12 research outputs found
Wild cognition – linking form and function of cognitive abilities within a natural context
Interest in studying cognitive ecology has moved the field of animal cognition into the wild. Animals face many challenges such as finding food and other resources, avoiding and deterring predators and choosing the best mate to increase their reproductive success. To solve these dilemmas, animals need to rely on a range of cognitive abilities. Studying cognition in natural settings is a powerful approach revealing the link between adaptive form and biological function. Recent technological and analytical advances opened up completely new opportunities and research directions for studying animal cognition. Such innovative studies were able to disclose the variety in cognitive processes that animals use to survive and reproduce. Cognition indeed plays a major role in the daily lives of wild animals, in which the integration of many different types of information using a diverse range of cognitive processes enhances fitness
Reproductive notes and larval development of Macrogenioglottus alipioi (Anura: Odontophrynidae) from the northern Atlantic forest
Macrogenioglottus alipioi é uma espécie rara, alocada em um gênero monotípico, habitante da serapilheira de florestas da região Neotropical, com ampla distribuição no leste do Brasil. Apresentamos alguns dados reprodutivos dessa espécie, a partir de uma população encontrada ao norte do rio São Francisco, no nordeste brasileiro. Incluímos informações a respeito do amplexo, desova, cantos de anúncio e de soltura, em conjunto com a descrição do seu desenvolvimento larval. Indivíduos adultos foram observados apenas após chuvas fortes e contínuas, em poça temporária no interior da mata. Machos cantam em coro na margem da poça. O canto de anúncio consiste em uma única nota pulsátil sem diferenças significativas das demais populações da espécie, mas que prontamente difere Macrogenioglottus dos demais Odontophrynidae. O amplexo é do tipo axilar. Uma fêmea depositou 298 ovos pigmentados em um saco plástico. O girino adquire o seu maior tamanho do estágio 39, sendo o maior girino dentre aqueles das demais espécies na família. No final da metamorfose o comprimento rostro–cloacal juvenil é equivalente ao comprimento total do girino em estágio 26–27, indicando um crescimento posmetamórfico substancial até atingir a idade adulta. Também fornecemos dados dos tamanhos dos machos e fêmeas. A peculiaridade de alguns caracteres larvais e, principalmente, de alguns atributos do canto, corrobora a distinção sistemática de Macrogenioglottus.The neotropical monotypic genus Macrogenioglottus, described to enclose M. alipioi, is a forest leaf litter frog with a wide geographic distribution in eastern Brazil, despite being considered a rare species. Herein, we present some reproductive data of this species from a population of the north of the São Francisco River, Northeastern Brazil. We present information on the amplexus, egg clutch, advertisement, and release calls, along with a description of its larval development. Adults were observed only after heavy and continuous rains, in a temporary pond located inside the forest. Males call in chorus at the edge of the pond. The advertisement call consists of a pulsatile single note, with no substantial variation in relation to the other population of the species, but which promptly differs this genus from the remaining Odontophrynidae. The amplexus is axillary. One female deposited 298 pigmented eggs in a plastic bag. The tadpole reaches its larger size at Stage 39, being the largest tadpole within the family. At the end of metamorphosis, the froglet snout–vent length is equivalent to tadpole total length at stage 26–27, indicating substantial postmetamorphic growth until adulthood. Data on body size of males and females are also provided. The uniqueness of some larval traits and mainly on some call attributes supports the systematic distinction of Macrogenioglottus
Evolutionary trade-offs between testes size and parenting in Neotropical glassfrogs.
In males, large testes size signifies high sperm production and is commonly linked to heightened sperm competition levels. It may also evolve as a response to an elevated risk of sperm depletion due to multiple mating or large clutch sizes. Conversely, weapons, mate or clutch guarding may allow individuals to monopolize mating events and preclude sperm competition, thereby reducing the selection of large testes. Herein, we examined how paternal care, sexual size dimorphism (SSD), weaponry and female fecundity are linked to testes size in glassfrogs. We found that paternal care was associated with a reduction in relative testes size, suggesting an evolutionary trade-off between testes size and parenting. Although females were slightly larger than males and species with paternal care tended to have larger clutches, there was no significant relationship between SSD, clutch size and relative testes size. These findings suggest that the evolution of testes size in glassfrogs is influenced by sperm competition risk, rather than sperm depletion risk. We infer that clutch guarding precludes the risk of fertilization by other males and consequently diminishes selective pressure for larger testes. Our study highlights the prominent role of paternal care in the evolution of testes size in species with external fertilization
Predation on Dermophis sp. (Gymnophiona: Dermophiidae) by Bothrops asper (Serpentes: Viperidae) in La Gamba Field Station, Costa Rica
Two new glassfrogs (Centrolenidae: Hyalinobatrachium) from Ecuador, with comments on the endangered biodiversity of the Andes.
Background
The Tropical Andes is the world's most biodiverse hotspot. This region contains >1,000 amphibian species, more than half of which are endemic. Herein we describe two new glassfrog species (Centrolenidae: Hyalinobatrachium) that we discovered within relatively unexplored and isolated localities of the Ecuadorian Andes.
Methods
We employed morphological, acoustic, and molecular methods to test the hypothesis that Hyalinobatrachium mashpi sp. nov and H. nouns sp. nov. are species new to science. Following standard methods, we generated mitochondrial sequences (16S) of 37 individuals in the genus Hyalinobatrachium. We inferred the phylogenetic relationships of the two new species in comparison to all other glassfrogs using Maximum Likelihood. In addition to describing the call of H. mashpi sp. nov., we performed a discriminant analysis of principal components (DAPC) with the advertisement call characteristics of several congeners.
Results
Based on an integrative taxonomy approach, we describe two new species. Morphological traits and the inferred phylogeny unambiguously place the new taxa in the genus Hyalinobatrachium. Both species are distinguished from other glassfrogs mainly by their dorsal coloration (i.e., dorsum lime green with small light yellow spots, head usually with interorbital bar) and transparent pericardium (i.e., the heart is visible through the ventral skin). The new species exhibit a high morphological similarity (i.e., cryptic) and occur within relatively close geographical proximity (closest aerial distance = 18.9 km); however, their uncorrected p distance for the mitochondrial gene 16S is 4.6-4.7%, a value that greatly exceeds the genetic distance between closely related species of centrolenid frogs. The DAPC revealed that the advertisement call of H. mashpi sp. nov. is acoustically distinct.
Discussion
Our findings are congruent with several previous studies that report a high degree of endemism in the Toisán mountain range, which appears to be isolated from the main Andean cordillera for some amphibian groups. We recommend that both H. mashpi sp. nov. and H. nouns sp. nov. be listed as Endangered, following IUCN criteria. These new species provide another example of cryptic diversity in the Andes-further evidence that the region fosters much more biodiversity than we have the resources to catalog. Threatened by mining and other exploitative industries, these glassfrogs and many other yet-to-be-discovered Andean species highlight the dire need for effective conservation measures-especially in northwestern Ecuador
Preliminary inventory of the anuran fauna of the Mata Estrela Private Natural Heritage Reserve, in the Atlantic Forest of the State of Rio Grande do Norte, Brazil
Tropical regions harbor the highest amphibian biodiversity, nevertheless, information on species composition is lacking in most areas yet these baseline data are essential to guide conservation strategies. The goal of the present study was to survey the anurans of a Private Natural Heritage Reserve named Mata Estrela, a fragment of about 26 km2 in the Northern Atlantic Forest, Brazil. The study was carried out as an active census in June 2015. We found 27 anuran species assigned to five families: Bufonidae (2 spp.), Craugastoridae (1 sp.), Hylidae (11 spp.), Leptodactylidae (12 spp.) and Phyllomedusidae (1 sp.). All species are widespread in the Atlantic forest as well as in other South American ecoregions. Descriptions of local diversity such as this one are a fundamental baseline for conservation work and are especially needed in the northern limits of the Atlantic forest, for which there is still a huge lack of biological knowledge.Asociación Herpetológica Argentin
Seasonality, environmental factors, and host behavior linked to disease risk in stream-dwelling tadpoles
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The aquatic pathogen Batrachochytrium dendrobatidis (Bd) can cause declines in amphibian populations and species extinctions worldwide. In tadpoles, epizootic events have not been reported; however, there is a possibility for rapid spread of disease in water. Here, we quantified Bd infection dynamics in tadpoles from two streams in the northeastern Atlantic forest of Brazil. Bd prevalence varied seasonally and increased during the rainy season. Aplastodiscus sibilatus and Proceratophrys renalis tadpoles were Bd positive in both seasons, whereas Agalychnis granulosa tadpoles were Bd positive only during the rainy season. Bd prevalence was higher in A. sibilatus than in A. granulosa and P. renalis. We found that larger individuals have a higher probability of being Bd positive, independent of the developmental stage. Moreover, we found that canopy cover, water flow, water temperature, water depth, and pH were associated with Bd prevalence. Our results highlight the fact that tadpoles can serve as pathogen reservoirs; therefore, monitoring anuran larvae populations in these habitats can enhance the impact assessment of this pathogen in biodiversity hot spots.The aquatic pathogen Batrachochytrium dendrobatidis (Bd) can cause declines in amphibian populations and species extinctions worldwide. In tadpoles, epizootic events have not been reportedhowever, there is a possibility for rapid spread of disease in72298106FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNQP - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)2011/51694-72014/23388-7302589/2013-9405285/2013-
Ecological functions of neotropical amphibians and reptiles: a review
Amphibians and reptiles (herps) are the most abundant and diverse vertebrate taxa in tropical ecosystems. Nevertheless, little is known about their role in maintaining and regulating ecosystems functions and, by extension, their potential value for supporting ecosystems services. Here, we review research on the ecological functions of Neotropical herps, in different sources (the bibliographic databases, book chapters, etc.). A total of 167 Neotropical herpetology studies published over the last four decades (1970 to 2014) were reviewed, providing information on more than 100 species that contribute to at least five categories of ecological functions: i) nutrient cycling; ii) bioturbation; iii) pollination; iv) seed dispersal, and v) energy flow through ecosystems and the mechanisms behind these, through the study of functional traits and analysis of ecological processes. Many of these functions provide key ecosystems, such as biological pest control, seed dispersal and water quality. By knowing and understanding the functions that perform the herps in ecosystems, management plans for cultural landscapes, restoration or recovery projects of landscapes that involve aquatic and terrestrial systems, development of comprehensive plans and detailed conservation of species and ecosystems may be structured in a more appropriate way. Besides information gaps identified in this review, this contribution explores these issues in terms of better understanding of key questions in the study of ecosystem services and biodiversity and, also, of how these services are generated
Ecological functions of neotropical amphibians and reptiles: a review
Amphibians and reptiles (herps) are the most abundant and diverse vertebrate taxa in tropical ecosystems. Nevertheless, little is known about their role in maintaining and regulating ecosystems functions and, by extension, their potential value for supporting ecosystems services. Here, we review research on the ecological functions of Neotropical herps, in different sources (the bibliographic databases, book chapters, etc.). A total of 167 Neotropical herpetology studies published over the last four decades (1970 to 2014) were reviewed, providing information on more than 100 species that contribute to at least five categories of ecological functions: i) nutrient cycling; ii) bioturbation; iii) pollination; iv) seed dispersal, and v) energy flow through ecosystems and the mechanisms behind these, through the study of functional traits and analysis of ecological processes. Many of these functions provide key ecosystems, such as biological pest control, seed dispersal and water quality. By knowing and understanding the functions that perform the herps in ecosystems, management plans for cultural landscapes, restoration or recovery projects of landscapes that involve aquatic and terrestrial systems, development of comprehensive plans and detailed conservation of species and ecosystems may be structured in a more appropriate way. Besides information gaps identified in this review, this contribution explores these issues in terms of better understanding of key questions in the study of ecosystem services and biodiversity and, also, of how these services are generated