Community Structure

2016 ◽  
Author(s):  
Andrew P. Hendry
Keyword(s):  
Genetic Diversity ◽  
Community Structure ◽  
Empirical Work ◽  
Community Change ◽  
Phenotypic Change ◽  
Predator Prey ◽  
Current State ◽  
Intraspecific Genetic Diversity ◽  
Community Theory ◽  
Interspecific Diversity

This chapter begins with an outline of mathematical approaches for evaluating how genotypes/phenotypes might alter community structure, which points to predictions about when such effects should be strongest in nature. It then summarizes common approaches for empirical work, which might be broadly classed as (1) the effects of genotypes/phenotypes within and among populations, and (2) the year-by-year correspondence between phenotypic change and community change. These key questions examine the current state of knowledge for two classic applications of evolutionary thinking to community theory: predator–prey interactions and competition. The chapter also considers the importance of intraspecific genetic diversity for community structure, which echoes and extends the intense interest surrounding the effects of interspecific diversity.

scholarly journals Small population size and low genomic diversity have no effect on fitness in experimental translocations of a wild fish

2019 ◽  
Vol 286 (1916) ◽  
pp. 20191989 ◽  
Author(s):  
M. C. Yates ◽  
E. Bowles ◽  
D. J. Fraser
Keyword(s):  
Genetic Diversity ◽  
Body Size ◽  
Population Size ◽  
Brook Trout ◽  
Habitat Degradation ◽  
Species Conservation ◽  
Empirical Work ◽  
Genomic Diversity ◽  
Effective Population ◽  
Isolated Populations

Little empirical work in nature has quantified how wild populations with varying effective population sizes and genetic diversity perform when exposed to a gradient of ecologically important environmental conditions. To achieve this, juvenile brook trout from 12 isolated populations or closed metapopulations that differ substantially in population size and genetic diversity were transplanted to previously fishless ponds spanning a wide gradient of ecologically important variables. We evaluated the effect of genome-wide variation, effective population size ( N e ), pond habitat, and initial body size on two fitness correlates (survival and growth). Genetic variables had no effect on either fitness correlate, which was determined primarily by habitat (pond temperature, depth, and pH) and initial body size. These results suggest that some vertebrate populations with low genomic diversity, low N e , and long-term isolation can represent important sources of variation and are capable of maintaining fitness in, and ultimately persisting and adapting to, changing environments. Our results also reinforce the paramount importance of improving available habitat and slowing habitat degradation for species conservation.

scholarly journals Keeping a cool head at all times. What determines choice consistency?

2020 ◽  
Author(s):  
Felix Jan Nitsch ◽  
Tobias Kalenscher
Keyword(s):  
Empirical Work ◽  
Neurological Status ◽  
Decision Makers ◽  
Expected Returns ◽  
Current State ◽  
Subjective Value ◽  
Choice Consistency ◽  
Blood Alcohol Levels ◽  
Rational Choice Theories ◽  
Trait Factors

Many rational choice theories posit that rational decision makers assign subjective values to all available choice options and choose the option with highest subjective value. Choice options are usually composed of multiple attributes, e.g. healthiness and taste in dietary choice or risk and expected returns in financial choice. These attributes have to be integrated into a single subjective value. Subjective value maximizing choice requires choice consistency, i.e. consistent weighing of the choice attributes across choices. However, empirical work suggests that perfect choice consistency is often violated, for example when decision makers weigh choice attributes differently across multiple decisions. Some researchers propose to extend certain bounds of rationality or to abandon the concept of rationality as adherence to consistency principles altogether. A more conservative stance assumes that perfect consistency can be violated by decision makers in practice, but that consistency principles still can explain large parts of behavior. In a review of the recent literature, we identify factors for compromised consistency relative to baseline conditions. Broadly, we distinguish between undynamic trait factors and fluid state factors. We find evidence for an influence of age, education, intelligence, and neurological status. In contrast, choice consistency appears to be relatively robust to the influence of sex, personality traits, cognitive load, sleepiness and blood alcohol levels. We conclude, that, according to the current state of the literature, only fundamental differences in decision makers, that is, trait differences, have a significant impact on choice consistency.

Stage-structured cycles promote genetic diversity in a predator–prey system of Daphnia and algae

Nature ◽  
2005 ◽  
Vol 433 (7024) ◽  
pp. 413-417 ◽  
Author(s):  
William A. Nelson ◽  
Edward McCauley ◽  
Frederick J. Wrona
Keyword(s):  
Genetic Diversity ◽  
Predator Prey ◽  
Prey System

Brain, Beauty, and Art

2021 ◽  
Keyword(s):  
Empirical Work ◽  
Creative Arts ◽  
Dance Music ◽  
Short History ◽  
Future Directions ◽  
Current State ◽  
History Of ◽  
Music And Architecture ◽  
Volume Targets ◽  
Near Future

Neuroscience joins the long history of discussions about aesthetics in psychology, philosophy, art history, and the creative arts. In this volume, leading scholars in this nascent field reflect on the promise of neuroaesthetics to enrich our understanding of this universal yet diverse facet of human experience. The volume will inform and stimulate anyone with an abiding interest in why it is that, across time and culture, we respond to beauty, engage with art, and are affected by music and architecture. The volume consists of essays from foundational researchers whose empirical work launched the field. Each essay is anchored to an original, peer-reviewed paper from the short history of this new and burgeoning subdiscipline of cognitive neuroscience. Authors of each essay were asked three questions: (1) What motivated the original paper? (2) What were the main findings or theoretical claims made?, and (3) How do those findings or claims fit with the current state and anticipated near future of neuroaesthetics? Together, these essays establish the territory and current boundaries of neuroaesthetics and identify its most promising future directions. Topics include models of neuroaesthetics and discussions of beauty, art, dance, music, literature, and architecture. The volume targets the general public; it also serves as an important resource for scientists, humanitarians, educators, and newcomers to the field, and it will catalyze interdisciplinary conversations critical to the maturation of this young field.

scholarly journals Paleogene community change among terrestrial vertebrates of the Western Hemisphere

1992 ◽  
Vol 6 ◽  
pp. 282-282
Author(s):  
Richard K. Stucky
Keyword(s):  
North America ◽  
South America ◽  
Community Change ◽  
Taxonomic Composition ◽  
Western Hemisphere ◽  
Dental Morphology ◽  
Predator Prey ◽  
Terrestrial Vertebrates ◽  
Morphological Adaptations ◽  
Dinosaur Extinction

Paleogene vertebrate communities in North and South America show dramatic changes in taxonomic composition and ecological organization. Worldwide, mammals diversified substantially following dinosaur extinction (Fig. 1). Most families of living vertebrates appear by the end of the Paleogene. In North America, placental omnivores, herbivores and carnivores dominate mammalian communities, but in South America marsupial carnivores and omnivores and placental herbivores dominate them. Immigration from Asia and Europe to North America of taxa from several placental orders (Perissodactyla, Primates, Artiodactyla, Rodentia, Carnivora, Mesonychia, Creodonta) occurred periodically during the Paleogene. South America, however, was completely isolated from the Paleocene to the Oligocene when Rodentia and perhaps Primates first appear. Despite the independent evolutionary histories of these continents, their constituent species show remarkable convergences in morphological adaptations including body size distributions, dental morphology, and other features. Low resolution chronostratigraphic data for the Paleogene of South America precludes correlation with North American faunas. In North America, patterns of diversification and extinction appear to be related to climatic events. Morphological convergences appear to be related to climate and concomitant habitat change, but may also be a function of coevolution via predator-prey interactions and diffuse competition among guild members.

First fecundity observations on female copepods from three northern Patagonian lakes (Pellaifa, Calafquén, Panguipulli; Chile)

Crustaceana ◽  
2019 ◽  
Vol 92 (8) ◽  
pp. 897-905
Author(s):  
Patricio De los Ríos ◽  
Jorge Farias-Avendaño ◽  
Maria J. Suazo
Keyword(s):  
Community Structure ◽  
Interspecific Competition ◽  
Crustacean Zooplankton ◽  
Calanoid Copepods ◽  
Predator Prey ◽  
Total Length ◽  
Patagonian Lakes ◽  
Egg Number

Abstract The crustacean zooplankton in Chilean Patagonian lakes is characterized by a marked dominance of calanoid copepods when under an oligotrophic status. The aim of the present study was to analyse the number of eggs and the relation of that feature with the total length of females of calanoid and cyclopoid copepods reported in three northern Chilean Patagonian lakes. The calanoid copepods found were Boeckella gracilipes in Lake Pellaifa and Tumeodiaptomus diabolicus in the lakes Panguipulli and Calafquén, whereas the cyclopoid Mesocyclops araucanus was found in the lakes Pellaifa and Calafquén. For calanoid copepods, high egg numbers were found and thus also a high value for the ratio of egg number per female length in Lake Panguipulli, whereas for M. araucanus a high value was found in Lake Pellaifa. These differences would presumably be associated with community structure, specifically predator-prey relationships and possibly other interactions, as, e.g., potential interspecific competition.

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