Rhinella icterica and Rhinella ornata (Anura: Bufonidae) tadpoles do not recognise siblings

2021 ◽  
pp. 214-220
Author(s):  
Alexandre Polettini Neto

Benefits conferred to animals living in groups may be greater if groups are formed by relatives rather than non-relatives, because cooperating with relatives increases the probability of their own genes being passed on to group offspring (inclusive fitness). Non-social aggregations are formed in response to environmental characteristics, while social aggregations are formed from the attraction among individuals. The attraction or repulsion between individuals is mediated by recognition mechanisms, which mediate important ecological processes and behaviours. Here, we conducted laboratory experiments to test if tadpoles of two sympatric bufonids, Rhinella icterica and R. ornata, are able to recognise siblings. We collected eggs of the two species in the field and raised them in laboratory settings, according to three different methods: siblings and non-siblings reared in separated containers; siblings and non-siblings reared in the same container separated by a plastic net; and eggs from the same spawn reared separately, each one in an individual container. Later, we tested if tadpoles could choose between groups of siblings and non-siblings. The results indicate that tadpoles of neither species were able to discriminate between siblings and non-siblings, regardless of the rearing methods. Therefore, kinship is less important than environmental factors in tadpole aggregation behaviour of these species, and it may be dependent on the balance between costs and benefits. Our results can be used as a start point to better understand tadpole aggregation behaviour and recognition mechanisms in these species.

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
◽  

Abstract Autism is a set of heterogeneous neurodevelopmental conditions, characterised by early-onset difficulties in social communication and restricted, repetitive behaviour and interests. The worldwide population prevalence is about 1% with an increasing incidence and prevalence rates. Autism affects more male than female individuals, and comorbidity is common (>70% have concurrent conditions). Determinants of these changes in incidence and prevalence rates may also be related to exposure to environmental factors and to modifications in diagnostic concepts and criteria. In spite of the uncertainty in determinants of incidence of autisms, there is evidence that environmental characteristics play a significant role both as autism risk factors and as potential obstacles that influence the capabilities of autonomously and fully “using” everyday spaces. The workshop aims to provide a framework on risk factors of autism and explore the relationship with the built environment, focusing on the quality of the everyday spaces and projecting the effects that it could have in the long term on achieving a desirable level of quality of life. The 11th Sustainable Development Goals of United Nations “Make cities inclusive, safe, resilient and sustainable” underlines the necessity of designing policies and projects acting to enhance and promote healthy cities and communities by addressing the needs of the most vulnerable groups of inhabitants. Herewith we bring together the discipline of Public Health and Urban Design to promote an interdisciplinary debate on a little explored topic investigating how the approaches adopted during childhood to promote the wellbeing of people with ASD can be related or strengthen by focusing also on built environment design intervention to pursue and reach the same objectives even during adulthood. The workshop will consist of four presentations. The first focuses on giving an overview on current knowledge of intervention for people with autism, presenting also criteria for evidence-based interventions. The second explores the relationship between autism and built environment by providing an exhaustive framework of the available research literature in order to identify a first set of spatial requirements for autism friendly cities. The third examines the impact of built environment on ASD users with the aim of developing a specific evaluation tool for healthcare spaces and best practices formulation according to the specific sensorial hypo- or hyper-activation of people with autism. Finally, the fourth reports the results of a two years Research & Development project called “GAP REDUCE” finalized at developing an Assistive Technology tool to support people with ASD, adult and high-functioning, to plan urban itineraries towards daily destinations. Key messages World's incidence of autism is about 1% with an increasing incidence whose determining rates may also be related to environmental factors and to modifications in diagnostic concepts and criteria. Environmental characteristics play a significant role also as potential obstacles that influence the capabilities of people with autism of autonomously and fully “using” everyday spaces.


2014 ◽  
Vol 11 (6) ◽  
pp. 1179-1186 ◽  
Author(s):  
Kathryn C. Nesbit ◽  
Thubi A. Kolobe ◽  
Sandra H. Arnold ◽  
Susan B. Sisson ◽  
Michael P. Anderson

Background:The purpose of this study was to determine how proximal (home) and distal (neighborhood) environmental characteristics interact to influence obesity in early and middle adolescents.Methods:This was a descriptive, cross-sectional study using the 2007 National Survey of Children’s Health (NCSH). Participants were 39,542 children ages 11 to 17 years. Logistic regressions were used to examine the relationship between adolescent obesity and environmental factors, the relative strength of these factors, and the influence of age and gender.Results:Proximal environmental factors were stronger correlates of adolescent obesity than distal environmental factors. Sedentary behavior related to TV watching time at home was the strongest correlate of adolescent obesity overall (OR 1.13, 95% CI 1.11–1.15). Parks and playgrounds (OR 0.86, 95% CI 0.08–0.92), as well as recreation centers (OR 0.91, 95% CI 0.85–0.97) were significant distal environmental factor correlates. Girls and middle adolescents were at less risk for obesity than boys and early adolescents (OR 0.51, 95% CI 0.68–0.82; OR 0.75, 95% CI 0.68–0.96).Conclusion:The results of this study reveal the importance of proximal environmental characteristics on adolescent obesity relative to distal environmental characteristics. Obesity intervention strategies for adolescents should target sedentary behavior and opportunities for physical activity with a focus on early adolescents and boys.


2014 ◽  
Vol 60 (6) ◽  
pp. 371-382 ◽  
Author(s):  
María Cecilia Mestre ◽  
Sonia Fontenla ◽  
Carlos A. Rosa

Environmental factors influencing the occurrence and community structure of soil yeasts in forests are not well studied. There are few studies dedicated to Southern Hemisphere soil yeasts populations and even fewer focused on temperate forests influenced by volcanic activity. The present work aimed to study the ecology of soil yeast communities from pristine forests influenced by different environmental factors (precipitation, physicochemical properties of soil, tree species, soil region, and season). The survey was performed in 4 northern Patagonian forests: 2 dominated by Nothofagus pumilio and 2 by Nothofagus antarctica. Yeast communities were described with ecological indices and species accumulation curves, and their association with environmental characteristics was assessed using multivariate analysis. Each forest site showed a particular arrangement of species as a result of environmental characteristics, such as dominant plant species, nutrient availability, and climatic characteristics. Cryptococcus podzolicus was most frequently isolated in nutrient-rich soils, Trichosporon porosum dominated cold mountain forests with low nutrient and water availability in soil, and capsulated yeasts such as Cryptococcus phenolicus dominated forest sites with low precipitation. The present work suggests that environmental factors affecting yeast communities may not be the current soil characteristics but the result of complex interactions of factors including natural disturbances like volcanic activity.


Author(s):  
W. Eifion Jones

At an early stage of an autecological study of Gracilaria verrucosa (Hudson) Papenfuss it seemed possible that the best growth of the plants occurred in places, such as the Achill Sound and the Church Island Channel in the Menai Straits, where, in the absence of heavy wave action, strong currents flowed over the plants. Experiments were carried out, in the sea, to investigate the effect of currents on the growth rate; the apparatus used and described here would probably be suitable for the investigation of current effects on other sedentary marine organisms.These experiments also led to some observations on the effects of illumination on the pigmentation and growth rate of the plants which were supplemented by laboratory experiments. High intensity illumination in the laboratory also demonstrated positive phototropism in the plant.


2017 ◽  
Vol 87 (3) ◽  
pp. 268-288 ◽  
Author(s):  
Susu Liu ◽  
Zheng Ouyang ◽  
Alice M. Chong ◽  
Haitao Wang

Burgeoning evidence has shown that neighborhood environments are related to depressive symptoms in the older population. Older adults living in residential care homes may be more vulnerable to environmental characteristics. The current study sought to understand how institutionalized older adults relate to environmental factors and residential satisfaction in terms of depressive symptoms. Data were collected from a cross-sectional national survey of 1,429 Chinese elders living in residential care homes. The findings reveal that 46.1% of the older Chinese residents living in residential care homes suffered from mild to severe depression. In addition, the current study finds that both environmental factors (e.g., geographic position, air quality, and transportation) and residential satisfaction are negatively associated with depressive symptoms. The findings support that residential satisfaction partially mediate the relationship between exterior environmental characteristics and depressive symptoms.


2007 ◽  
Vol 104 (18) ◽  
pp. 7361-7366 ◽  
Author(s):  
Reinhard Selten ◽  
Massimo Warglien

We investigate in a series of laboratory experiments how costs and benefits of linguistic communication affect the emergence of simple languages in a coordination task when no common language is available in the beginning. The experiment involved pairwise computerized communication between 152 subjects involved in at least 60 rounds. The subjects had to develop a common code referring to items in varying lists of geometrical figures distinguished by up to three features. A code had to be made of a limited repertoire of letters. Using letters had a cost. We are interested in the question of whether a common code is developed, and what enhances its emergence. Furthermore, we explore the emergence of compositional, protogrammatical structure in such codes. We compare environments that differ in terms of available linguistic resources (number of letters available) and in terms of stability of the task environment (variability in the set of figures). Our experiments show that a too small repertoire of letters causes coordination failures. Cost efficiency and role asymmetry are important factors enhancing communicative success. In stable environments, grammars do not seem to matter much, and instead efficient arbitrary codes often do better. However, in an environment with novelty, compositional grammars offer considerable coordination advantages and therefore are more likely to arise.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Alexandre Polettini Neto ◽  
Jaime Bertoluci

Abstract: Tadpoles are able to perceive and discriminate signals from environment and they may use this ability in behaviors and ecological processes. Recognition mechanisms may be involved in schooling by means of attraction among individuals, characterizing a social process. By means of laboratory experiments the present study investigated the presence or absence of attraction to conspecifics in tadpoles of Rhinella icterica and R. ornata, two sympatric species from the Atlantic Forest of southeastern Brazil. We collected eggs of these two species in the field and reared them in laboratory according to two different methods (isolated or in groups of siblings). Tadpoles were submitted to experiments of choice between conspecifics, heterospecifics, and an empty compartment. Rhinella icterica tadpoles preferred to associate with conspecifics rather than R. ornata tadpoles, and we verified this is an innate behavior. Rhinella ornata tadpoles failed to discriminate between conspecifics and R. icterica tadpoles. When submitted to choice between a group of tadpoles of the other species and an empty compartment, R. icterica tadpoles presented random distribution, while R. ornata tadpoles preferred to associate with heterospecifics. Our results indicate R. icterica tadpoles have preference to associate with conspecifics, while R. ornata tadpoles may school indiscriminately. This study contributes for a better understanding of larval anuran social behavior.


2018 ◽  
Vol 285 (1885) ◽  
pp. 20181203 ◽  
Author(s):  
Jan Michels ◽  
Angela Stippkugel ◽  
Mark Lenz ◽  
Kai Wirtz ◽  
Anja Engel

Ocean plastic pollution has resulted in a substantial accumulation of microplastics in the marine environment. Today, this plastic litter is ubiquitous in the oceans, including even remote habitats such as deep-sea sediments and polar sea ice, and it is believed to pose a threat to ecosystem health. However, the concentration of microplastics in the surface layer of the oceans is considerably lower than expected, given the ongoing replenishment of microplastics and the tendency of many plastic types to float. It has been hypothesized that microplastics leave the upper ocean by aggregation and subsequent sedimentation. We tested this hypothesis by investigating the interactions of microplastics with marine biogenic particles collected in the southwestern Baltic Sea. Our laboratory experiments revealed a large potential of microplastics to rapidly coagulate with biogenic particles, which substantiates this hypothesis. Together with the biogenic particles, the microplastics efficiently formed pronounced aggregates within a few days. The aggregation of microplastics and biogenic particles was significantly accelerated by microbial biofilms that had formed on the plastic surfaces. We assume that the demonstrated aggregation behaviour facilitates the export of microplastics from the surface layer of the oceans and plays an important role in the redistribution of microplastics in the oceans.


2018 ◽  
Vol 79 (3) ◽  
pp. 556-565
Author(s):  
Xiaoyi Dong ◽  
Eunhyung Lee ◽  
Yongseok Gwak ◽  
Sanghyun Kim

Abstract Spatio-temporal variation in soil moisture plays an important role in hydrological and ecological processes. In the present study, we investigated the effect of environmental factors on variation in soil moisture at a hillslope scale. The relationships among various environmental factors, including soil properties, topographic indices, and vegetation of a humid forest hillslope, and soil moisture distributions were evaluated based on soil moisture data collected at 18 sampling locations over three seasons (spring, rainy, and autumn) at depths of 10, 30, and 60 cm. In order to evaluate the multi-dimensional data sets without the interaction among factors, the principal component regression (PCR) model was applied to identify the factors controlling the spatio-temporal variation in soil moisture. The effects on soil texture and topography were significant in spring. In addition, clay and sand appeared as critical control factors for the study area in all seasons. The transitional control patterns in the soil moisture profile indicated that the control varied depending on features, such as total amount, intensity, and duration, of rainfall events in spring and during the rainy season. The transitional control pattern for autumn showed that vegetation and local slope controlled transitions in topography.


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