiropteran species. the percentage of the aob in relation to the olfactory bulb complex ranges between 0.18 and 2.70%. the allometric comparison reveals the high development of this structure in the phyllostomatid subfamily of glossophaginae. carolliinae and sturnirinae are near the chiropteran average. smaller aobs can be observed in sphaeronycteris, diphylla, pteronotus parnellii and miniopterus schreibersi. comparison of the right/ ...19817246042
intercellular material in the basal and lateral folds of parotid serous cells in four species of bats.basal folds are slender plications at the basal surface of acinar cells in the salivary glands of many mammalian species. these largely organelle-free folds increase the surface area of the basal plasmalemma manyfold and are unquestionably involved in the translocation of organic and inorganic molecules and water into the acinar cells.19989605223
oxytocin within auditory nuclei: a neuromodulatory function in sensory processing?oxytocin (ot) plays an important role in social bonding, ultrasonic vocalizations and other sexual behaviors in mammalian species. although its presence within neuroendocrine regions in the forebrain is well established, its association with sensory nuclei remains unclear. we report here the presence of oxytocin immunoreactive neurons within several nuclei in the auditory brain stem of the mustached bat, pteronotus parnellii. immunocytochemical procedures revealed ot-immunoreactive perikarya and ...200212488795
variations in respiratory muscle activity during echolocation when stationary in three species of bat (microchiroptera: vespertilionidae).echolocating bats use respiratory muscles to power the production of biosonar vocalisations. the physical characteristics of these calls vary among species of bat, and variations also exist in the timing and patterns of respiratory muscle recruitment during echolocation. we recorded electromyograms from the respiratory muscles of three species of bat (family vespertilionidae) while the animals vocalised from stationary positions. activity was recorded consistently from the lateral abdominal musc ...200111815644
evolution of neuronal mechanisms for echolocation: specializations for target-range computation in bats of the genus pteronotus.delay tuning was studied in the auditory cortex of pteronotus quadridens. all the 136 delay-tuned units that were studied responded strongly to heteroharmonic pulse-echo pairs presented at specific delays. in the heteroharmonic pairs, the first sonar call harmonic marks the timing of pulse emission while one of the higher harmonics (second or third) indicates the timing of the echo. delay-tuned units are organized chronotopically along a rostrocaudal axis according to their characteristic delay. ...201323297928
multiple combination-sensitive neurons in the auditory cortex of the mustached bat.the mustached bat, pteronotus parnellii, emits biosonar pulses consisting of four constant-frequency (cf(1-4)) and four frequency-modulated (fm(1-4)) components. the fm-fm area of its auditory cortex consists of three subdivisions, containing either fm(1)-fm(2), fm(1)-fm(3) or fm(1)-fm(4) combination-sensitive neurons. the fm-fm area also contains 'multiple combination-sensitive' neurons: fm(1)-fm(2,3), fm(1)-fm(3,4), fm(1)-fm(2,4), and fm(1)-fm(2,3,4) neurons. all fm-fm neurons are tuned to a t ...200111124448
simple syllabic calls accompany discrete behavior patterns in captive pteronotus parnellii: an illustration of the motivation-structure hypothesis.mustached bats, pteronotus parnellii, are highly social and vocal. individuals of this species roost in tight clusters, and emit an acoustically rich repertoire of calls whose behavioral significance is largely unknown. we recorded their social and vocal behaviors within a colony housed under semi-natural conditions. we also quantified the spatial spread of each bat's roosting location and discovered that this was relatively fixed and roughly confined to an individual's body width. the spatial p ...201222693429
anatomical and functional imaging of the auditory cortex in awake mustached bats using magnetic resonance technology.the auditory cortex of mustached bats, pteronotus parnellii, has been studied extensively using neuroanatomical tract-tracing and electrophysiological techniques to elucidate the functional organization and neural mechanisms important for auditory processing. while these techniques have identified several cortical maps involved in processing auditory information, there has been no direct observation of the dynamics of simultaneous activation of several discrete areas. we applied magnetic resonan ...199910592345
selectivity and persistent firing responses to social vocalizations in the basolateral amygdala.this study examined responsiveness to acoustic stimuli among neurons of the basolateral amygdala. while recording from single neurons in awake mustached bats (pteronotus parnellii), we presented a wide range of acoustic stimuli including tonal, noise, and vocal signals. while many neurons displayed phasic or sustained responses locked to effective auditory stimuli, the majority of neurons (n=58) displayed a persistent excitatory discharge that lasted well beyond stimulus duration and filled the ...201222569154
resource partitioning by insectivorous bats in this investigation, we use variation in wing morphology, echolocation behaviour, patterns of habitat use and molecular diet analysis to demonstrate that six species of sympatric insectivorous bats in jamaica show significant differences that could explain resource partitioning among the species. high-intensity echolocating species that used shorter, broadband signals and had shorter, broader wings (pteronotus macleayii, pteronotus quadridens, mormoops blainvillii) foraged most in edge habitat ...201425187923
right-left asymmetry in the cortical processing of sounds for social communication vs. navigation in mustached the doppler-shifted constant frequency processing area in the primary auditory cortex of mustached bats, pteronotus parnellii, neurons respond to both social calls and to echolocation signals. this multifunctional nature of cortical neurons creates a paradox for simultaneous processing of two behaviorally distinct categories of sound. to test the possibility of a stimulus-specific hemispheric bias, single-unit responses were obtained to both types of sounds, calls and pulse-echo tone pairs, f ...201222211945
ectoparasitic assemblages on mormoopid bats (chiroptera: mormoopidae) from puerto rico.we performed the first quantitative survey of ectoparasitic assemblages on three species of mormoopid bats living on the caribbean island of puerto rico: mormoops blainvillii leach (n=40), pteronotus quadridens gundlach (n=40), and pteronotus parnellii gray (n=9). we examined bats for parasites primarily on 8-10 may and 24-27 july 2002 at culebrones cave, near arecibo, puerto rico. only 50% of m. blainvillii were infested with at least one parasite, compared with 85-100% for pteronotus; infested ...200718047193
the interhaemal barrier in the chorioallantoic placenta of the greater mustache bat, pteronotus parnellii, with observations on amplification of its intrasyncytial lamina.chorioallantoic placentae were obtained from a reproductively synchronized wild population of greater mustache bats for ultrastructural and immunocytochemical examination. the single discoidal placenta was always located in a lateral to mesometrial position on the right side of the uterus, which in the non-pregnant state is partially bicornuate. the placenta was labyrinthine and haemodichorial in advanced pregnancy. the interhaemal barrier included syncytiotrophoblast that lined the maternal vas ...20079699960
prestin shows divergent evolution between constant frequency echolocating bats.the gene prestin encodes a motor protein that is thought to confer the high-frequency sensitivity and selectivity that characterizes the mammalian auditory system. recent research shows that the prestin gene has undergone a burst of positive selection on the ancestral branch of the old world horseshoe and leaf-nosed bats (rhinolophidae and hipposideridae, respectively), and also on the branch leading to echolocating cetaceans. moreover, these two groups share a large number of convergent amino a ...201121947331
the distribution of gaba and glycine immunostaining in the cochlear nucleus of the mustached bat (pteronotus parnellii).the distribution of neuronal elements immunoreactive for gamma-aminobutyric acid (gaba) and glycine in the cochlear nucleus of the mustached bat pteronotus parnellii has been studied by means of the postembedding technique on serial semithin sections. our goal has been to identify similarities and differences in the organization of putatively inhibitory circuits between a highly specialized echolocating bat and previously studied non-echolocating mammals. the results reveal a basically conserved ...19979023080
duration tuning in the inferior colliculus of the mustached bat.we studied duration tuning in neurons of the inferior colliculus (ic) of the mustached bat. duration-tuned neurons in the ic of the mustached bat fall into three main types: short (16 of 136), band (34 of 136), and long (29 of 136) pass. the remaining 51 neurons showed no selectivity for the duration of sounds. the distribution of best durations was double peaked with maxima around 3 and 17 ms, which correlate with the duration of the short frequency-modulated (fm) and the long constant-frequenc ...201121917994
combination-sensitive neurons in the inferior colliculus.we examined whether neurons in the inferior colliculus of the mustached bat (pteronotus parnellii) are combination sensitive, responding to both low- and high-frequency components of the bat's sonar signal. these neurons, previously reported in the thalamus and cortex, analyze sonar target features including distance. of 82 single units and 36 multiple units from the 58-112 khz representations of the inferior colliculus, most (86%) displayed sensitivity to low-frequency sounds that was tuned in ...19958974996
fear conditioned discrimination of frequency modulated sweeps within species-specific calls of mustached and echolocation vocalizations of bats contain different patterns of frequency modulations. an adult bat's ability to discriminate between various fm parameters, however, is not well established. using changes in heart rate (hr) as a quantitative measure of associative learning, we demonstrate that mustached bats (pteronotus parnellii) can be fear conditioned to linear frequency modulated (fm) sweeps typically centered at their acoustic fovea (approximately 60 khz). we also show that hr i ...201020485675
basilar membrane resonance in the cochlea of the mustached bat.the mustached bat (pteronotus parnellii) detects the wing beats of prey insects by resolving small frequency modulations in the return echoes to the constant frequency component of its echolocation call at about 61 khz. the fine frequency discrimination required for this task is due largely to the mechanical properties of the cochlea, as indicated indirectly by the presence of large otoacoustic emissions at 61 khz. a laser diode interferometer was used to measure basilar membrane displacements i ...19957816832
dscf neurons within the primary auditory cortex of the mustached bat process frequency modulations present within social calls.neurons in the doppler-shifted constant frequency processing (dscf) area in the primary auditory cortex of mustached bats, pteronotus parnellii, are multifunctional, responding both to echolocation and communication sounds. simultaneous presentation of a dscf neuron's best low and high frequencies (bf(low) and bf(high), respectively) facilitates its response. bf(low) corresponds to a frequency in the frequency-modulated (fm) component of the first harmonic in the echolocation pulse, and bf(high) ...200818768643
morphology of the abdominal wall in the bat, pteronotus parnellii (microchiroptera: mormoopidae): implications for biosonar vocalization.we investigated the structure of the abdominal wall of pteronotus parnellii and made comparisons with eight other species of microchiroptera and one megachiropteran. similar to other mammals, the abdominal wall of bats consists of the three flank muscles laterally and the m. rectus abdominis ventrally. in microchiroptera, flank muscles are mostly confined to dorsal portions of the wall. the mm. transversus abdominis and obliquus internus abdominis form the bulk of the wall; the m. obliquus exter ...19957869386
isoflurane increases amplitude and incidence of evoked and spontaneous otoacoustic emissions.the volatile anesthetic isoflurane was tested for its effect on cochlear function by means of measuring distortion product otoacoustic emissions (dpoae) and spontaneous otoacoustic emissions (soae) in the mustached bat (pteronotus parnellii parnellii). averaged growth functions of dpoae and spontaneous otoacoustic emissions were assessed and compared between the control group (no isoflurane application) and the isoflurane group (application of isoflurane at vaporizer settings sof about 1.5-2%). ...200415276684
combination sensitivity and processing of communication calls in the inferior colliculus of the moustached bat pteronotus parnellii.many animals use complex communication calls in social behaviors. in some species we know the features in the calls that elicit particular behaviors, but we do not understand how the auditory system encodes the calls. nor do we understand the mechanisms underlying neural selectivity to calls. our studies of the auditory midbrain of the moustached bat pteronotus parnellii have revealed a neural mechanism important for generating selective responses to calls. neurons that integrate information acr ...200415258635
evidence of bartonella spp. in blood and ticks (ornithodoros hasei) of bats, in french guiana.we screened blood from 59 bats from french guiana for bartonella spp. pcrs were positive for 13.6% and culture was positive in one noctilio albiventris and one pteronotus parnellii, as well as in ornithodoros hasei ticks collected from bats. two isolated strains represent possible two new species.201627305604
acuity in ranging based on delay-tuned combination-sensitive neurons in the auditory cortex of mustached bats.a 1.0-ms echo delay from an emitted bio-sonar pulse at 25 °c corresponds to a 17.3-cm target distance. in the auditory cortex of the mustached bat, pteronotus parnellii, neurons tuned to a specific delay (best delay) of an echo from an emitted pulse are clustered in the ff, dorsal fringe and ventral fringe areas. ("ff" stands for the frequency-modulated components of a pulse and its echo.) those delay-tuned neurons are systematically arranged in the ff area according to their best delays and for ...201728505528
oxytocin and vasopressin immunoreactivity within the forebrain and limbic-related areas in the mustached bat, pteronotus parnellii.the nonapeptides, oxytocin and arginine vasopressin, play an important role in mammalian social and reproductive behavior. using immunocytochemical procedures, we identified oxytocin-immunoreactive neurons in the frontal and auditory cortices, limbic areas such as the medial septal nucleus, horizontal limb of the diagonal band and the amygdala. only arginine vasopressin neurons were present in the bed nucleus of the stria terminalis. in limbic-related areas, the hypothalamic paraventricular and ...200414726624
doppler-shift compensation by the mustached bat: quantitative data.quantitative data for doppler-shift compensation by pteronotus parnellii parnellii were obtained with a device which propelled the bats at constant velocities over a distance of 12 m. the bats compensated for doppler shifts at all velocities tested (0.1-5.0 ms-1). the main findings were (1) that compensation was usually accomplished by a progressive lowering of the approximately 61 khz second harmonic constant-frequency component of emitted sounds in small frequency steps (93 +/- 72 hz); (2) tha ...19947964378
differences in velocity-information processing between two areas in the auditory cortex of mustached bats.the bio-sonar pulse of the mustached bat, pteronotus parnellii parnellii, consists of four harmonics of constant frequency (cf1-4) and frequency-modulated (fm1-4) components. the cf and fm components carry velocity and distance information, respectively. in the auditory cortex of mustached bats, the cc ("c" stands for constant frequency) and dif (dorsal intrafossa) areas consist of cf/cf neurons tuned to a combination of pulse cf1 and echo cfn (n = 2 or 3). they show facilitative responses to pu ...201728456093
dietary overlap and seasonality in three species of mormoopid bats from a tropical dry forest.competing hypotheses explaining species' use of resources have been advanced. resource limitations in habitat and/or food are factors that affect assemblages of species. these limitations could drive the evolution of morphological and/or behavioural specialization, permitting the coexistence of closely related species through resource partitioning and niche differentiation. alternatively, when resources are unlimited, fluctuations in resources availability will cause concomitant shifts in resour ...201526369564
development of echolocation calls in the mustached bat, pteronotus mustached bats employ doppler-sensitive sonar to hunt fluttering prey insects in acoustically cluttered habitats. the echolocation call consists of 4-5 harmonics, each composed of a long constant frequency (cf) component flanked by brief frequency modulations (fm). the 2nd harmonic cf component (cf2) at 61 khz is the most intense, and analyzed by an exceptionally sharply tuned auditory system. the maturation of echolocation calls and the development of doppler-shift compensation was studie ...200314534267
mitochondrial genome of the neotropical parnell's mustached bat pteronotus parnellii (pteronotus, mormoopidae).we reported complete mitochondrial genome of neotropical parnell's mustached bat pteronotus parnellii (16,564 bp in length). its mitochondrial genome consisted of 13 protein-coding genes, 22 transfer rna genes, 2 ribosomal rna genes and 1 control region. the base composition of mtdna was a (33.1%), g (13.7%), c (27.3%), t (25.9%), and the percentage of a and t (59.0%) was higher than g and c. all the genes in p. parnellii were distributed on the h-strand, except for the nd6 subunit gene and 10 t ...201524409886
evolution of the heteroharmonic strategy for target-range computation in the echolocation of mormoopidae.echolocating bats use the time elapsed from biosonar pulse emission to the arrival of echo (defined as echo-delay) to assess target-distance. target-distance is represented in the brain by delay-tuned neurons that are classified as either "heteroharmonic" or "homoharmormic." heteroharmonic neurons respond more strongly to pulse-echo pairs in which the timing of the pulse is given by the fundamental biosonar harmonic while the timing of echoes is provided by one (or several) of the higher order h ...201323781209
labile cochlear tuning in the mustached bat. ii. concomitant shifts in neural tuning.acoustic stimuli near 60 khz elicit pronounced resonance in the cochlea of the mustached bat (pteronotus parnellii parnellii). the cochlear resonance frequency (crf) is near the second harmonic, constant frequency (cf2) component of the bat's biosonar signals. within narrow bands where cf2 and third harmonic (cf3) echoes are maintained, the cochlea has sharp tuning characteristics that are conserved throughout the central auditory system. the purpose of this study was to examine the effects of t ...19938441122
neurons in the inferior colliculus of the mustached bat are tuned both to echo-delay and sound duration.echolocation in bats requires a precise temporal processing of complex signals. this processing of time includes the encoding of echo-delay, which gives an estimation of target distance, and sound duration, which is considered to be important for own sound or echo recognition. in this study, we report that delay-tuned neurons in the inferior colliculus of the mustached bat (pteronotus parnellii) are also tuned to sound duration. collicular delay-tuned neurons showed three types of duration tunin ...201323492868
ultrasonic vocalizations of flying bats monitored by radiotelemetry.ultrasonic vocalizations of flying bats were effectively monitored with radiotelemetry. we describe a device light enough to be carried by an 11 g bat for periods of up to 1 h. it transmitted signals adequate for fine frequency analysis within a range of approximately 3 m. telemetry permitted the recording of constant-frequency pulses free from flight-induced doppler shifts and without time delays. the difference in frequency between telemetered signals and the same signals detected by a remote ...19921487718
a new spirurid (nematoda) parasite from mormoopid bats in mexico.a new nematode species, spirura mexicana n. sp., is described from specimens recovered from the esophageal mucosa of the parnell's mustached bat pteronotus parnellii , davy's naked-backed bat pteronotus davyi, wagner's mustached bat pteronotus personatus, and the ghost-faced bat mormoops megalophylla in the state of morelos, mexico. this nematode is characterized by having a relatively short prostoma, 5-6 pairs of caudal papillae, and a smooth distal end of the tail in females. this is the first ...201222509820
high-frequency two-tone distortions from the ear of the mustached bat, pteronotus parnellii reflect enhanced cochlear tuning. 19921436119
diversification and reproductive isolation: cryptic species in the only new world high-duty cycle bat, pteronotus parnellii.molecular techniques are increasingly employed to recognize the presence of cryptic species, even among commonly observed taxa. previous studies have demonstrated that bats using high-duty cycle echolocation may be more likely to speciate quickly. pteronotus parnellii is a widespread neotropical bat and the only new world species to use high-duty cycle echolocation, a trait otherwise restricted to old world taxa. here we analyze morphological and acoustic variation and genetic divergence at the ...201323360354
spectral integration in the inferior colliculus: role of glycinergic inhibition in response facilitation.this study examined the contribution of glycinergic inhibition to the time-sensitive spectral integration performed by neurons in the inferior colliculus of the mustached bat (pteronotus parnellii). these neurons are sometimes called combination-sensitive because they display facilitatory (or inhibitory) responses to the combination of distinct spectral elements in sonar or social vocalizations. present in a wide range of vertebrates, their temporally and spectrally selective integration is thou ...200111157095
specializations for sharp tuning in the mustached bat: the tectorial membrane and spiral limbus.the sense of hearing in the mustached bat, pteronotus parnellii, is specialized for fine frequency analysis in three narrow bands that correspond to approx 30, 60 and 90 khz constant frequency harmonics in the biosonar signals used for doppler-shift compensation and acoustic imaging of the environment. previous studies have identified anatomical specializations in and around the area of the cochlea that processes the dominant second harmonic component, but similar features have not been found in ...19911769907
modulation of responses and frequency tuning of thalamic and collicular neurons by cortical activation in mustached the jamaican mustached bat, pteronotus parnellii parnellii, one of the subdivisions of the primary auditory cortex is disproportionately large and over-represents sound at approximately 61 khz. this area, called the doppler-shifted constant frequency (dscf) processing area, consists of neurons extremely sharply tuned to a sound at approximately 61 khz. we found that a focal activation of the dscf area evokes highly specific corticofugal modulation in the inferior colliculus and medial genicul ...200010899207
facilitation and delay sensitivity of auditory cortex neurons in cf - fm bats, rhinolophus rouxi and pteronotus p.parnellii.responses of auditory neurons to complex stimuli were recorded in the dorsal belt region of the auditory cortex of two taxonomically unrelated bat species, rhinolophus rouxi and pteronotus parnellii parnellii, both showing doppler shift compensation behaviour. as in p.p.parnellii (suga et al., j. neurophysiol., 49, 1573 - 1626, 1983), cortical neurons of r.rouxi show facilitated responses to pairs of pure tones or frequency modulations. best frequencies for the two components lie near the first ...199112106246
frequency organization and responses to complex sounds in the medial geniculate body of the mustached bat.the auditory cortex of the mustached bat (pteronotus parnellii) displays some of the most highly developed physiological and organizational features described in mammalian auditory cortex. this study examines response properties and organization in the medial geniculate body (mgb) that may contribute to these features of auditory cortex. about 25% of 427 auditory responses had simple frequency tuning with single excitatory tuning curves. the remainder displayed more complex frequency tuning usin ...199910561424
facilitatory and inhibitory frequency tuning of combination-sensitive neurons in the primary auditory cortex of mustached bats.mustached bats, pteronotus parnellii parnellii, emit echolocation pulses that consist of four harmonics with a fundamental consisting of a constant frequency (cf(1-4)) component followed by a short, frequency-modulated (fm(1-4)) component. during flight, the pulse fundamental frequency is systematically lowered by an amount proportional to the velocity of the bat relative to the background so that the doppler-shifted echo cf(2) is maintained within a narrowband centered at approximately 61 khz. ...199910561409
ultrastructure of the parotid gland in two species of naked-backed bats.naked-backed bats of the genus pteronotus (family mormoopidae) occur in the neotropics from mexico through northern south america. these are relatively small-sized insectivorous species that frequently roost in caves. eight specimens of naked-backed bats (pteronotus parnellii) were live-trapped in suriname and one in cuba (p. quadridens). their parotid glands were fixed in an aldehyde mixture designed for field work and postfixed in the laboratory with osmium tetroxide. tissues were further prep ...199910359512
the emission pattern of vocalizations and directionality of the sonar system in the echolocating bat, pteronotus parnelli.the radiation patterns of the first three harmonics (approx. 30, 60, 90 khz) of the mustached bat biosonar signal were measured from vocalizations elicited by cortical microstimulation. the primary foci of the acoustic beam patterns were in front of the mouth but somewhat below the horizontal plane. the prominent second and third harmonics showed sharp cutoffs between 20 degrees and 30 degrees lateral to the midline. sidelobes were found, suggesting the influence of some vocal tract interference ...19911861003
corticofugal amplification of facilitative auditory responses of subcortical combination-sensitive neurons in the mustached bat.recent studies on the bat's auditory system indicate that the corticofugal system mediates a highly focused positive feedback to physiologically "matched" subcortical neurons, and widespread lateral inhibition to physiologically "unmatched" subcortical neurons, to adjust and improve information processing. these findings have solved the controversy in physiological data, accumulated since 1962, of corticofugal effects on subcortical auditory neurons: inhibitory, excitatory, or both (an inhibitor ...199910036282
auditory motion induces directionally dependent receptive field shifts in inferior colliculus neurons.this research focused on the response of neurons in the inferior colliculus of the unanesthetized mustached bat, pteronotus parnelli, to apparent auditory motion. we produced the apparent motion stimulus by broadcasting pure-tone bursts sequentially from an array of loudspeakers along horizontal, vertical, or oblique trajectories in the frontal hemifield. motion direction had an effect on the response of 65% of the units sampled. in these cells, motion in opposite directions produced shifts in r ...19989535967
afferent connections to the dorsal nucleus of the lateral lemniscus of the mustache bat: evidence for two functional subdivisions.the dorsal nucleus of the lateral lemniscus (dnll) of the mustache bat, pteronotus parnellii, was found to consist of two divisions. the neurons in each division were distinguished by their temporal discharge patterns evoked both by tone bursts and sinusoidal amplitude-modulated (sam) signals. neurons in the anterior one-third of the dnll responded to tone bursts with an onset discharge pattern and only phase-locked to sam signals with low modulation frequencies (< 300 hz). neurons in the poster ...19968889945
principles of auditory information-processing derived from neuroethology.for auditory imaging, a bat emits orientation sounds (pulses) and listens to echoes. the parameters characterizing a pulse-echo pair each convey particular types of biosonar information. for example, a doppler shift (a difference in frequency between an emitted pulse and its echo) carries velocity information. for a 61-khz sound, a 1.0-khz doppler shift corresponds to 2.8 ms-1 velocity. the delay of the echo from the pulse conveys distance (range) information. a 1.0-ms echo delay corresponds to ...19892689566
the shape of 2f1-f2 suppression tuning curves reflects basilar membrane specializations in the mustached bat, pteronotus parnellii.iso-suppression tuning curves (stcs) of the 2f1-f2 distortion product (dp) were measured over a primary frequency range of 20 to 93 khz in mustached bats, pteronotus parnellii parnellii. primary levels were chosen to produce dp levels between 0 and 7 db spl. at frequencies outside the ranges of 60-72 khz and 90-93 khz the shapes of the stcs were symmetrical or asymmetrical with a steep high frequency slope. in the vicinity of 61 khz where a strong stimulus frequency otoacoustic emission (sfoae) ...19957607981
respiratory muscle activity in relation to vocalization in flying bats.the structure of the thoracic and abdominal walls of pteronotus parnellii (microchiroptera: mormoopidae) was described with respect to their function in respiration and vocalization. we monitored electromyographic activity of respiratory and flight muscles in relation to echolocative vocalization. in flight, signals were telemetered with a small fm transmitter modified to summate the low-frequency myopotentials with biosonar signals from a ceramic-crystal microphone. recordings were also made fr ...19957891034
analysis of acoustic elements and syntax in communication sounds emitted by mustached bats.mustached bats, pteronotus parnellii parnellii spend most of their lives in the dark and use their auditory system for acoustic communication as well as echolocation. the sound spectrograms of their communication sounds or "calls" revealed that this species produces a rich variety of calls. these calls consist of one or more of the 33 different types of discrete sounds or "syllables" that are emitted singly and/or in combination. these syllables can be further classified as 19 simple syllables, ...19947962992
the neurons of the medial geniculate body in the mustached bat (pteronotus parnellii).the neurons in the medial geniculate body were studied in golgi preparations from adult mustached bats (pteronotus parnellii). their somatic and dendritic configurations were compared with those of cells in other, nonecholocating mammals. a second goal was to use the thalamic nuclear subdivisions derived from golgi material to integrate the findings in parallel studies of cytoarchitecture, immunocytochemistry, and tectothalamic connections. three primary divisions are defined. the ventral divisi ...19947962716
cytoarchitecture of the medial geniculate body in the mustached bat (pteronotus parnellii).the cytoarchitectonic organization of the medial geniculate body and adjoining thalamic nuclei was analyzed in the mustached bat (pteronotus parnellii). these subdivisions provide a reference for structural, physiological, connectional, and neurochemical work. most nuclei recognized in other mammals exist in the mustached bat, although the relative volume of the three divisions was species specific. the ventral division contains medium-sized neurons and a few smaller cells and is well developed. ...19947962715
convergence of ascending pathways at the inferior colliculus of the mustache bat, pteronotus compare patterns of projections to the inferior colliculus from different sources, injections of [3h]-leucine were placed in the cochlear nuclei, superior olivary complex, and nuclei of the lateral lemniscus of pteronotus parnellii. the results show that the target of the anteroventral cochlear nucleus (avcn) is the ventral and lateral two thirds of the central nucleus of the inferior colliculus. the binaural pathways from the medial and lateral superior olives (mso and lso) project to the sa ...19873611416
ache-staining of type ii ganglion cells, processes and terminals in the cochlea of the mustached bat.there have been a number of reports showing that ganglion cells of sensory neurons may be stained by traditional acetylcholinesterase (ache) histochemical techniques commonly used to demonstrate efferent nerve fibers and terminals. ache-staining has been described for cell bodies in the vestibular and spiral ganglia; staining of peripheral and central processes, however, is rare and the presence of reaction product in afferent terminals has not been reported. the outer hair cells of mustached ba ...19947520902
response properties of fm-fm combination-sensitive neurons in the auditory cortex of the mustached bat.for echolocation, the mustached bat, pteronotus parnellii rubiginosus, emits orientation sounds (pulses) and listens to echoes. each pulse is made up of 8 components, of which 4 are constant frequencies (cf 1.4) and 4 are frequency-modulated (fm 1-4). target-range information, conveyed by the time delay of the echo fm from the pulse fm, is processed in this species by specialized neurons in a part of the auditory cortex known as the fm-fm area. these cortical neurons are responsive to pulse-echo ...19863772828
brain activity patterns in flying, echolocating bats (pteronotus parnellii): assessment by high resolution autoradiographic imaging with [3h]2-deoxyglucose.brain activity patterns during echolocation and flight were assessed in mustached bats (pteronotus parnellii parnellii). bats were injected intraperitoneally with [3h]2-deoxyglucose and restrained in a foam holder or allowed to fly for 20 min. under resting conditions, low levels of [3h]2-deoxyglucose uptake were observed throughout the forebrain but relatively high uptake was found in brainstem auditory and vestibular centers. in flying, echolocating bats, marked increases in regional [3h]2-deo ...19948058119
evidence for a mechanical filter in the cochlea of the 'constant frequency' bats, rhinolophus rouxi and pteronotus investigate the function of basilar membrane (bm) thickenings in the cochlea of bats which use constant frequency (cf) echolocation calls, acoustic distortion products were measured while placing the primary stimuli f1 and f2 at frequencies which are represented in the thickened bm regions. in rhinolophus, for primary stimuli between about 80-100 khz, pronounced maxima of the level of distortion products (2f1-f2, 3f1-2f2, 4f1-3f2) can be measured if the frequency separation between the two pr ...19948150747
otoacoustic emissions from the cochlea of the 'constant frequency' bats, pteronotus parnellii and rhinolophus rouxi.during stimulation with continuous pure tones, the cochlea of each individual of the mustached bat, pteronotus parnellii, produces a strong evoked stimulus-frequency otoacoustic emission (sfoae) at about 62 khz. the sfoaes were on average 480 hz above the dominant constant frequency component of the echolocation call (resting frequency, rf). in two out of nine individuals of pteronotus the sfoaes changed into spontaneous otoacoustic emissions of 25-40 db spl. in the rufuous horseshoe bat, rhinol ...19948150746
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