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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1904): 20230444, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38705172

ABSTRACT

Passive acoustic monitoring (PAM) is a powerful tool for studying ecosystems. However, its effective application in tropical environments, particularly for insects, poses distinct challenges. Neotropical katydids produce complex species-specific calls, spanning mere milliseconds to seconds and spread across broad audible and ultrasonic frequencies. However, subtle differences in inter-pulse intervals or central frequencies are often the only discriminatory traits. These extremities, coupled with low source levels and susceptibility to masking by ambient noise, challenge species identification in PAM recordings. This study aimed to develop a deep learning-based solution to automate the recognition of 31 katydid species of interest in a biodiverse Panamanian forest with over 80 katydid species. Besides the innate challenges, our efforts were also encumbered by a limited and imbalanced initial training dataset comprising domain-mismatched recordings. To overcome these, we applied rigorous data engineering, improving input variance through controlled playback re-recordings and by employing physics-based data augmentation techniques, and tuning signal-processing, model and training parameters to produce a custom well-fit solution. Methods developed here are incorporated into Koogu, an open-source Python-based toolbox for developing deep learning-based bioacoustic analysis solutions. The parametric implementations offer a valuable resource, enhancing the capabilities of PAM for studying insects in tropical ecosystems. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.


Subject(s)
Acoustics , Vocalization, Animal , Animals , Panama , Deep Learning , Species Specificity
2.
PeerJ ; 11: e16322, 2023.
Article in English | MEDLINE | ID: mdl-37941929

ABSTRACT

Background: Animal communication consists of signal production and perception, which are crucial for social interactions. The main form used by anurans is auditory communication, in most cases produced as advertisement calls. Furthermore, sound perception happens mainly through an external tympanic membrane, and plays an important role in social behavior. In this study, we evaluated the influence of body and tympanic membrane sizes on call frequency across the phylogeny of anurans. Methods: We use data on snout-vent length, tympanic membrane diameter, and dominant frequency of the advertisement call from the literature and from natural history museum collections. We mapped these traits across the anuran phylogeny and tested different models of diversification. Our final dataset includes data on body size, tympanic membrane size, and call dominant frequency of 735 anuran species. Results: The best explanatory model includes body and tympanum size with no interaction term. Although our results show that call frequency is strongly constrained by body and tympanum size, we identify five evolutionary shifts in allometry from that ancestral constraint. We relate these evolutionary shifts to the background noise experienced by populations. Body size is important for myriad ecological interactions and tympanum size is strongly associated with female call frequency preferences. Thus, allometric escape in frog calls might arise through environmental selection such as breeding in fast flowing or soundscape competition, as well as sexual selection linked to tympanum size.


Subject(s)
Biological Evolution , Hearing , Animals , Female , Phylogeny , Anura , Perception
3.
Conserv Physiol ; 11(1): coad079, 2023.
Article in English | MEDLINE | ID: mdl-37869263

ABSTRACT

Noise represents a threat to human and wildlife health, triggering physiological and behavioral challenges to individuals living close to sources of extreme noise. Here, we considered airport environments as sources of potentially stressful stimuli for birds and tested if those living near airports are under higher physiological stress than birds living in quiet sites. We used measurements of CORT in feathers (CORTf) as a proxy of chronic stress. We evaluated 14 passerine and 1 non-passerine species, living near three Brazilian airports. We found that, across species, individuals with a better body condition had lower CORTf concentration. At the species level, we found that CORTf concentration was not consistently affected by airport noise. Comparing individuals living in quiet sites with those living near airports, we found that 2 species had higher and 2 had lower CORTf concentrations near airports, while 11 species presented no significant differences between sites. At the population level, model selection indicated that the direction and strength of these differences are weakly related to species' song frequency (peak frequency), as lower-frequency singers tended to present higher CORTf levels at airport-affected sites. In summary, we were unable to find a consistent response among species, probably due to species-specific differences in their response to anthropogenic disturbances. Instead, we found that species might be affected differently according to their singing spectral frequency and that individuals in good body condition show lower CORTf, suggesting that this measure is consistent with lower physiological stress.

4.
PeerJ ; 11: e15687, 2023.
Article in English | MEDLINE | ID: mdl-37483973

ABSTRACT

Long-beaked common dolphin (Delphinus delphis bairdii) distribution is limited to the Eastern North Pacific Ocean. Its whistle repertoire is poorly investigated, with no studies in the Gulf of California. The aim of the present study is to characterize the whistles of this species and compare their parameters with different populations. Acoustic monitoring was conducted in La Paz Bay, Gulf of California. Recordings were inspected in spectrogram view in Raven Pro, selecting good quality whistles (n = 270). In the software Luscinia, contours were manually traced to obtain whistle frequencies and duration. Number of steps, inflection points and contour type were visually determined. We calculated the descriptive statistics of the selected whistle parameters and we compared the results with a dolphins population from the Eastern Pacific Ocean. Permutational multivariate analysis of variance (PERMANOVA) was performed to test the intraspecific variation of the whistle parameters among groups. In the present study the mean values (±SD) of the whistle parameters were: maximum frequency = 14.13 ± 3.71 kHz, minimum frequency = 8.44 ± 2.58 kHz and duration = 0.44 ± 0.31 s. Whistles with the upsweep contour were the most common ones (34.44%). The coefficient of variation (CV) values for modulation parameters were high (>100%), in accordance with other studies on dolphins. Whistle parameters showed significant differences among groups. Finally, ending and maximum frequencies, duration and inflection points of the whistles recorded in the present study were lower compared with the parameters of the long-beaked common dolphins from the Eastern Pacific Ocean. This study provides the first whistle characterization of long-beaked common dolphin from the Gulf of California and it will help future passive acoustic monitoring applications in the study area.


Subject(s)
Common Dolphins , Dolphins , Animals , Bays , Vocalization, Animal , Sound Spectrography/methods
5.
Proc Biol Sci ; 290(2000): 20230215, 2023 06 14.
Article in English | MEDLINE | ID: mdl-37312552

ABSTRACT

The study of ecological mechanisms influencing organisms' phenotypic variation is a central subject of evolutionary biology. In this study, we characterized morphological, plumage colour and acoustic variation in cactus wrens Campylorhynchus brunneicapillus throughout its distribution. We assessed whether Gloger's, Allen's and Bergmann's ecogeographical rules, and the acoustic adaptation hypothesis relate to geographical trait variation. We analysed specimen coloration in belly and crown plumage, beak shape and structural song characteristics. We tested whether the subspecific classification or the peninsular/mainland groups mirrored the geographical variation in phenotypes and whether ecological factors were associated with patterns of trait variation. Our results suggest that colour, beak shape and acoustic traits varied across the range, in agreement with two lineages described by genetics. The simple versions of Gloger's and Allen's rules are related to variations in colour traits and morphology. Conversely, patterns of phenotypic variation did not support Bergmann's rule. The acoustic adaptation hypothesis supported song divergence for frequency-related traits. Phenotypic variation supports the hypothesis of two taxa: C. affinis in the Baja California peninsula and C. brunneicapillus in the mainland. The ecological factors are associated with phenotypic trait adaptations, suggesting that divergence between lineages could result from ecological divergence.


Subject(s)
Cactaceae , Songbirds , Animals , Songbirds/genetics , Color , Mexico , Phenotype
6.
PeerJ ; 11: e15292, 2023.
Article in English | MEDLINE | ID: mdl-37334123

ABSTRACT

Coastal dolphins and porpoises such as the Chilean dolphin (Cephalorhynchus eutropia), the Peale's dolphin (Lagenorhynchus australis), and the Burmeister's porpoise (Phocoena spinipinnis) inhabit the remote areas of Chilean Patagonia. Human development is growing fast in these parts and may constitute a serious threat to such poorly known species. It is thus urgent to develop new tools to try and study these cryptic species and find out more about their behavior, population levels, and habits. These odontocetes emit narrow-band high-frequency (NBHF) clicks and efforts have been made to characterize precisely their acoustic production. Passive acoustic monitoring is a common way to study these animals. Nevertheless, as the signal frequency is usually higher than 100 kHz, storage problems are acute and do not allow for long-term monitoring. The solutions for recording NBHF clicks are usually twofold: either short duration, opportunistic recording from a small boat in presence of the animals (short-term monitoring) or long-term monitoring using devices including a click detector and registering events rather than sound. We suggest, as another possibility, medium-term monitoring, arguing that today's devices have reached a level of performance allowing for a few days of continual recording even at these extremely high frequencies and in difficult conditions, combined with a long-term click detector. As an example, during 2021, we performed a quasi-continuous recording for one week with the Qualilife High-Blue recorder anchored in a fjord near Puerto Cisnes, Region de Aysen, Chile. We detected more than 13,000 clicks, grouped in 22 periods of passing animals. Our detected clicks are quite similar to precedent results but, due to the large number of clicks recorded, we find a larger variability of parameters. Several rapid sequences of clicks (buzz) were found in the recordings and their features are consistent with previous studies: on average they have a larger bandwidth and a lower peak frequency than the usual clicks. We also installed in the same place a click detector (C-POD) and the two devices compare well and show the same number and duration of periods of animals presence. Passages of odontocetes were happening on average each three hours. We thus confirm the high site fidelity for the species of dolphins emitting NBHF clicks present in this zone. Finally, we confirm that the combined use of recording and detection devices is probably a good alternative to study these poorly known species in remote areas.


Subject(s)
Dolphins , Phocoena , Animals , Humans , Chile , Cetacea , Acoustics
7.
PeerJ ; 11: e15393, 2023.
Article in English | MEDLINE | ID: mdl-37250715

ABSTRACT

Background: The delimitation of cryptic species is a challenge for biodiversity conservation. Anurans show high cryptic diversity levels, and molecular species delimitation methods could help identify putative new species. Additionally, species delimitation approaches can provide important results for cryptic species conservation, with integrative methods adding robustness to results. Ischnocnema manezinho was described from Santa Catarina Island (SCI), southern Brazil. More recently, some inventories indicated continental populations supposedly similar in morphology to it. If these records are confirmed as I. manezinho, it would likely change its endangered status on National Red List, removing the species from conservation agendas. We investigated the threatened frog Ischnocnema manezinho, to evaluate if the continental populations belong to this species or if they form an undescribed species complex. Methods: We used coalescent, distance, and allele-sharing-based species delimitation methods and integrative analyses of morphometric and bioacoustics traits to test evolutionary independence between I. manezinho from SCI, Arvoredo Island, and continental populations. Results: Ischnocnema manezinho is restricted to Santa Catarina Island, while the five remaining lineages should be further investigated through a taxonomic review. Our results point to a small geographic range of Ischnocnema manezinho. Additionally, the species occurs in isolated fragments of forest in SCI surrounded by expanding urban areas, confirming its status as Endangered. Thus, the protection and monitoring of I. manezinho and the taxonomic description of the continental and Arvoredo Island candidate species should be priorities.


Subject(s)
Anura , Forests , Animals , Phylogeny , Anura/genetics , Biodiversity , Plant Leaves
8.
Trop Anim Health Prod ; 55(3): 166, 2023 Apr 21.
Article in English | MEDLINE | ID: mdl-37083857

ABSTRACT

The use of sensors for livestock monitoring has grown in the last decade, motivated not only by the search for improvements in animal production and health, but also by the better use of physical, financial, and human resources in the management of livestock. Since precision livestock farming depends on technological innovation, including the use of sensors, it is essential to validate their applicability in confined animals. Therefore, the objective was to evaluate the functioning of the SCR Heatime® HR System sensor in heifers and analyze the behavioral differences of these animals in two feedlot systems (tie-stall and loose-housing). Eleven Gyr heifers of 10 months of age and an average body weight of 179 ± 26 kg were used. Animals were equipped with the SCR Heatime® HR System 7 days before the evaluations for adaptation, with the behavioral and system studies carried out during two periods each of 5 days, for 8 h a day. Five heifers were housed in tie-stall bedding and six were housed in loose-housing. After the evaluations for a period, animals have been switched systems in the following period. While the animals had the sensors attached to their bodies, behavioral evaluations were also performed visually, every 3 min by two evaluators per system. Behavior activities were characterized as standing, lying, idle standing, idle lying, ruminating standing, ruminating lying, feed, and water intake. The regression for the rumination activity recorded between the sensor and the visual assessment was significant only for loose-housing (P = 0.0002), but the Pearson correlation between both was negative and low (r = - 0.25; P = 0.0002). The sensor overestimated rumination by 27.3% in loose-housing (28 vs. 22 min/2 h) and 38.5% in tie-stall (36 vs. 26 min/2 h). Thus, when considering the different feedlot systems, validation was not possible due to the overestimation of time spent on rumination activity determined by the sensor. In the behavioral comparison between the systems by visual assessment, there was a significant difference (P < 0.05) for the behaviors of motor activity, idle lying, total idle time, and feed intake between the animals in the two housing systems. As for idle standing, ruminating standing, total rumination time, and water intake, there was no difference (P > 0.05). However, the time spent ruminating lying was greater from 10:00 to 12:00 h (43 ± 3 min/2 h) in the tie-stall, whereas in the loose-housing the animals distribute more uniformly their rumination from 08:00 to 16:00 h (26 min/2 h on average). Therefore, the use of the SCR Heatime® HR System sensor is not recommended for Gyr heifers housed in tie-stall and loose-housing systems. Regarding the daytime range of rumination and the accuracy improvements of similar sensors, it is recommended to develop them in both feedlot systems using the periods of less rumination in early morning in tie-stall and late afternoon in loose-housing.


Subject(s)
Eating , Feeding Behavior , Humans , Cattle , Animals , Female , Behavior, Animal , Drinking , Agriculture , Housing, Animal
9.
Evolution ; 77(2): 355-369, 2023 02 04.
Article in English | MEDLINE | ID: mdl-36611281

ABSTRACT

The acoustic adaptation hypothesis (AAH) and ecological character displacement (ECD) are two potential mechanisms shaping call evolution that can predict opposite trends for the differentiation of signals. Under AAH, signals evolve to minimize environmental degradation and maximize detection against background noise, predicting call homogenization in similar habitats due to environmental constraints on signals. In contrast, ECD predicts greater differences in call traits of closely related taxa in sympatry because of selection against acoustic interference. We used comparative phylogenetic analyses to test the strength of these two selective mechanisms on the evolution of advertisement calls in glassfrogs, a highly diverse family of neotropical anurans. We found that, overall, acoustic adaptation to the environment may outweigh effects of species interactions. As expected under the AAH, temporal call parameters are correlated with vegetation density, but spectral call parameters had an unexpected inverse correlation with vegetation density, as well as an unexpected correlation with temperature. We detected call convergence among co-occurring species and also across multiple populations from the same species in different glassfrogs communities. Our results indicate that call convergence is common in glassfrogs, likely due to habitat filtering, while character displacement is relatively rare, suggesting that costs of signal similarity among related species may not drive divergent selection in all systems.


Subject(s)
Ecosystem , Vocalization, Animal , Animals , Phylogeny , Anura/genetics , Acoustics , Biological Evolution
10.
PeerJ ; 10: e13969, 2022.
Article in English | MEDLINE | ID: mdl-36071828

ABSTRACT

Passive acoustic monitoring (PAM) is a promising method for biodiversity assessment, which allows for longer and less intrusive sampling when compared to traditional methods (e.g., collecting specimens), by using sound recordings as the primary data source. Insects have great potential as models for the study and monitoring of acoustic assemblages due to their sensitivity to environmental changes. Nevertheless, ecoacoustic studies focused on insects are still scarce when compared to more charismatic groups. Insects' acoustic activity patterns respond to environmental factors, like temperature, moonlight, and precipitation, but community acoustic perspectives have been barely explored. Here, we provide an example of the usefulness of PAM to track temporal patterns of acoustic activity for a nocturnal assemblage of insects (Orthoptera). We integrate satellite remote sensing and astronomically measured environmental factors at a local scale in an Andean Forest of Colombia and evaluate the acoustic response of orthopterans through automated model detections of their songs for nine weeks (March and April of 2020). We describe the acoustic frequency range and diel period for the calling song of each representative species. Three species overlapped in frequency and diel acoustics but inhabit different strata: canopy, understory, and ground surface level. Based on the acoustic frequency and activity, we identified three trends: (i) both sampled cricket species call at lower frequency for shorter periods of time (dusk); (ii) all sampled katydid species call at higher frequency for longer time periods, including later hours at night; and (iii) the diel acoustic activity span window seems to increase proportionally with dominant acoustic frequency, but further research is required. We also identified a dusk chorus in which all the species sing at the same time. To quantify the acoustic response to environmental factors, we calculated a beta regression with the singing activity as a response variable and moon phase, surface temperature and daily precipitation as explanatory variables. The response to the moon phase was significant for the katydids but not for the crickets, possibly due to differences in diel activity periods. Crickets are active during dusk, thus the effects of moonlight on acoustic activity are negligible. The response to precipitation was significant for the two crickets and not for the katydids, possibly because of higher likelihood of rain interrupting crickets' shorter diel activity period. Our study shows how the local survey of orthopteran acoustic assemblages, with a species taxonomic resolution coupled with remote-sensing environmental measurements can reveal responses to environmental factors. In addition, we demonstrate how satellite data might prove to be a useful alternative source of environmental data for community studies with geographical, financial, or other constraints.


Subject(s)
Orthoptera , Remote Sensing Technology , Animals , Orthoptera/physiology , Acoustics , Temperature , Sound Spectrography
11.
Pap. avulsos zool ; 62: e202262036, 2022. mapas, graf, tab
Article in English | VETINDEX | ID: biblio-1396446

ABSTRACT

Scinax comprises 129 species of treefrogs divided between the S. ruber and the S. catharinae clades. The S. rostratus group belongs to the S. ruber clade, and comprises ten species characterized by having a dark interorbital triangular mark, tubercle on the heel and by vocalizing in a head-down position. Within this group, S. kennedyi and S. rostratus are similar in that they are the only species that do not possess a row of tubercles on the lower jaw. In spite of their morphological similarity, they can be distinguished from each other by male size and advertisement call traits. Scinax kennedyi was described from eastern Colombia, and occurs from central Colombia to western Venezuela, whereas S. rostratus was described from northern Venezuela, and is thought to occur from Panama to eastern Venezuela, and in the Brazilian state of Pará. A recent study reported a population identified as S. rostratus from the state of Roraima, in northern Brazil. However, this population presented substantial differences in male size and advertisement call in comparison to the described for this species, and apparently it best fits the diagnosis of S. kennedyi instead. In view of this, the present study aimed to clarify the identity of this Brazilian population through a reassessment of its specimens and call recordings, together with the examination of data of S. kennedyi from its type locality, and of S. rostratus from northern Venezuela. Acoustic and morphological analyses revealed that specimens from northern Brazil were indeed misidentified as S. rostratus, and hence they were herein reassigned to S. kennedyi. The study therefore demonstrates the occurrence of S. kennedyi in Brazil, extending its distribution ca. 1,120 km east by south from its type locality, and ca. 844 km east-southeast from its easternmost previous record. With this reassessment, a clearer acoustic diagnosis between S. kennedyi and S. rostratus was provided, as well as further data on fine-scale temporal traits of their calls.(AU)


Subject(s)
Animals , Anura/classification , Speech Acoustics , Animal Distribution , Species Specificity , Brazil
12.
Pap. avulsos zool ; 62: e202262018, 2022. tab, ilus
Article in English | VETINDEX, SESSP-ILSLPROD, Sec. Est. Saúde SP, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1363782

ABSTRACT

Although communication capabilities are displayed by many vertebrate groups, some repertoires are poorly known, such as the case of xenarthrans, particularly armadillos, for which vocalization as a source of communicating to others remains poorly understood and relies on punctual reports of sounds. Here we provide the first description of a behavioral response associated with sound emission of two subjects of Dasypus novemcinctus. Both audio and visual registration was performed to subsequent analyses of expressed behaviors and emitted calls, which accounted for 76 vocalizations from a total of eight video recordings randomly collected from 2017 to 2019. Sound is acoustically characterized by both inhale and exhale phases composed of two vocal units, and no harmonic structure was observed. Once the subjects have always produced these vocalizations while cornered and exhibiting defensive behavior against another subject/human disturbance, these vocalizations were termed as distress. Subjects produced a hiss-purr-like sound while trying to avoid contact with another by bowing or lowering their bodies, humping, or even moving elsewhere when sound production ceased. This shows that the sound repertoire of armadillos is still to be unveiled and seems to be much more complex than previously thought.(AU)


Subject(s)
Animals , Armadillos , Vocalization, Animal , Behavior, Animal , Agonistic Behavior , Ethology
13.
Folia Primatol (Basel) ; 92(3): 151-163, 2021.
Article in English | MEDLINE | ID: mdl-34350867

ABSTRACT

Vocal communication is an essential aspect of primate social behaviour. The bearded capuchin Sapajus libidinosus is endemic to Brazil, and some studies have described specific vocalisation types for this species; however, there is still no complete description of its vocal repertoire. Thus, this study aimed to describe the vocal repertoire of a group of S. libidinosus living in theParque Nacional de Brasília, a protected area in the Cerrado area of Central Brazil. We carried out focal samplings and recording of vocalisations of members of an S. libidinosus troop in different behavioural contexts. The call analyses revealed 25 different types of vocalisations, and each call presented significant structural variation. We grouped these vocalisations according to the context of the emission or acoustic structure into the following categories: contact calls (contact note, infant babbling, trill, teeth- and lip-smacking, and sirena); foraging calls (chihui, grgr, and patinado); whistle series (food-associated, long-distance, and intergroup encounter); aggressive calls (aggressive contact note, ascending rapid staccato, cough cough, and pip); calls in response to aggression (scream, squeal, and pulsed scream), sexual display calls (chuck and raspy oestrous call), and stress-related calls (alarm call/bark, hiccup, hip, double hip, and wah wah). S. libidinosus presented a very rich vocal repertoire, revealing a pattern consistent with the repertoire of other capuchin monkey species. This is the first comprehensive description of the S. libidinosus vocal repertoire and highlights the complexity of neotropical primate communication.


Subject(s)
Cebinae/psychology , Vocalization, Animal , Animals , Brazil , Female , Male
14.
Mar Pollut Bull ; 169: 112502, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34029799

ABSTRACT

The aim of this study is to characterize the background noise and abiotic and anthropogenic sound sources in the sector with greater anthropogenic use of the Cananéia estuary. The results show that the relative amplitude of background noise decreased with the increase of frequency range, and was higher with greater number of vessels, wind speed and during flood tide. Weekends and vacation periods were shown to be important dates during which background noise increased in the region. The influence of the tide and the wind speed on the relative amplitude was dependent on the frequency range analyzed. Therefore, both abiotic and anthropogenic sound sources were observed to be important factors regarding an increase in background noise in Cananéia. The importance of the continuity of vessel regulation in the region and of future studies that identify whether such noises alter parameters from the sound repertoire of the cetacean species in the region.


Subject(s)
Acoustics , Estuaries , Brazil , Noise/adverse effects , Sound
15.
Ecology ; 102(7): e03380, 2021 07.
Article in English | MEDLINE | ID: mdl-33937979

ABSTRACT

Acoustic signaling is key in mediating mate choice, which directly impacts individual fitness. Because background noise and habitat structure can impair signal transmission, the acoustic space of mixed-species assemblages has long been hypothesized to reflect selective pressures against signal interference and degradation. However, other potential drivers that received far less attention can drive similar outputs on the acoustic space. Phylogenetic niche conservatism and allometric constraints may also modulate species acoustic features, and the acoustic space of communities could be a side-effect of ecological assembly processes involving other traits (e.g., environmental filtering). Additionally, the acoustic space can also reflect the sorting of species relying on public information through extended communication networks. Using an integrative approach, we revisit the potential drivers of the acoustic space by addressing the distribution of acoustic traits, body size, and phylogenetic relatedness in tropical anuran assemblages across gradients of environmental heterogeneity in the Pantanal wetlands. We found the overall acoustic space to be aggregated compared with null expectations, even when accounting for confounding effects of body size. Across assemblages, acoustic and phylogenetic differences were positively related, while acoustic and body size similarities were negatively related, although to a minor extent. We suggest that acoustic partitioning, acoustic adaptation, and allometric constraints play a minor role in shaping the acoustic output of tropical anuran assemblages and that phylogenetic niche conservatism and public information use would influence between-assemblage variation. Our findings highlight an overlooked multivariate nature of the acoustic dimension and underscore the importance of including the ecological context of communities to understand drivers of the acoustic space.


Subject(s)
Ecosystem , Wetlands , Acoustics , Animals , Anura , Phylogeny
16.
PeerJ ; 9: e11105, 2021.
Article in English | MEDLINE | ID: mdl-33981488

ABSTRACT

Echolocation clicks can reflect the anatomy of the vocalizing animal, enabling the distinction of species. River dolphins from the family Iniidae are formally represented by one species and two subspecies (Inia geoffrensis geoffrensis and I. g. humboldtiana). Additionally, two other species have been proposed (I. boliviensis and I. araguaiaensis) regarding its level of restricted distribution and morph-genetics differences. For the Committee on Taxonomy of the Society for Marine Mammalogy, the specific status of the proposed species relies on further knowledge on morphology, ecology, and genetics. Given that species-specific status is required for conservation efforts, we described and compared the echolocation clicks of Inia spp., searching for specific differences on their vocalizations. The sounds were captured with a Cetacean Research ™ C54XRS (+3/-20 dB, -185 dB re: 1V/µPa) in Guaviare River (Orinoco basin), Madeira River (Madeira basin), Xingu River (Amazon Basin), and Araguaia River (Tocantins-Araguaia basin). We found significant differences in all analyzed parameters (peak frequency, 3 dB bandwidth, 10 dB bandwidth and inter-click interval) for all species and subspecies. Differences in acoustical parameters of clicks are mainly related to the animal's internal morphology, thus this study may potentially support with information for the species-level classification mostly of I. araguaiaensis (the Araguaian boto). Classifying the Araguaian boto separately from I. geoffrensis has important implications for the species in terms of conservation status, since it is restricted to a highly impacted river system.

17.
Zootaxa ; 4949(3): zootaxa.4949.3.1, 2021 Mar 26.
Article in English | MEDLINE | ID: mdl-33903329

ABSTRACT

Megascops is the most species-rich owl genus in the New World, with 21 species currently recognized. Phylogenetic relationships within this genus are notoriously difficult to establish due to the considerable plumage similarity among species and polymorphism within species. Previous studies have suggested that the widespread lowland Amazonian M. watsonii might include more than one species, and that the Atlantic Forest endemic M. atricapilla is closely related to the M. watsonii complex, but these relationships are as yet poorly understood. A recently published phylogeny of Megascops demonstrated that M. watsonii is paraphyletic with respect to M. atricapilla and that genetic divergences among some populations of M. watsonii are equal to or surpass the degree of differentiation between some M. watsonii and M. atricapilla. To shed light on the taxonomic status of these species and populations within them, we conducted a multi-character study based on molecular, morphological, and vocal characters. We sequenced three mitochondrial (cytb, CO1 and ND2) and three nuclear genes (BF5, CHD and MUSK) for 49 specimens, covering most of the geographic ranges of M. watsonii and M. atricapilla, and used these sequences to estimate phylogenies under alternative Bayesian, Maximum Likelihood, and multilocus coalescent species tree approaches. We studied 252 specimens and vocal parameters from 83 recordings belonging to 65 individuals, distributed throughout the ranges of M. watsonii and M. atricapilla. We used Discriminant Function Analysis (DFA) to analyze both morphometric and vocal data, and a pairwise diagnostic test to evaluate the significance of vocal differences between distinct genetic lineages. Phylogenetic analyses consistently recovered six statistically well-supported clades whose relationships are not entirely in agreement with currently recognized species limits in M. watsonii and M. atricapilla. Morphometric analyses did not detect significant differences among clades. High plumage variation among individuals within clades was usually associated with the presence of two or more color morphs. By contrast, vocal analyses detected significant differentiation among some clades but considerable overlap among others, with some lineages (particularly the most widespread one) exhibiting significant regional variation. The combined results allow for a redefinition of species limits in both M. watsonii and M. atricapilla, with the recognition of four additional species, two of which we describe here as new. We estimated most cladogenesis in the Megascops atricapilla-M. watsonii complex as having taken place during the Plio-Pleistocene, with the development of the modern Amazonian and São Francisco drainages and the expansion and retraction of forest biomes during interglacial and glacial periods as likely events accounting for this relatively recent burst of diversification.


Subject(s)
Strigiformes , Animals , Bayes Theorem , DNA, Mitochondrial , Genetic Variation , Passeriformes/genetics , Phylogeny , Phylogeography , Strigiformes/classification , Strigiformes/physiology
18.
Zootaxa ; 4951(2): zootaxa.4951.2.1, 2021 Apr 06.
Article in English | MEDLINE | ID: mdl-33903400

ABSTRACT

Allobates trilineatus is the second most geographically widespread species in the genus Allobates, its range extending from northern Ecuador to southern Peru along the Andean foothills of Amazonia and to the east, into Acre, Brazil. However, detailed phenotypic and genetic variation from topotypic specimens is lacking, raising doubts about the identification of specimens in the literature. To solve this problem, we collected 16 topotypic specimens-including male and female adults and juveniles-and associated data such as advertisement calls and tissue samples. Based upon this material, we redescribe the phenotypic variation within A. trilineatus and evaluate its phylogenetic position using a fragment of the mitochondrial gene 16S rDNA. Allobates trilineatus is distinguished from its congeners by its small body size (adult snout-to-vent-length = 14.6-16.6 mm), preserved males with dark gray throat, and gray chest and belly, pale dorsolateral stripe straight and conspicuous, and advertisement call formed by the emission of groups of note-pairs with dominant frequency at 5.06-5.81 kHz. Our phylogenetic results indicate that none of the specimens assigned to this species in previous phylogenetic studies cluster within the clade formed by topotypic samples, except for the sample of one tadpole. Furthermore, our comparison of published phenotypic and genetic data assigned to A. trilineatus with our new data led us to conclude that A. trilineatus as previously recognized was actually a complex of cryptic, closely related species. Although with the data at hand we cannot fully resolve the taxonomy of all sampled populations in previous studies, we provide a new definition and delimitation of A. trilineatus sensu stricto, assign other specimens to different evolutionary units corresponding to candidate species, and flag other important taxonomic issues.


Subject(s)
Anura , Animals , Anura/classification , Anura/genetics , Female , Male , Phylogeny
19.
Zootaxa ; 4948(2): zootaxa.4948.2.8, 2021 Mar 19.
Article in English | MEDLINE | ID: mdl-33757030

ABSTRACT

The southernmost record of the neotropical genus Xenicola is documented. An apparently tiny population of X. dohrni, a species described long ago from southern Brazil without other published records, lives at the shore of the Río de la Plata, 1000 km further south. Perhaps it has been established there by means of floating vegetation. The acoustic communication of this species is also very interesting: The male produces with its minuscule tegmina brief signals with a carrier frequency range between 80 and 100 kHz. The female responds, and the male modifies its song when engaged in a duet. It modifies it further, when the female responds from very close. The paper includes a review of the records of Xenicola species on biodiversity observation platforms.


Subject(s)
Orthoptera , Acoustics , Animals , Argentina , Communication , Female , Male
20.
Pap. avulsos Zool. ; 61: e20216177, 2021. ilus, graf, tab, mapas
Article in English | VETINDEX | ID: vti-31800

ABSTRACT

Scinax comprises more than 120 species which are split in two clades, the S. ruber and the S. catharinae clades. A few species within the S. catharinae clade occur in gallery forests of the Brazilian Cerrado. We here extend the distribution of S. centralis southwards based on new populations sampled in the banks of the Rio Paranaíba, in the borders of Minas Gerais (MG) and Goiás (GO) states, southeastern Brazil. We also provide further data on the species vocalization. Variation was seen among our population and topotypes regarding SVL and call dominant frequency, both likely representing a clinal variation. Our new population of S. centralis represents the first record of the species for the state of Minas Gerais.(AU)


Subject(s)
Animals , Anura/anatomy & histology , Anura/classification , Animal Distribution
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