Diversity of anura amphibians in an anthropic lake in the state of Paraíba, Brazil: distribution and temporal variation

The Caatinga is highly heterogeneous, many species being found in their regions. Much of anurofauna this area is commonly found in many open environments. In the present study both the diversity and the temporal occurrence of frogs were determined to Bela Vista Lagoon, located in the municipality of Cuité, Paraíba. 4 areas for sampling were marked, these being covered slowly by hiking. The naturalistic observations were conducted from May 2012 until April 2013 Methods of visual and auditory search were used to simultaneously capture and frequency of species. 6 frog species belonging to 4 genera were found distributed in three families: Bufonidae (2 species), Hylidae (2 species) and Leptodactylidae (2 species). Site 1 showed a wealth of three species, the other areas had a wealth equivalent of 5 species each. The anurofauna recorded high occupancy presented to water bodies and low associations zones altered by man. Nonparametric estimators, calculated for the 36 surveys for the pond Bela Vista, not reached its asymptote, but the Bootstrap model showed a tendency toward stabilization. Among the four sampled areas, Area 2 was the one with the highest diversity, areas 3 and 4 presented the lowest diversity, this fact being related to high dominance of species Rinnella jimi. Regarding the temporal distribution, amphibians showed up influenced by temperature and rainfall record for the region.

Enhanced loss of retinoic acid network genes in Xenopus laevis achieves a tighter signal regulation

Retinoic acid (RA) is a major regulatory signal during embryogenesis produced from vitamin A (retinol) by an extensive, autoregulating metabolic and signaling network to prevent fluctuations that result in developmental malformations. Xenopus laevis is an allotetraploid hybrid frog species whose genome includes L (long) and S (short) chromosomes from the originating species. Evolutionarily, the X. laevis subgenomes have been losing either L or S homoeologs in about 43% of genes to generate singletons. In the RA network, out of the 47 genes, about 46% have lost one of the homoeologs, like the genome average. In contrast, RA metabolism genes from storage (retinyl esters) to retinaldehyde production exhibit enhanced gene loss with 75% singletons out of 28 genes. The effect of this gene loss on RA signaling autoregulation was studied. Employing transient RA manipulations, homoeolog gene pairs were identified in which one homeolog exhibits enhanced responses or looser regulation than the other, while in other pairs both homoeologs exhibit similar RA responses. CRISPR/Cas9 targeting of individual homoeologs to reduce their activity supports the hypothesis where the RA metabolic network gene loss results in tighter network regulation and more efficient RA robustness responses to overcome complex regulation conditions.

Ekstraksi Fitur Tekstur dan Warna pada Kulit Katak Menggunakan GLCM dan Momen Warna

Anura is an order in the Amphibian class consisting of frogs and toads. Anura is very important in the ecosystem, especially its role as part of the food chain. Anura's main role is to maintain the balance of the ecosystem and as a bioindicator agent for changing environmental conditions such as water pollution, habitat destruction, disease and parasites, and climate change. This research applies digital image processing technology which is expected to assist in detecting types of frogs based on color and texture. This research uses 5 types of frogs, namely kongkang gading, kongkang poison, striped trees, small trees and flying trees with 20 images of each type of frog. This research uses the color feature extraction methods such Color Moment and texture extraction GLCM (Gray Level Co-occurance Matrix), then classified using K-Star. The results of the K-Star performance evaluation to classify the 5 types of frogs obtained the Accuracy (Acc) value of 0.93, Precision (Prec) of 0.94, Recall (Rec) of 0.93 and F-measure of 0.93. So that the classification results of frog species on texture and color feature extraction using the GLCM method and the Color Moment with the K-Star classification method have high performance and can work well.

Total Synthesis of Decahydroquinoline Poison Frog Alkaloids ent-cis-195A and cis-211A

The total synthesis of two decahydroquinoline poison frog alkaloids ent-cis-195A and cis-211A were achieved in 16 steps (38% overall yield) and 19 steps (31% overall yield), respectively, starting from known compound 1. Both alkaloids were synthesized from the common key intermediate 11 in a divergent fashion, and the absolute stereochemistry of natural cis-211A was determined to be 2R, 4aR, 5R, 6S, and 8aS. Interestingly, the absolute configuration of the parent decahydroquinoline nuclei of cis-211A was the mirror image of that of cis-195A, although both alkaloids were isolated from the same poison frog species, Oophaga (Dendrobates) pumilio, from Panama.

The process of discovery in and new species from northern Peru, Cerro Colán, Department Amazonas, Province Bagua

A review of discoveries of plants and animals by a 1978 expedition from Louisiana State University to Peru is presented. Genesis of this study was owing to the senior author’s observation of unusually high species richness in Araceae among a collection of plants made in northern Peru. A subsequent review showed that the region was rich in many ways. Determinations to date include 983 species belonging to 513 genera and 145 families of which 81 species are endemic. Included are 59 plant taxa new to science described elsewhere. Eleven aroids (Araceae) from northern Peru are described and illustrated as new. Some records represent new taxa described from voucher specimens independently collected by botanists at prior or later dates and different localities. A collection was assigned the nov. sp. category of noteworthiness if Tropicos database (http://www.tropicos.org) showed either the Alwyn H. Gentry, et al. and or the Philip J. Barbour accession to be the first such collection known. Specimen searches in Tropicos by senior collector as Philip Barbour and separately by Gentry and constrained by appropriate dates revealed 1687 independent determined voucher specimens of which 1545 are noteworthy (92%) by the designated categories. Noteworthy categories are described and presented in appendices 2 and 3. Extralimital plant distribution records are not described here. Four new bird species/subspecies and seven new frog species were discovered on this expedition. It is important to note that after only 42 years much of the region where many of these discoveries were made is now largely devoid of natural vegetation. Appendix 4 provides detailed descriptions of habitat on Cerro Colán as recent as 2017. This study is a reminder that areas newly opened for exploration should be thoroughly and quickly studied to capture the greatest scientific benefit. It shows how much could be attained in a small span of time by a small but dedicated group of biologists.

Detecting Bird and Frog Species Using Tropical Soundscape

In the tropical jungle, hearing a species is considerably simpler than seeing it. The sounds of many birds and frogs may be heard if we are in the woods, but the bird cannot be seen. It is difficult in this these circumstances for the expert in identifying the many types of insects and harmful species that may be found in the wild. An audio-input model has been developed in this study. Intelligent signal processing is used to extract patterns and characteristics from the audio signal, and the output is used to identify the species. Sound of the birds and frogs vary according to their species in the tropical environment. In this research we have developed a deep learning model, this model enhances the process of recognizing the bird and frog species based on the audio features. The model achieved a high level of accuracy in recognizing the birds and the frog species. The Resnet model which includes block of simple and convolution neural network is effective in recognizing the birds and frog species using the sound of the animal. Above 90 percent of accuracy is achieved for this classification task. Keywords: Bird Frog Detection, Neural Network, Resnet, CNN.

Conserved chromatin and repetitive patterns reveal slow genome evolution in frogs

Frogs are an ecologically diverse and phylogenetically ancient group of living amphibians that include important vertebrate cell and developmental model systems, notably the genus Xenopus. Here we report a high-quality reference genome sequence for the western clawed frog, Xenopus tropicalis, along with draft chromosome-scale sequences of three distantly related emerging model frog species, Eleutherodactylus coqui, Engystomops pustulosus and Hymenochirus boettgeri. Frog chromosomes have remained remarkably stable since the Mesozoic Era, with limited Robertsonian (i.e., centric) translocations and end-to-end fusions found among the smaller chromosomes. Conservation of synteny includes conservation of centromere locations, marked by centromeric tandem repeats associated with Cenp-a binding, surrounded by pericentromeric LINE/L1 elements. We explored chromosome structure across frogs, using a dense meiotic linkage map for X. tropicalis and chromatin conformation capture (HiC) data for all species. Abundant satellite repeats occupy the unusually long (~20 megabase) terminal regions of each chromosome that coincide with high rates of recombination. Both embryonic and differentiated cells show reproducible association of centromeric chromatin, and of telomeres, reflecting a Rabl configuration similar to the "bouquet" structure of meiotic cells. Our comparative analyses reveal 13 conserved ancestral anuran chromosomes from which contemporary frog genomes were constructed.

Fitness consequences of targeted gene flow to counter impacts of drying climates on terrestrial-breeding frogs

Targeted gene flow (TGF) could bolster the adaptive potential of isolated populations threatened by climate change, but could also lead to outbreeding depression. Here, we explore these possibilities by creating mixed- and within-population crosses in a terrestrial-breeding frog species threatened by a drying climate. We reared embryos of the crawling frog (Pseudophryne guentheri) on wet and dry soils and quantified fitness-related traits upon hatching. TGF produced mixed outcomes in hybrids, which depended on crossing direction (origin of gametes from each sex). North-south crosses led to low embryonic survival if eggs were of a southern origin, and high malformation rates when eggs were from a northern population. Conversely, east-west crosses led to one instance of hybrid vigour, evident by increased fitness and desiccation tolerance of hybrid offspring relative to offspring produced from within-population crosses. These contrasting results highlight the need to experimentally evaluate the outcomes of TGF for focal species across generations prior to implementing management actions.