scholarly journals Within outlying mean indexes: refining the OMI analysis for the realized niche decomposition

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3364 ◽  
Author(s):  
Stéphane Karasiewicz ◽  
Sylvain Dolédec ◽  
Sébastien Lefebvre

The ecological niche concept has regained interest under environmental change (e.g., climate change, eutrophication, and habitat destruction), especially to study the impacts on niche shift and conservatism. Here, we propose the within outlying mean indexes (WitOMI), which refine the outlying mean index (OMI) analysis by using its properties in combination with theK-select analysis species marginality decomposition. The purpose is to decompose the ecological niche into subniches associated with the experimental design, i.e., taking into account temporal and/or spatial subsets. WitOMI emphasize the habitat conditions that contribute (1) to the definition of species’ niches using all available conditions and, at the same time, (2) to the delineation of species’ subniches according to given subsets of dates or sites. The latter aspect allows addressing niche dynamics by highlighting the influence of atypical habitat conditions on species at a given time and/or space. Then, (3) the biological constraint exerted on the species subniche becomes observable within Euclidean space as the difference between the existing fundamental subniche and the realized subniche. We illustrate the decomposition of published OMI analyses, using spatial and temporal examples. The species assemblage’s subniches are comparable to the same environmental gradient, producing a more accurate and precise description of the assemblage niche distribution under environmental change. The WitOMI calculations are available in the open-access R package “subniche.”

2017 ◽  
Author(s):  
Stéphane Karasiewicz ◽  
Sylvain Dolédec ◽  
Sébastien Lefebvre

The ecological niche concept has a revival interest under climate change, especially to study its impact on niche shift and/or conservatism. Here, we propose the Within Outlying Mean Indexes (WitOMI), which refines the Outlying Mean Index (OMI) analysis by using its properties in combination with the K-select analysis species marginality decomposition. The purpose is to decompose the ecological niche, into subniches associated to the experimental design, i.e. taking into account temporal or spatial subsets. WitOMI emphasizes the habitat conditions that contribute 1) to the definition of species’ niches using all available conditions and, at the same time, 2) to the delineation of species’ subniches according to given subsets of dates or sites. This latter aspect allows addressing niche dynamics by highlighting the influence of atypical habitat conditions on species at a given time or space. 3) Then, the biological constraint exerted on the species subniche becomes observable within the Euclidean space as the difference between the potential subniche and the realized subniche. We illustrate the decomposition of published OMI analysis, using spatial and temporal examples. The species assemblage’s subniches are comparable to the same environmental gradient, producing a more accurate and precise description of the assemblage niche distribution under climate change.


2017 ◽  
Author(s):  
Stéphane Karasiewicz ◽  
Sylvain Dolédec ◽  
Sébastien Lefebvre

The ecological niche concept has a revival interest under climate change, especially to study its impact on niche shift and/or conservatism. Here, we propose the Within Outlying Mean Indexes (WitOMI), which refines the Outlying Mean Index (OMI) analysis by using its properties in combination with the K-select analysis species marginality decomposition. The purpose is to decompose the ecological niche, into subniches associated to the experimental design, i.e. taking into account temporal or spatial subsets. WitOMI emphasizes the habitat conditions that contribute 1) to the definition of species’ niches using all available conditions and, at the same time, 2) to the delineation of species’ subniches according to given subsets of dates or sites. This latter aspect allows addressing niche dynamics by highlighting the influence of atypical habitat conditions on species at a given time or space. 3) Then, the biological constraint exerted on the species subniche becomes observable within the Euclidean space as the difference between the potential subniche and the realized subniche. We illustrate the decomposition of published OMI analysis, using spatial and temporal examples. The species assemblage’s subniches are comparable to the same environmental gradient, producing a more accurate and precise description of the assemblage niche distribution under climate change.


2021 ◽  
Vol 36 (3) ◽  
Author(s):  
Rose Trappes

AbstractNiche construction theory (NCT) aims to transform and unite evolutionary biology and ecology. Much of the debate about NCT has focused on construction. Less attention has been accorded to the niche: what is it, exactly, that organisms are constructing? In this paper I compare and contrast the definition of the niche used in NCT with ecological niche definitions. NCT’s concept of the evolutionary niche is defined as the sum of selection pressures affecting a population. So defined, the evolutionary niche is narrower than the ecological niche. Moreover, when contrasted with a more restricted ecological niche concept, it has a slightly different extension. I point out three kinds of cases in which the evolutionary niche does not coincide with realized ecological niches: extreme habitat degradation, commensalism, and non-limiting or super-abundant resources. These conceptual differences affect the role of NCT in unifying ecology and evolutionary biology.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
William E. Banks ◽  
Marie-Hélène Moncel ◽  
Jean-Paul Raynal ◽  
Marlon E. Cobos ◽  
Daniel Romero-Alvarez ◽  
...  

AbstractMiddle Paleolithic Neanderthal populations occupied Eurasia for at least 250,000 years prior to the arrival of anatomically modern humans. While a considerable body of archaeological research has focused on Neanderthal material culture and subsistence strategies, little attention has been paid to the relationship between regionally specific cultural trajectories and their associated existing fundamental ecological niches, nor to how the latter varied across periods of climatic variability. We examine the Middle Paleolithic archaeological record of a naturally constrained region of Western Europe between 82,000 and 60,000 years ago using ecological niche modeling methods. Evaluations of ecological niche estimations, in both geographic and environmental dimensions, indicate that 70,000 years ago the range of suitable habitats exploited by these Neanderthal populations contracted and shifted. These ecological niche dynamics are the result of groups continuing to occupy habitual territories that were characterized by new environmental conditions during Marine Isotope Stage 4. The development of original cultural adaptations permitted this territorial stability.


2019 ◽  
Author(s):  
Daniele Da Re ◽  
Angel P. Olivares ◽  
William Smith ◽  
Mario Vallejo-Marín

AbstractBackgroundThe ecological niche occupied by novel hybrids can influence their establishment as well as the potential to coexist with their parents. Hybridisation generates new phenotypic combinations, which, in some cases, may allow them to occupy ecological niches outside the environmental envelope of parental taxa. In other cases, hybrids may retain similar ecological niches to their parents, resulting in competition and affecting their coexistence. To date, few studies have quantitatively assessed niche shifts associated with hybridisation in recently introduced populations while simultaneously characterising the niche of parental species in both native and introduced ranges.AimsIn this study, we compared the ecological niche of a novel hybrid plant with the niches of its two parental taxa in the non-native geographic range. We also characterised and compared the parental taxa’s ecological niche of native and introduced populations in order to assess potential niche changes during the invasion process independent of hybridisation.MethodsWe studied monkeyflowers (Mimulus spp., Phrymaceae) that were introduced from the Americas to Europe and New Zealand in the last 200 years. We focused on a novel hybrid, triploid, asexual taxon (M. × robertsii) that occurs only in the British Isles where its two parents (M. guttatus and M. luteus) come into secondary contact. We assembled more than 12,000 geo-referenced occurrence records and eight environmental variables of the three taxa across native and introduced ranges, and conducted ecological niche model analysis using maximum entropy, principal component and niche dynamics analysis.ResultsWe found no evidence of niche shift in the hybrid, M. × robertsii compared to introduced populations of both of their parental taxa. The hybrid had a niche more similar to M. luteus, which is also the rarest of the parental taxa on the introduced range. Among parental monkeyflowers, M. guttatus showed niche conservatism in introduced populations in Europe, but a niche shift in New Zealand, while M. luteus showed a niche shift in Europe. However, the evidence of niche shift should be treated with caution due to the occurence of non-analog climatic conditions, small population size and unfilling niche dynamics.ConclusionsOur results suggest that hybridisation in non-native monkyeflowers did not result in a shift in ecological niche. This niche conservation could create competition between parental and derived taxa, the outcome of which will depend on relative competitive abilities. Further work is needed to establish if the expansion of the hybrid in the introduced range is causally related to the apparent rarity of one of the parents (M.luteus). Finally, the comparison of native and non-native populations of parental taxa, suggest that whether invasions result in niche shifts or not depends on both taxon and geographic region, highlighting the idiosyncratic nature of biological invasions.


2017 ◽  
Vol 3 (1) ◽  
pp. 42-54 ◽  
Author(s):  
Rogério Parentoni Martins

AbstractEcology as a field produces philosophical anxiety, largely because it differs in scientific structure from classical physics. The hypothetical deductive models of classical physics are simple and predictive; general ecological models are predictably limited, as they refer to complex, multi-causal processes. Inattention to the conceptual structure of ecology usually imposes difficulties for the application of ecological models. Imprecise descriptions of ecological niche have obstructed the development of collective definitions, causing confusion in the literature and complicating communication between theoretical ecologists, conservationists and decision and policy-makers. Intense, unprecedented erosion of biodiversity is typical of the Anthropocene, and knowledge of ecology may provide solutions to lessen the intensification of species losses. Concerned philosophers and ecologists have characterised ecological niche theory as less useful in practice; however, some theorists maintain that is has relevant applications for conservation. Species niche modelling, for instance, has gained traction in the literature; however, there are few examples of its successful application. Philosophical analysis of the structure, precision and constraints upon the definition of a ‘niche’ may minimise the anxiety surrounding ecology, potentially facilitating communication between policy-makers and scientists within the various ecological subcultures. The results may enhance the success of conservation applications at both small and large scales.


Author(s):  
A. Townsend Peterson ◽  
Jorge Soberón ◽  
Richard G. Pearson ◽  
Robert P. Anderson ◽  
Enrique Martínez-Meyer ◽  
...  

This chapter proposes a formal and operational definition of a particular niche concept, introduces approaches for characterizing and measuring it, and uses it as a conceptual and terminological basis for describing and understanding much of the related practices of ecological niche modeling and species distribution modeling. It begins with a discussion of the themes that are most important in understanding niche concepts, focusing on three interrelated points: the meaning of “exist indefinitely”; what kinds of variables constitute the hypervolume; and the nature of feedback loops between a species and the variables composing the hypervolume. The chapter then considers the Grinnellian and Eltonian niches as well as the practicalities of estimating Grinnellian niches. It also considers two important interpretations of the niche concept, one of which is concerned with geographic and environmental spaces, and the other emphasizes the Eltonian niche.


Author(s):  
Galen Strawson

This chapter examines the difference between John Locke's definition of a person [P], considered as a kind of thing, and his definition of a subject of experience of a certain sophisticated sort [S]. It first discusses the equation [P] = [S], where [S] is assumed to be a continuing thing that is able to survive radical change of substantial realization, as well as Locke's position about consciousness in relation to [P]'s identity or existence over time as [S]. It argues that Locke is not guilty of circularity because he is not proposing consciousness as the determinant of [S]'s identity over time, but only of [S]'s moral and legal responsibility over time. Finally, it suggests that the terms “Person” and “Personal identity” pull apart, in Locke's scheme of things, but in a perfectly coherent way.


2019 ◽  
Vol 3 ◽  
pp. 00013
Author(s):  
Danny Susanto

<p class="Abstract">The purpose of this study is to analyze the phenomenon known as&nbsp;<span style="font-size: 1rem;">“anglicism”: a loan made to the English language by another language.&nbsp;</span><span style="font-size: 1rem;">Anglicism arose either from the adoption of an English word as a&nbsp;</span><span style="font-size: 1rem;">result of a translation defect despite the existence of an equivalent&nbsp;</span><span style="font-size: 1rem;">term in the language of the speaker, or from a wrong translation, as a&nbsp;</span><span style="font-size: 1rem;">word-by-word translation. Said phenomenon is very common&nbsp;</span><span style="font-size: 1rem;">nowadays and most languages of the world including making use of&nbsp;</span><span style="font-size: 1rem;">some linguistic concepts such as anglicism, neologism, syntax,&nbsp;</span><span style="font-size: 1rem;">morphology etc, this article addresses various aspects related to&nbsp;</span><span style="font-size: 1rem;">Anglicisms in French through a bibliographic study: the definition of&nbsp;</span><span style="font-size: 1rem;">Anglicism, the origin of Anglicisms in French and the current situation,&nbsp;</span><span style="font-size: 1rem;">the areas most affected by Anglicism, the different categories of&nbsp;</span><span style="font-size: 1rem;">Anglicism, the difference between French Anglicism in France and&nbsp;</span><span style="font-size: 1rem;">French-speaking Canada, the attitude of French-speaking society&nbsp;</span><span style="font-size: 1rem;">towards to the Anglicisms and their efforts to stop this phenomenon.&nbsp;</span><span style="font-size: 1rem;">The study shows that the areas affected are, among others, trade,&nbsp;</span><span style="font-size: 1rem;">travel, parliamentary and judicial institutions, sports, rail, industrial&nbsp;</span><span style="font-size: 1rem;">production and most recently film, industrial production, sport, oil industry, information technology,&nbsp;</span><span style="font-size: 1rem;">science and technology. Various initiatives have been implemented either by public institutions or by&nbsp;</span><span style="font-size: 1rem;">individuals who share concerns about the increasingly felt threat of the omnipresence of Anglicism in&nbsp;</span><span style="font-size: 1rem;">everyday life.</span></p>


2018 ◽  
Vol 6 (4) ◽  
pp. 401-428
Author(s):  
Miriam R. Lowi

Studies of identity and belonging in Gulf monarchies tend to privilege tribal or religious affiliation, if not the protective role of the ruler as paterfamilias. I focus instead on the ubiquitous foreigner and explore ways in which s/he contributes to the definition of national community in contemporary gcc states. Building upon and moving beyond the scholarly literature on imported labor in the Gulf, I suggest that the different ‘categories’ of foreigners impact identity and the consolidation of a community of privilege, in keeping with the national project of ruling families. Furthermore, I argue that the ‘European,’ the non-gcc Arab, and the predominantly Asian (and increasingly African) laborer play similar, but also distinct roles in the delineation of national community: while they are differentially incorporated in ways that protect the ‘nation’ and appease the citizen-subject, varying degrees of marginality reflect Gulf society’s perceptions or aspirations of the difference between itself and ‘the other(s).’


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