scholarly journals A food spectrum analysis of three bufonid species (Anura: Bufonidae) from Uttarakhand region of the western Himalaya, India

2019 ◽  
Vol 11 (13) ◽  
pp. 14663-14671
Author(s):  
Vivekanand Bahuguna ◽  
Ashish Kumar Chowdhary ◽  
Shurveer Singh ◽  
Gaurav Bhatt ◽  
Siddhant Bhardwaj ◽  
...  
Keyword(s):  
Spectrum Analysis ◽  
Western Himalaya ◽  
Amphibian Conservation ◽  
Food Spectrum ◽  
Ecological Diversity ◽  
Gut Content ◽  
Wide Range ◽  
Dietary Niche ◽  
Index Of Relative Importance ◽  
Terrestrial Insects

The ecological diversity of insects and its predators like amphibians are important determinants in ecological balance.  A total of 1,222 prey items in 84 specimens were examined to contribute the understanding of the diets of three Duttaphrynus species, viz., himalayanus, melanostictus, and stomaticus from Uttarakhand, the western Himalaya, India.  Gut content analysis of three bufonids revealed acceptance of a wide range of terrestrial insects and other invertebrates as their food.  The index of relative importance indicated that the most important preys were Formicidae, Coleoptera and Orthoptera.  Duttaphrynus melanostictus had the broadest dietary niche breadth, followed by D. himalaynus and D. stomaticus.  The wide prey spectrum well indicates that these species are the generalist and opportunist invertebrate feeder.  Information pertaining to the food spectrum analysis contributes to understanding the ecological roles and used as a baseline data for future successful amphibian conservation and management programs in the Himalayan ecosystem.

scholarly journals Urban rats have less variable, higher protein diets

2018 ◽  
Vol 285 (1889) ◽  
pp. 20181441 ◽  
Author(s):  
E. Guiry ◽  
M. Buckley
Keyword(s):  
Urban Ecology ◽  
Rural Areas ◽  
Urban Areas ◽  
Conservation Strategies ◽  
Human Society ◽  
Animal Management ◽  
Wide Range ◽  
Brown Rat ◽  
Dietary Niche ◽  
Urban And Rural Areas

Over the past 1000 years, rats ( Rattus spp.) have become one of the most successful and prolific pests in human society. Despite their cosmopolitan distribution across six continents and ubiquity throughout the world's cities, rat urban ecology remains poorly understood. We investigate the role of human foods in brown rat ( Rattus norvegicus ) diets in urban and rural areas over a 100 year period ( ca AD 1790–1890) in Toronto, Canada using stable carbon ( δ 13 C) and nitrogen ( δ 15 N) isotope analyses of archaeological remains. We found that rat diets from urban sites were of higher quality and were more homogeneous and stable over time. By contrast, in rural areas, they show a wide range of dietary niche specializations that directly overlap, and probably competed, with native omnivorous and herbivorous species. These results demonstrate a link between rodent diets and human population density, providing, to our knowledge, the first long-term dietary perspective on the relative value of different types of human settlements as rodent habitat. This study highlights the potential of using the historical and archaeological record to provide a retrospective on the urban ecology of commensal and synanthropic animals that could be useful for improving animal management and conservation strategies in urban areas.

scholarly journals Latitudinal gradients in intraspecific ecological diversity

2013 ◽  
Vol 9 (6) ◽  
pp. 20130778 ◽  
Author(s):  
Márcio S. Araújo ◽  
Raul Costa-Pereira
Keyword(s):  
Species Diversity ◽  
Latitudinal Gradient ◽  
Latitudinal Gradients ◽  
Ecological Diversity ◽  
Invertebrate Animal ◽  
Niche Variation ◽  
Wide Range ◽  
Global Patterns ◽  
Global Biodiversity ◽  
New Perspective

The increase in the number of species with decreasing latitude is a striking pattern of global biodiversity. An important feature of studies of this pattern up to now has been the focus on species as the fundamental unit of interest, neglecting potential within-species ecological diversity. Here, we took a new perspective on this topic by measuring the degree to which individuals within populations differ in niche attributes across a latitudinal gradient (range: 54.01° S to 69.12° N). We show that 156 populations of 76 species across a wide range of vertebrate and invertebrate animal taxa contain more ecologically diverse assemblages of individuals towards lower latitudes. Our results add a new level of complexity to our understanding of global patterns of biodiversity and suggest the possibility that niche variation is partly responsible for the latitudinal gradients of species diversity.

Review of Data on Diets of Beaked Whales: Evidence of Niche Separation and Geographic Segregation

2003 ◽  
Vol 83 (3) ◽  
pp. 651-665 ◽  
Author(s):  
C.D. MacLeod ◽  
M.B. Santos ◽  
G.J. Pierce
Keyword(s):  
Prey Species ◽  
Stomach Contents ◽  
Published Data ◽  
Niche Separation ◽  
Beaked Whale ◽  
Important Prey ◽  
Wide Range ◽  
Dietary Niche ◽  
Beaked Whales ◽  
Fish Remains

This study reviewed published data on dietary preferences of beaked whales (Ziphiidae) from stomach contents analysis. Detailed data were only available for three of the six beaked whale genera (Hyperoodon, Mesoplodon and Ziphius). Stomach samples of these three beaked whale genera primarily contained cephalopod and fish remains, although some also contained crustaceans. Mesoplodon spp. were found to contain the most fish, with some species containing nothing but fish remains, while the southern bottlenose whale (Hyperoodon planifrons) and Cuvier's beaked whale (Ziphius cavirostris) rarely, if ever, contained fish. Of cephalopods identified, Histioteuthid, Gonatid, Cranchiid and Onychoteuthid species usually contributed most to prey numbers and biomass for all beaked whale genera. There was a wide range of species and families of cephalopods recorded from stomach contents, with no obvious preference for bioluminescent prey species, vertical migrating prey species or prey species with specific body compositions. Whales of the genus Mesoplodon generally contained smaller prey, such as cephalopods under 500 g in weight, compared with other beaked whales. Hyperoodon and Ziphius frequently contained much larger cephalopods with many important prey species having a mean weight of over 1000 g. This suggests that Mesoplodon occupies a separate dietary niche from Hyperoodon and Ziphius, which may be an example of niche segregation. In contrast, Hyperoodon and Ziphius appear to occupy very similar dietary niches but have geographically segregated distributions, with Hyperoodon occupying cold-temperate to polar waters and Ziphius occupying warm-temperate to tropical waters.

scholarly journals Effects of flood regime on the diet of Triportheus curtus (Garman, 1890) in an Amazonian floodplain lake

2011 ◽  
Vol 9 (3) ◽  
pp. 623-628 ◽  
Author(s):  
Jardely de Oliveira Pereira ◽  
Maralina Torres da Silva ◽  
Lisandro Juno Soares Vieira ◽  
Rosemara Fugi
Keyword(s):  
Hydrological Cycle ◽  
Temporal Variations ◽  
Food Resources ◽  
Floodplain Lake ◽  
Taxonomic Identification ◽  
Relative Importance ◽  
Flood Regime ◽  
Index Of Relative Importance ◽  
Terrestrial Insects

We analyzed the diet of Triportheus curtus in Lake Amapá on the Acre River (AC - Brazil), during three distinct phases of the hydrological cycle (pre-flooding, flooding, and post-flooding stages). The flooding occurred between January and June of 2009. Samples were collected monthly from October 2008 through September 2009. After collection (at 19:00, 01:00, 07:00, and 13:00 hs) and taxonomic identification, fish were eviscerated and their stomachs preserved in a 4% formalin solution for later analysis. The diet was evaluated by the Index of Relative Importance (IRI), and temporal variations (pre-flooding, flooding, and post-flooding) in the diet were summarized by an ordination technique (DCA). The diet of T. curtus was comprised of several orders of insects and microcrustaceans. In the pre-flooding stage, more than 62% of the diet consisted of Ostracoda. In the flooding phase, T. curtus fed mainly on Chaoboridae larvae (Diptera) (44.3%) and terrestrial insects (fragments) (33.7%). In the post-flooding phase, Chaoboridae comprised 80% of the diet. These results indicate that the utilization of food resources by T. curtus was variable, changing with alterations in the availability of resources, as influenced by the hydrological cycle. The population of T. curtus proved to be opportunistic, changing its diet in the course of the hydrological cycle.

scholarly journals Validating the automation of different measures of high temperature tolerance of small terrestrial insects

2021 ◽  
Author(s):  
Heidi J. MacLean ◽  
Jonas Hjort Hansen ◽  
Jesper Givskov Sorensen
Keyword(s):  
Thermal Tolerance ◽  
Motion Tracking ◽  
Thermal Adaptation ◽  
Temperature Tolerance ◽  
Temperature Acclimation ◽  
Phenotypic Data ◽  
Automated Method ◽  
Starvation Tolerance ◽  
Wide Range ◽  
Terrestrial Insects

Accurately phenotyping numerous test subjects is essential for most experimental research. Collecting such data can be tedious or time-consuming, and can be biased or limited by manual observations. The thermal tolerance of small ectotherms is a good example of this type of phenotypic data, and it is widely used to investigate thermal adaptation, acclimation capacity and climate change resilience of small ectotherms. Here, we present the results of automatically generated thermal tolerance data using motion tracking on video recordings using two Drosophila species and temperature acclimation to create variation in thermal tolerances and two different heat tolerance assays. We find similar effect sizes of acclimation and hardening responses between manual and automated approaches, but different absolute tolerance estimates. This discrepancy likely reflects both technical differences and the behavioral cessation of movement rather than physiological failure measured in other assays. We conclude that both methods generate biological meaningful results, which reflect different aspects of the thermal biology, find no evidence of inflated variance in the manually scored assays, but find that automation can increase throughput without compromising quality. Further we show that the method can be applied to a wide range of arthropod taxa. We suggest that our automated method is a useful example of through-put phenotyping, and suggest this approach might be applied to other tedious laboratory traits, such as desiccation or starvation tolerance, with similar benefits to through-put. However, the interpretation and potential comparison to results using different methodology rely on thorough validation of the assay and the involved biological mechanism.

scholarly journals Igneous Rock Associations 21. The Early Permian Panjal Traps of the Western Himalaya

2016 ◽  
Vol 43 (4) ◽  
pp. 251 ◽  
Author(s):  
J. Gregory Shellnutt
Keyword(s):  
Volcanic Rocks ◽  
Crustal Contamination ◽  
Western Himalaya ◽  
Ocean Basin ◽  
Early Permian ◽  
Basaltic Rocks ◽  
Wide Range ◽  
Silicic Volcanic ◽  
Felsic Volcanic ◽  
Sea Floor Spreading

The Early Permian (290 Ma) Panjal Traps are the largest contiguous outcropping of volcanic rocks associated with the Himalayan Magmatic Province (HMP). The eruptions of HMP-related lava were contemporaneous with the initial break-up of Pangea. The Panjal Traps are primarily basalt but volumetrically minor intermediate and felsic volcanic rocks also occur. The basaltic rocks range in composition from continental tholeiite to ocean-floor basalt and nearly all have experienced, to varying extent, crustal contamination. Uncontaminated basaltic rocks have Sr–Nd isotopes similar to a chondritic source (ISr = 0.7043 to 0.7073; eNd(t) = 0 ± 1), whereas the remaining basaltic rocks have a wide range of Nd (eNd(t) = –6.1 to +4.3) and Sr (ISr = 0.7051 to 0.7185) isotopic values. The calculated primary melt compositions of basalt are picritic and their mantle potential temperatures (TP ≤ 1450°C) are similar to ambient mantle rather than anomalously hot mantle. The silicic volcanic rocks were likely derived by partial melting of the crust whereas the andesitic rocks were derived by mixing between crustal and mantle melts. The Traps erupted within a continental rift setting that developed into a shallow sea. Sustained rifting created a nascent ocean basin that led to sea-floor spreading and the rifting of microcontinents from Gondwana to form the ribbon-like continent Cimmeria and the Neotethys Ocean.RÉSUMÉLes Panjal Traps du début Permien (290 Ma) constituent le plus grand affleurement contigu de roches volcaniques associées à la province magmatique de himalayienne (HMP). Les éruptions de lave de type HMP étaient contemporaines de la rupture initiale de la Pangée. Les Panjal Traps sont essentiellement des basaltes, mais on y trouve aussi des roches volcaniques intermédiaires et felsiques en quantités mineures. La composition de ces roches basaltiques varie de tholéiite continentale à basalte de plancher océanique, et presque toutes ont subi, à des degrés divers, une contamination de matériaux crustaux. Les roches basaltiques non contaminées ont des contenus isotopiques Sr–Nd similaires à une source chondritique (Isr = 0,7043 à 0,7073; eNd (t) = 0 ± 1), alors que les roches basaltiques autres montrent une large gamme de valeurs isotopiques en Nd (eNd (t) = –6,1 à +4,3) et Sr (Isr = de 0,7051 à 0,7185). Les compositions de fusion primaire calculées des basaltes sont picritiques et leurs températures potentielles mantelliques (TP de ≤ 1450°C) sont similaires à la température ambiante du manteau plutôt que celle d’un manteau anormalement chaud. Les roches volcaniques siliciques dérivent probablement de la fusion partielle de la croûte alors que les roches andésitiques proviennent du mélange entre des matériaux de fusion crustaux et mantelliques. Les Traps ont fait irruption dans un contexte de rift continental qui s’est développé dans une mer peu profonde. Un rifting soutenu a créé un début de bassin océanique lequel conduit à une expansion du fond océanique et au rifting de microcontinents tirés du Gondwana pour former le continent rubané de Cimméria et l'océan Néotéthys.

Light pollution: A landscape-scale issue requiring cross-realm consideration

2021 ◽  
Author(s):  
Mariana Mayer-Pinto ◽  
Theresa M. Jones ◽  
Stephen E. Swearer ◽  
Kylie A. Robert ◽  
Damon Bolton ◽  
...  
Keyword(s):  
Species Interactions ◽  
Management Practices ◽  
Management Strategies ◽  
Integrated Approach ◽  
Life Cycles ◽  
Light Pollution ◽  
Professional Networks ◽  
Wide Range ◽  
Holistic Understanding ◽  
Terrestrial Insects

Terrestrial, marine, and freshwater realms are inherently linked through ecological, biogeochemical and/or physical processes. An understanding of these connections is critical to optimise management strategies and ensure the ongoing resilience of ecosystems. Artificial light at night (ALAN) is a global stressor that can profoundly affect a wide range of organisms and habitats and impact multiple realms. Despite this, current management practices for light pollution rarely consider connectivity between realms. Here we discuss the ways in which ALAN can have cross-realm impacts and provide case studies for each example discussed. We identified three main ways in which ALAN can affect two or more realms: 1) impacts on species that have life cycles and/or stages on two or more realms, such as diadromous fish that cross realms during ontogenetic migrations and many terrestrial insects that have juvenile phases of the lifecycle in aquatic realms; 2) impacts on species interactions that occur across realm boundaries, and 3) impacts on transition zones or ecosystems such as mangroves and estuaries. We then propose a framework for cross-realm management of light pollution and discuss current challenges and potential solutions to increase the uptake of a cross-realm approach for ALAN management. We argue that the strengthening and formalisation of professional networks that involve academics, lighting practitioners, environmental managers and regulators that work in multiple realms is essential to provide an integrated approach to light pollution. Networks that have a strong multi-realm and multi-disciplinary focus are important as they enable a holistic understanding of issues related to ALAN.

DeepHeart

2021 ◽  
Vol 17 (2) ◽  
pp. 1-18
Author(s):  
Xiangmao Chang ◽  
Gangkai Li ◽  
Guoliang Xing ◽  
Kun Zhu ◽  
Linlin Tu
Keyword(s):  
Signal Processing ◽  
Deep Learning ◽  
Spectrum Analysis ◽  
Absolute Error ◽  
Physical Activities ◽  
Motion Artifacts ◽  
Training Data ◽  
Data Set ◽  
Electrocardiogram Signals ◽  
Wide Range

Heart rate (HR) estimation based on photoplethysmography (PPG) signals has been widely adopted in wrist-worn devices. However, the motion artifacts caused by the user’s physical activities make it difficult to get the accurate HR estimation from contaminated PPG signals. Although many signal processing methods have been proposed to address this challenge, they are often highly optimized for specific scenarios, making them impractical in real-world settings where a user may perform a wide range of physical activities. In this article, we propose DeepHeart, a new HR estimation approach that features deep-learning-based denoising and spectrum-analysis-based calibration. DeepHeart generates clean PPG signals from electrocardiogram signals based on a training data set. Then a set of denoising convolutional neural networks (DCNNs) are trained with the contaminated PPG signals and their corresponding clean PPG signals. Contaminated PPG signals are then denoised by an ensemble of DCNNs and a spectrum-analysis-based calibration is performed to estimate the final HR. We evaluate DeepHeart on the IEEE Signal Processing Cup training data set with 12 records collected during various physical activities. DeepHeart achieves an average absolute error of 1.61 beats per minute (bpm), outperforming a state-of-the-art deep learning approach (4 bpm) and a classical signal processing approach (2.34 bpm).

scholarly journals Trophic niche shifts and phenotypic trait evolution are largely decoupled in Australasian parrots

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Vicente García-Navas ◽  
Joseph A. Tobias ◽  
Manuel Schweizer ◽  
Daniel Wegmann ◽  
Richard Schodde ◽  
...  
Keyword(s):  
Trophic Niche ◽  
Phenotypic Trait ◽  
Dispersal Capacity ◽  
Trait Evolution ◽  
Wide Range ◽  
Niche Shifts ◽  
Dietary Niche ◽  
Evolutionary Trajectories ◽  
Best Fitting ◽  
Trophic Shifts

Abstract Background Trophic shifts from one dietary niche to another have played major roles in reshaping the evolutionary trajectories of a wide range of vertebrate groups, yet their consequences for morphological disparity and species diversity differ among groups. Methods Here, we use phylogenetic comparative methods to examine whether the evolution of nectarivory and other trophic shifts have driven predictable evolutionary pathways in Australasian psittaculid parrots in terms of ecological traits such as body size, beak shape, and dispersal capacity. Results We found no evidence for an ‘early-burst’ scenario of lineage or morphological diversification. The best-fitting models indicate that trait evolution in this group is characterized by abrupt phenotypic shifts (evolutionary jumps), with no sign of multiple phenotypic optima correlating with different trophic strategies. Thus, our results point to the existence of weak directional selection and suggest that lineages may be evolving randomly or slowly toward adaptive peaks they have not yet reached. Conclusions This study adds to a growing body of evidence indicating that the relationship between avian morphology and feeding ecology may be more complex than usually assumed and highlights the importance of adding more flexible models to the macroevolutionary toolbox.

scholarly journals Reconstructing dietary ecology of extinct strepsirrhines (Primates, Mammalia) with new approaches for characterizing and analyzing tooth shape

Paleobiology ◽  
2021 ◽  
pp. 1-20
Author(s):  
Ethan L. Fulwood ◽  
Shan Shan ◽  
Julia M. Winchester ◽  
Tingran Gao ◽  
Henry Kirveslahti ◽  
...  
Keyword(s):  
3D Model ◽  
3D Models ◽  
Tooth Surface ◽  
Ecological Diversity ◽  
Model Quality ◽  
Dietary Adaptation ◽  
Wide Range ◽  
Multinomial Modeling ◽  
Dietary Ecology ◽  
Tooth Form

Abstract The morphological and ecological diversity of lemurs and lorisiformes once rivaled that of the rest of the primate order. Here, we assemble a dataset of 3D models representing the second mandibular molars of a wide range of extant and fossil strepsirrhines encompassing this diversity. We use these models to distill quantitative descriptors of tooth form and then analyze these data using new analytical methods. We employ a recently developed dental topography metric (ariaDNE), which is less sensitive to details of random error in 3D model quality than previously used metrics (e.g., DNE); Bayesian multinomial modeling with metrics designed to measure overfitting risk; and a tooth segmentation algorithm that allows the shapes of disaggregated tooth surface features to be quantified using dental topography metrics. This approach is successful at reclassifying extant strepsirrhine primates to known dietary ecology and indicates that the averaging of morphological information across the tooth surface does not interfere with the ability of dental topography metrics to predict dietary adaptation. When the most informative combination of dental topography metrics is applied to extinct species, many subfossil lemurs and the most basal fossil strepsirrhines are predicted to have been primarily frugivorous or gummivorous. This supports an ecological contraction among the extant lemurs and the importance of frugivory in the origins of crown Strepsirrhini, potentially to avoid competition with more insectivorous and folivorous members of Paleogene Afro-Arabian primate faunas.

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