Navegando por Assunto "Bioacoustics"

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Artigo
Assessing the potential of acoustic indices for protected area monitoring in the Serra do Cipó National Park, Brazil
(Ecological Indicators, 2021) Campos, Ivan Braga; Fewster, Rachel; Truskinger, Anthony; Towsey, Michael; Roe, Paul; Vasques Filho, Demival; Lee, Willian; Gaskett, Anne
Protected areas (PAs) monitoring is a technical bottleneck that limits the implementation of decision-making processes for natural resource and wildlife management. Recent methodological advances make passive acous tic monitoring and associated acoustic index analysis an increasingly suitable method for PAs monitoring. Acoustic indices are mathematical filters that can provide standardised comparative information about the acoustic energy, which can be applied to compare communities. In this study we test whether acoustic indices are sufficiently sensitive to detect differences in the soundscape within each of the four seasons between a PA (the Serra do Cipó National Park, Brazil) and a surrounding farmland area. Statistical analysis of results from 12 acoustic indices is used to identify which of 20 acoustic regions, defined by frequency range and time period, present the greatest differences between the two sites. The soundscapes of the two sites differed most in autumn within the acoustic region 6, representing 05:30 – 09:00am and a range of 0.988–3.609 kHz. This acoustic region exhibited significant differences for all the 12 indices tested. Visual examination of 65 long-duration false-colour (LDFC) spectrograms resulted in the selection of 865 (from 1365) sound files with acoustic events within the range of acoustic region 6. Sonotype analysis of the 865 files showed that the soundscape outside the park is strongly influenced by human activity, with domestic animals rare in the park soundscape (1% of the sound files), but very common in the surrounding farmland environment (63% of the sound files). The main goal of monitoring programmes detecting biodiversity trends across space and time, which is here achieved via passive acoustic monitoring and acoustic indices. This confirms the utility of the techniques used here for PA monitoring, especially for detecting trends in anthropogenic disturbance, which is a common threat to natural habitats in parks and reserves in the tropics.
Artigo
Integrative species delimitation and biogeography of the Rhinella margaritifera species group (Amphibia, Anura, Bufonidae) suggest an intense diversification throughout Amazonia during the last 10 million years
(Systematics and Biodiversity, 2024-08-10) FOUQUET, ANTOINE; FERRÃO, MIQUEIAS; RODRIGUES, MIGUEL T.; WERNECK, FERNANDA P.; PRATES, IVAN; MORAES, LEANDRO J.C.L.; HRBEK, TOMAS; CHAPARRO, JUAN C.; LIMA, ALBERTINA P.; PEREZ, RENATA; PANSONATO, ANDRE; CARVALHO, VINICIUS T.; ALMEIDA, ALEXANDRE P.; GORDO, MARCELO; FARIAS, IZENI P.; MILTO, KONSTANTIN D.; ROBERTO, IGOR J.; ROJAS, ROMMEL R.; RON, SANTIAGO R.; GUERRA, VINICIUS; RECODER, RENATO; CAMACHO, AGUSTIN; MAMANI, LUIS; RAINHA, RAISSA N.; AVILA, ROBSON W.
The accumulation of studies delimiting species in Amazonia has not only shed light on the patterns of its outstanding species richness but also allowed a better understanding of the processes of diversification within this immense region. Nevertheless, vast knowledge gaps remain even for prominent anuran species complexes, such as the Rhinella margaritifera species group. This clade of toads comprises 23 valid species-level taxa, mainly distributed in Amazonia but also in South America’s Dry Diagonal and Atlantic and trans-Andean rainforests. Species boundaries and taxonomy in this group are notoriously complex, with studies suggesting the existence of several unnamed species. Available phylogenetic information suggests an Andean-western Amazonian origin of the group with subsequent diversification within Amazonian lowlands during the last 10 Myr and secondary dispersals into other Neotropical regions. To further test this biogeographic scenario and improve knowledge on species diversity, we used an unprecedentedly large mtDNA sampling (>800 16S sequences) across the clade’s distribution and comprising all but one described species. We delimited 54 Molecular Operational Taxonomic Units, which we tested further based on patterns of variation of a nuclear locus and acoustic and morphological data. This approach confirmed the existence of at least 25 candidate species, 19 of which correspond to currently recognized taxa whereas 30 remained ‘unconfirmed’. Our results clarify the taxonomic status of some species but also suggest multiple introgression events that blur some mtDNA-based species boundaries. Lastly, to provide a temporal framework for the clade’s diversification, we generated a time-calibrated phylogenetic tree based on a mitogenomic matrix, which confirmed a Miocene (∼9 Ma) western Amazonian origin and six major clades in the group, each having initially diversified in different regions within Amazonia. Most of these clades have later dispersed throughout Amazonia during the establishment of the modern Amazonian hydrographic system, i.e., in the last 6 Myr.
Texto publicado em jornal
New troglobitic and troglophilic syntopic species of Endecous(Orthoptera, Grylloidea, Phalangopsidae) from a Brazilian cave: a case of sympatric speciation?
(Magnolia Press, 2020) CASTRO-SOUZA, RODRIGO ANTÔNIO; ZEFA, EDISON; LOPES FERREIRA, RODRIGO
Crickets of the genus Endecous (Orthoptera: Grylloidea: Phalangopsidae) are frequently found in caves, in some cases presenting strictly subterranean lifestyle. In addition to the morphological diagnostic characters of the group, bioacoustic and karyotype, also help on delimiting species. Here, we describe two new sympatric species of this genus, which occur in the largest cave of Minas Gerais state, Brazil, using the morphology of phallic complex, the courtship song and karyotype. Moreover, we discuss the criteria used, the troglomorphisms for this genus, as well as hypothesis on the speciation process involving these species.