scholarly journals Environmental correlates of internal coloration in frogs vary throughout space and lineages

2017 ◽  
Author(s):  
Lilian Franco-Belussi ◽  
Diogo Borges Provete ◽  
Classius de Oliveira
Keyword(s):  
Temperature Variation ◽  
Species Distribution ◽  
Hormonal Regulation ◽  
Environmental Variables ◽  
Deleterious Effect ◽  
Parietal Peritoneum ◽  
Internal Organs ◽  
Developmental Origin ◽  
Environmental Correlates ◽  
Melanin Coloration

SummaryInternal organs of ectotherms have melanin-containing cells. Several studies analyzed their developmental origin, role in immunity, and hormonal regulation. However, little is known about how environmental variables influence the distribution and quantity of organ coloration. Here, we addressed how environmental variables (temperature, UV, and photoperiod) influence the internal coloration of amphibians after controlling for spatial and phylogenetic autocorrelations. Coloration in all organs was correlated with phylogeny. However, the coloration of the heart, kidneys, and rectum of hylids, R. schneideri, some Leptodactylus, and Proceratophrys were influenced by temperature and photoperiod, whereas that of the testicle, lumbar parietal peritoneum, lungs, and mesenterium of Leiuperinae, Hylodidae, Adenomera, most Leptodactylus were influenced by UVB and temperature variation. Therefore, the amount of internal melanin seems to be a key trait influencing species distribution of frogs throughout space, since it can protect internal organs against the deleterious effect of high UV-B, temperature variation, and photoperiod.SignificanceThe functions of internal coloration in fishes and frogs are little known. Internal pigmentation is commonly altered in fish and the degree of response is correlated with body transparency levels, suggesting possible adaptive functions. Here, we assume that internal melanin has protective functions against UV-B, temperature variation, and photoperiod. Thus it could influence frogs species distribution throughout space. The melanin coloration of each organ was influenced by distinct environmental variables depending on the lineages of species. Our results could direct further studies about the functions of internal coloration.

scholarly journals Environmental correlates for tree occurrences, species distribution and richness on a high-elevation tropical island

AoB Plants ◽  
2015 ◽  
Vol 7 ◽  
pp. plv075 ◽  
Author(s):  
Philippe Birnbaum ◽  
Thomas Ibanez ◽  
Robin Pouteau ◽  
Hervé Vandrot ◽  
Vanessa Hequet ◽  
...  
Keyword(s):  
Species Distribution ◽  
High Elevation ◽  
Tropical Island ◽  
Environmental Correlates

scholarly journals Rediscovery of the endemic gastropod Dianella schlickumi (Gastropoda, Hydrobiidae) and its discrimination from Dianella thiesseana: environmental correlates and implications for their conservation

2018 ◽  
Vol 27 ◽  
pp. 35-58
Author(s):  
Chrysoula Ntislidou ◽  
Canella Radea ◽  
Sinos Giokas ◽  
Martin T. Pusch ◽  
Maria Lazaridou ◽  
...  
Keyword(s):  
Community Structure ◽  
Environmental Variables ◽  
Redundancy Analysis ◽  
Habitat Degradation ◽  
Effective Management ◽  
Environmental Correlates ◽  
Narrow Endemic ◽  
Morphometric Analyses ◽  
Management Plans ◽  
Anatomical Characters

The aquatic snail genus Dianella (Gastropoda: Hydrobiidae) has only two representatives in Greece: Dianellaschlickumi Schütt, 1962 and Dianellathiesseana (Kobelt, 1878). D.schlickumi, a narrow endemic species to Lake Amvrakia (in Aitoloakarnania, western-central Greece), is considered as Critically Endangered (Possibly Extinct, sensu IUCN 2017). Our study confirmed its presence in Lake Amvrakia, where it had not been detected for more than 30 years. We document the unknown anatomical characters based on the D.schlickumi specimens. Moreover, the presence of D.thiesseana in the nearby lakes Trichonis and Lysimachia was also confirmed, while morphometric analyses enabled the discrimination between the two species. Redundancy Analysis revealed conductivity, dissolved oxygen and pH as the main environmental variables related to the above species’ distribution, shaping their community structure. Both Dianella species require urgent conservation measures to be enforced, due to their habitat degradation from human activities, which are limiting and fragmenting their range. For that purpose, effective management plans have to be elaborated and implemented at the mentioned lakes, focusing on the reduction of human pressures and on the improvement of their habitats.

scholarly journals Distribution Pattern of Gymnosperms’ Richness in Nepal: Effect of Environmental Constrains along Elevational Gradients

Plants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 625
Author(s):  
Bikram Pandey ◽  
Nirdesh Nepal ◽  
Salina Tripathi ◽  
Kaiwen Pan ◽  
Mohammed A. Dakhil ◽  
...  
Keyword(s):  
Species Richness ◽  
Distribution Pattern ◽  
Species Distribution ◽  
Environmental Variables ◽  
Environmental Indicators ◽  
Climatic Variables ◽  
Elevation Gradients ◽  
Hypothesis Model ◽  
Richness Pattern ◽  
Richness Patterns

Understanding the pattern of species distribution and the underlying mechanism is essential for conservation planning. Several climatic variables determine the species diversity, and the dependency of species on climate motivates ecologists and bio-geographers to explain the richness patterns along with elevation and environmental correlates. We used interpolated elevational distribution data to examine the relative importance of climatic variables in determining the species richness pattern of 26 species of gymnosperms in the longest elevation gradients in the world. Thirteen environmental variables were divided into three predictors set representing each hypothesis model (energy-water, physical-tolerance, and climatic-seasonality); to explain the species richness pattern of gymnosperms along the elevational gradient. We performed generalized linear models and variation partitioning to evaluate the relevant role of environmental variables on species richness patterns. Our findings showed that the gymnosperms’ richness formed a hump-shaped distribution pattern. The individual effect of energy-water predictor set was identified as the primary determinant of species richness. While, the joint effects of energy-water and physical-tolerance predictors have explained highest variations in gymnosperm distribution. The multiple environmental indicators are essential drivers of species distribution and have direct implications in understanding the effect of climate change on the species richness pattern.

scholarly journals Patagonian bats: new size limits, southernmost localities and updated distribution for Lasiurus villosissimus and Myotis dinellii (Chiroptera: Vespertilionidae)

Mammalia ◽  
2020 ◽  
Vol 84 (2) ◽  
pp. 150-161
Author(s):  
Analía Laura Giménez ◽  
Mauro Ignacio Schiaffini
Keyword(s):  
South America ◽  
Species Distribution ◽  
Environmental Variables ◽  
New Records ◽  
Spatial Scales ◽  
Behavioral Adaptations ◽  
Hoary Bat ◽  
Size Limits

AbstractVespertilionid species are widely distributed in South America. They are highly diverse, with physiological and behavioral adaptations which allow them to extend their distributions into temperate areas. In Patagonia, this family is represented by seven species in three genera (Histiotus, Lasiurus and Myotis). In this study, we analyzed the distribution of two vespertilionid species, Lasiurus villosissimus and Myotis dinellii, including new southernmost records, and their relationship with environmental variables. Two different spatial scales were analyzed: a continental approach for species distribution analyses (South America), and local trapping of bats in northwestern Chubut province, Argentina. We present new southern limits for L. villosissimus and M. dinellii, and included new records for Patagonian bats. The big hoary bat L. villosissimus was recorded as the largest bat inhabiting Patagonia, relating it as a bat mainly inhabiting low, humid and temperate/warm areas. The little yellow bat M. dinellii, instead, is the smallest mammal and the smallest bat recorded in Patagonia to date, related mainly with dry, mid-altitude and temperate/warm areas.

Environmental Correlates of Physical Activity in a Sample of Belgian Adults

2003 ◽  
Vol 18 (1) ◽  
pp. 83-92 ◽  
Author(s):  
Ilse De Bourdeaudhuij ◽  
James F. Sallis ◽  
Brian E. Saelens
Keyword(s):  
Physical Activity ◽  
Public Transportation ◽  
Environmental Variables ◽  
Vigorous Physical Activity ◽  
Moderate Intensity ◽  
Neighborhood Design ◽  
Good Reliability ◽  
Cross Sectional ◽  
Environmental Correlates ◽  
Environment Variables

Purpose. This study investigated the variance in sitting, walking, and moderate and vigorous physical activity explained by neighborhood design and recreational environmental variables above and beyond the variance accounted for by individual demographic variables. Design. Cross-sectional analyses of self-reported survey data. Setting. A random sample of inhabitants of Ghent, Belgium, aged 18–65 years, was drawn. Subjects. Five hundred twenty-one adults completed questionnaires (52.1% response rate). The average age of the sample was 41 years, and 48.2% were female. Measures. A questionnaire developed to assess neighborhood design and recreational environmental variables with a total of 81 items was administered. The environmental questionnaire showed acceptable to good reliability and acceptable validity. The previously validated International Physical Activity Questionnaire (IPAQ) was used to quantify physical activity in the past 7 days. Additional demographic information was also obtained. Results. Regression analyses showed that environmental variables were related to all types of physical activity in both sexes. However, the range of variance explained by the models including demographic and environmental variables was low, only 5% to 13%. Minutes of walking and of moderate-intensity activity were related to quality of sidewalks and accessibility of shopping and public transportation. Vigorous physical activity was related to presence of activity supplies in the home and number of convenient activity facilities outside the home. Conclusions. Both neighborhood design and recreational environment variables had small but significant associations with multiple types of physical activity in a sample of Belgian adults.

Association of Perceived Environmental Characteristics and Participation in Organized and Non-Organized Physical Activities of Adolescents

2009 ◽  
Vol 21 (2) ◽  
pp. 233-239 ◽  
Author(s):  
Jorge Mota ◽  
Marta Almeida ◽  
Rute Santos ◽  
José Carlos Ribeiro ◽  
Maria Paula Santos
Keyword(s):  
Environmental Variables ◽  
Physical Activities ◽  
Organized Activities ◽  
Environmental Perceptions ◽  
Cross Sectional Survey ◽  
Specific Behavior ◽  
Environmental Characteristics ◽  
Cross Sectional ◽  
Environmental Correlates ◽  
Different Dimensions

Specific behavior context such as type of PA (organized vs. nonorganized) might be associated with different environmental correlates. The main goal of this cross-sectional survey was to examine perceived environmental associations with type of adolescents’ physical activity (PA) choices (organized and nonorganized). A sample of this study comprised 425 girls with mean age of 14.5 years-old. Environmental variables and PA were assessed by questionnaire, which allowed to define the type (organized or nonorganized) of PA. No associations were found between environmental perceptions and the participation in organized activities. However, different dimensions of environmental variables such as accessibilities to facilities (p ≤ .05) aesthetics (p ≤ .05) and social environment (p ≤ .05) were associated to girls’ PA participation in nonorganized activities (NOPA). Our findings suggested that some environmental characteristics might play an important role in girls’ NOPA participation.

scholarly journals Cladocera distribution along an environmental gradient on the Cerrado-Amazon ecotone: a preliminary study

2019 ◽  
Vol 31 ◽  
Author(s):  
Leandro Schlemmer Brasil ◽  
Ana Luiza-Andrade ◽  
Tiago Borges Kisaka ◽  
Paulo Ilha ◽  
Francisco Diogo Rocha Sousa
Keyword(s):  
Land Use ◽  
Species Distribution ◽  
Environmental Variables ◽  
Redundancy Analysis ◽  
Environmental Gradient ◽  
Canopy Cover ◽  
Knowledge Gap ◽  
Stream Communities ◽  
Preliminary Study

Abstract: Aim Our objective in this study is to understand Cladocera species distribution along an environmental gradient in forest and cropland landscapes in the southern Amazon. Methods We collected Cladocera communities and environmental variables from five streams and verified their associations with a Redundancy Analysis. Results Acroperus tupinamba, Alonella dadayi e Kisakiellus aweti were mostly associated to sites with higher canopy cover. Anthalona neotropica, Anthalona verrucose and Flavalona iheringula occurred exclusively in site with more thalweg depth. Conclusions If these results are confirmed Cladocera stream communities are affected by changes in land use. Further studies in this line are extremely necessary to reduce this knowledge gap.

scholarly journals Historical disturbances to rivers appear to constrain contemporary distribution of a river-dependent frog

2021 ◽  
Author(s):  
Mark A. Linnell ◽  
Raymond J. Davis
Keyword(s):  
Species Distribution ◽  
Environmental Variables ◽  
Species Distribution Models ◽  
Ensemble Model ◽  
Distribution Models ◽  
Precipitation Frequency ◽  
Historical Distribution ◽  
Large Water ◽  
Source Populations ◽  
Riparian Corridor

AbstractFrogs dependent on lotic environments are sensitive to disturbances that alter the hydrology (e.g., water impoundments), substrate (e.g., debris torrents), and riparian vegetation (e.g., wildfires) of river ecosystems. Although rivers are often very dynamic, disturbances can push environmental baselines outside of narrowly defined ecological tolerances under which a species evolved. Short-lived lotic-dependent organisms, restricted to movements within the water or the riparian corridor, are at risk of local extirpations owing to such disturbances if they fragment and isolate affected populations from recolonizing source populations. In Oregon, USA, the foothill yellow-legged frog (Rana boylii) is at its northernmost range margin and has experienced an approximately 41% range contraction compared to their historical distribution. To inform conservation and management, we used species distribution models to identify environmentally suitable watersheds based on intrinsic baseline environmental variables, and then examined potential effects of human-caused alterations to rivers, including splash dams used to ferry timber downstream prior to 1957, large water impoundments, and adjacency to agricultural croplands. We used machine-learning in program Maxent and three different river layers that varied in extent and location of mapped rivers but contained distinct information to produce species distribution models which we then combined into a single ensemble model. Stream order, annual precipitation, and precipitation frequency were the highest ranked baseline environmental variables in most models. Watersheds with highly suitable baseline conditions in our ensemble model were negatively correlated with anthropogenic disturbances to rivers. Foothill yellow-legged frogs appeared to be sensitive to human-caused disturbances to rivers, perhaps indicative of their narrow ecological tolerance to in-river conditions. We do not anticipate variables in our model to change much through time. Rather, for conservation we identified potential legacy (spash dams) and ongoing human-caused disturbances that are more likely to change conditions for the species in the short- and long-term.

Species Distribution Models (SDM) – A Strategic Tool for Predicting Suitable Habitats for Conserving the Target Species

2017 ◽  
pp. 427-440
Author(s):  
Balaguru Balakrishnan ◽  
Nagamurugan Nandakumar ◽  
Soosairaj Sebastin ◽  
Khaleel Ahamed Abdul Kareem
Keyword(s):  
Species Distribution ◽  
Spatial Data ◽  
Environmental Variables ◽  
Species Distribution Models ◽  
Species Distribution Model ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Target Species ◽  
Distribution Models ◽  
Suitable Habitats

Conservation of the species in their native landscapes required understanding patterns of spatial distribution of species and their ecological connectivity through Species Distribution Models (SDM) by generation and integration of spatial data from different sources using Geographical Information System (GIS) tools. SDM is an ecological/spatial model which combines datasets and maps of occurrence of target species and their geographical and environmental variables by linking various algorithms together, that has been applied to either identify or predict the regions fulfilling the set conditions. This article is focused on comprehensive review of spatial data requirements, statistical algorithms and softwares used to generate the SDMs. This chapter also includes a case study predicting the suitable habitat distribution of Gnetum ula, an endemic and vulnerable plant species using maximum entropy (MaxEnt) species distribution model for species occurrences with inputs from environmental variables such as bioclimate and elevation.

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