scholarly journals Cetaceans as Exemplars of Evolution and Evolutionary Ecology: A Glossary

Oceans ◽  
2020 ◽  
Vol 1 (2) ◽  
pp. 56-76
Author(s):  
Alexander J. Werth
Keyword(s):  
Case Studies ◽  
Evolutionary Biology ◽  
Evolutionary Ecology ◽  
Current Knowledge ◽  
Brute Fact ◽  
Research Studies

Extant cetaceans (whales, dolphins, and porpoises) and their extinct ancestors offer some of the strongest and best-known examples of macroevolutionary transition as well as microevolutionary adaptation. Unlike most reviews of cetacean evolution, which are intended to chronicle the timeline of cetacean ancestry, document the current knowledge of cetacean adaptations, or simply validate the brute fact of evolution, this review is instead intended to demonstrate how cetaceans fittingly illustrate hundreds of specific, detailed terms and concepts within evolutionary biology and evolutionary ecology. This review, arrayed in alphabetical glossary format, is not meant to offer an exhaustive listing of case studies or scholarly sources, but aims to show the breadth and depth of cetacean research studies supporting and investigating numerous evolutionary themes.

scholarly journals Pan-American Lancehead Pit-Vipers: Coagulotoxic Venom Effects and Antivenom Neutralisation of Bothrops asper and B. atrox Geographical Variants

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 78
Author(s):  
Lachlan A. Bourke ◽  
Christina N. Zdenek ◽  
Edgar Neri-Castro ◽  
Melisa Bénard-Valle ◽  
Alejandro Alagón ◽  
...  
Keyword(s):  
Evolutionary Biology ◽  
Current Knowledge ◽  
Clinical Manifestations ◽  
In Vivo Studies ◽  
Factor X ◽  
Clotting Factors ◽  
Bothrops Asper ◽  
Species Specific

The toxin composition of snake venoms and, thus, their functional activity, can vary between and within species. Intraspecific venom variation across a species’ geographic range is a major concern for antivenom treatment of envenomations, particularly for countries like French Guiana that lack a locally produced antivenom. Bothrops asper and Bothrops atrox are the most medically significant species of snakes in Latin America, both producing a variety of clinical manifestations, including systemic bleeding. These pathophysiological actions are due to the activation by the venom of the blood clotting factors Factor X and prothrombin, thereby causing severe consumptive coagulopathy. Both species are extremely wide-ranging, and previous studies have shown their venoms to exhibit regional venom variation. In this study, we investigate the differential coagulotoxic effects on human plasma of six venoms (four B. asper and two B. atrox samples) from different geographic locations, spanning from Mexico to Peru. We assessed how the venom variation of these venom samples affects neutralisation by five regionally available antivenoms: Antivipmyn, Antivipmyn-Tri, PoliVal-ICP, Bothrofav, and Soro Antibotrópico (SAB). The results revealed both inter- and intraspecific variations in the clotting activity of the venoms. These variations in turn resulted in significant variation in antivenom efficacy against the coagulotoxic effects of these venoms. Due to variations in the venoms used in the antivenom production process, antivenoms differed in their species-specific or geographical neutralisation capacity. Some antivenoms (PoliVal-ICP, Bothrofav, and SAB) showed species-specific patterns of neutralisation, while another antivenom (Antivipmyn) showed geographic-specific patterns of neutralisation. This study adds to current knowledge of Bothrops venoms and also illustrates the importance of considering evolutionary biology when developing antivenoms. Therefore, these results have tangible, real-world implications by aiding evidence-based design of antivenoms for treatment of the envenomed patient. We stress that these in vitro studies must be backed by future in vivo studies and clinical trials before therapeutic guidelines are issued regarding specific antivenom use in a clinical setting.

scholarly journals Basic Conceptual Structure of Evolutionary Ecology

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Rogério Parentoni Martins
Keyword(s):  
Evolutionary Biology ◽  
Evolutionary Ecology ◽  
Genotypic Variation ◽  
Structured Populations ◽  
Phenotypic Variance ◽  
Selective Agents ◽  
Survival And Reproduction ◽  
Environmental Variations ◽  
Successive Generations ◽  
Evolutionary Consequences

Concepts are linguistic structures with specific syntax and semantics used as sources of communicating ideas. Concepts can be simple (e.g., tree), complex (e.g., adaptation) and be part of a network of interactions that characterize an area of scientific research. The conceptual interrelationships and some evolutionary consequences upon which these interrelations are based will be addressed here. The evolutionary ecology is an area of research from the population evolutionary biology that deals mainly with the effect of positive natural selection on panmictic and structured populations. Environmental factors, conditions and variable resources in time and space, constitute the selective agents that act on the phenotypic and genotypic variation of populations in a single generation, could result in evolutionary adaptations, which are simply those traits that are most likely to confer survival and reproduction (evolutionary fitness) of the phenotypes that carry them in successive generations. The bases of adaptation are mainly genetic and transmitted vertically (classical Mendelian mechanisms) or horizontally (in the case of microorganisms). The phenotypic variance of the population is a conjoint consequence of the additive genotypic variance (heritability), nonadditive variance (dominance and epistasis), pleiotropy and the interaction between genotype and environment. The ability of the same genotype to respond to spatial environmental variations can result in phenotypic plasticity that manifests itself through reaction norms. The total phenotypic variation and its genetic and environmental components influence the ability of a population to evolve (evolvability).

Managing visitor experiences in nature-based tourism

2021 ◽  
Keyword(s):  
Empirical Evidence ◽  
Case Studies ◽  
Current Knowledge ◽  
Visitor Experiences ◽  
Tourism Experience ◽  
Tourism Destinations

Abstract This book on visitor experiences in nature-based tourism destinations demonstrates current knowledge using empirical evidence covering six continents. It provides insights into conceptual issues as well as case studies. Content is presented in three main parts: 'Nature-based Experiences in Tourism', 'Managing the Nature-based Tourism Experience' and 'Visitor Experiences and Destination Management'. The book has 16 chapters and a subject index.

Revisiting the question of nucleated versus enucleated erythrocytes in birds and mammals

2021 ◽  
Author(s):  
Kang Nian Yap ◽  
Yufeng Zhang
Keyword(s):  
Evolutionary Biology ◽  
Current Knowledge ◽  
Mammalian Species ◽  
Volume Ratio ◽  
Comparative Approach ◽  
Energetic Cost ◽  
Cell Organelles ◽  
Mean Cell Volume ◽  
Physiological Functions ◽  
Avian Erythrocytes

Erythrocyte enucleation is thought to have evolved in mammals to support their energetic cost of high metabolic activities. However, birds face similar selection pressure yet possess nucleated erythrocytes. Current hypotheses on the mammalian erythrocyte enucleation claim that the absence of cell organelles allows erythrocytes to 1) pack more hemoglobin into the cells to increase oxygen carrying capacity and 2) decrease erythrocyte size for increased surface area-to-volume ratio, and improved ability to traverse small capillaries. In this article, we first empirically tested current hypotheses using both conventional and phylogenetically informed analysis comparing literature values of mean cell hemoglobin concentration (MCHC) and mean cell volume (MCV) between 181 avian and 194 mammalian species. We found no difference in MCHC levels between birds and mammals using both conventional and phylogenetically corrected analysis. MCV was higher in birds than mammals according to conventional analysis, but the difference was lost when we controlled for phylogeny. These results suggested that avian and mammalian erythrocytes may employ different strategies to solve a common problem. To further investigate existing hypotheses or develop new hypothesis, we need to understand the functions of various organelles in avian erythrocytes. Consequently, we covered potential physiological functions of various cell organelles in avian erythrocytes based on current knowledge, while making explicit comparisons to their mammalian counterparts. Finally, we proposed by taking an integrative and comparative approach, using tools from molecular biology to evolutionary biology, would allow us to better understand the fundamental physiological functions of various components of avian and mammalian erythrocytes.

Soil and ecosystem services: Current knowledge and evidences from Italian case studies

2018 ◽  
Vol 123 ◽  
pp. 693-698 ◽  
Author(s):  
Ferrarini Andrea ◽  
Claudio Bini ◽  
Stefano Amaducci
Keyword(s):  
Ecosystem Services ◽  
Case Studies ◽  
Current Knowledge ◽  
Italian Case

Diversity

2017 ◽  
Author(s):  
Alfonso Troisi
Keyword(s):  
Evolutionary Biology ◽  
Current Knowledge ◽  
Emotional Reactions ◽  
Cultural Relativism ◽  
Primate Species ◽  
Stabilizing Selection ◽  
Behavioral Diversity ◽  
Evolutionary Origins ◽  
Living Species ◽  
Intrinsic Feature

From the perspective of evolutionary biology, diversity is an intrinsic feature of any living species and a target on which natural selection can act in opposite ways: either decreasing it (stabilizing selection) or increasing it (diversifying selection). This duality is reflected in our emotional attitude toward diversity. This chapter summarizes current knowledge on the evolutionary origins of emotional reactions to physical and behavioral diversity in human cultures. After a preliminary discussion of “alternative strategies” observed by ethologists in primate species, the chapter explores the biological roots of intolerance, xenophobia, racism, discrimination, and other forms of rejection of diversity. Findings that have linked ethnocentrism to primitive defenses against infectious diseases are reviewed. Subsequently, the chapter describes how a bias toward “normality” has always lived alongside a powerful attraction to diversity. The chapter closes with reflections based on recent psychiatric and anthropological reports that show how the issue of tolerance of cultural diversity is an unsolved problem, in spite of reassuring claims of the advocates of cultural relativism.

Urban Evolutionary Biology

2020 ◽  
Keyword(s):  
Urban Space ◽  
Evolutionary Biology ◽  
Current Knowledge ◽  
Social Characteristics ◽  
Urban Habitat ◽  
Evolutionary Processes ◽  
Urban Neighbourhoods ◽  
Evolutionary Changes ◽  
Research Themes ◽  
New Research

Cities occupy about 3 per cent of the Earth’s habitable land area and are home to one out of two humans worldwide; both estimates are predicted to grow. Urban space is thus becoming an important, novel ecological niche for humans and wildlife alike. Building on knowledge gathered by urban ecologists during the last half century, evidence of evolutionary responses to urbanization has rapidly emerged. Urban evolutionary biology is a nascent yet fast-growing field of research—and a fascinating testing ground for evolutionary biologists worldwide. Urbanization offers a great range of opportunities to examine evolutionary processes because of the radically altered and easily quantifiable urban habitat, and the large number of cities worldwide, enabling rigorous, replicated tests of evolutionary hypotheses. Urban populations are increasingly exhibiting both neutral and adaptive evolutionary changes at levels ranging from genotypes to phenotypes. The novelty of urban evolutionary biology is that these changes are driven by the cities we have built, including effects of infrastructure, pollution, and social characteristics of our urban neighbourhoods. It will thereby enrich the field of evolutionary biology with emergent yet incredibly potent new research themes where the urban habitat is key. In a series of sixteen chapters written by leading evolutionary biologists working on urban drivers of evolution, Urban Evolutionary Biology is the first academic book in the field. It synthesizes current knowledge on evolutionary processes occurring literally on our doorstep, across the globe, and in each city independently.

scholarly journals Avatars Going Mainstream: Typology of Tropes in Avatar-Based Storytelling Practices

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Marta Tymińska
Keyword(s):  
Popular Culture ◽  
Video Games ◽  
Case Studies ◽  
Current Knowledge ◽  
Game Studies ◽  
Shared Experience ◽  
Media Audiences

Due to the growing popularity of video games, gaming itself has become a shared experience among media audiences worldwide. The phenomenon of avatar-based games has led to the emergence of new storytelling practices. The paper proposes a typology of tropes in these avatar-based narratives focusing on non-game case studies. Suggested tropes are also confronted with the latest research on avatars in the area of game studies and current knowledge of the issues concerning the player-avatar relationship. Some of the most popular misconceptions regarding the gameplay experience and its representation in non-game media are exposed as a result of this analysis. The research confirms that popular culture perceives gaming experience as closely related to the player identity, as the latter inspires new genres of non-game narratives.

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