Journal articles: 'Niche processes'

7

Gravel, Dominique, Charles D. Canham, Marilou Beaudet, and Christian Messier. "Reconciling niche and neutrality: the continuum hypothesis." Ecology Letters 9, no. 4 (2006): 399–409. https://doi.org/10.5281/zenodo.13409664.

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(Uploaded by Plazi for the Bat Literature Project) In this study, we ask if instead of being fundamentally opposed, niche and neutral theories could simply be located at the extremes of a continuum. First, we present a model of recruitment probabilities that combines both niche and neutral processes. From this model, we predict and test whether the relative importance of niche vs. neutral processes in controlling community dynamics will vary depending on community species richness, niche overlap and dispersal capabilities of species (both local and long distance). Results demonstrate that niche and neutrality form ends of a continuum from competitive to stochastic exclusion. In the absence of immigration, competitive exclusion tends to create a regular spacing of niches. However, immigration prevents the establishment of a limiting similarity. The equilibrium community consists of a set of complementary and redundant species, with their abundance determined, respectively, by the distribution of environmental conditions and the amount of immigration.

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8

Gravel, Dominique, Charles D. Canham, Marilou Beaudet, and Christian Messier. "Reconciling niche and neutrality: the continuum hypothesis." Ecology Letters 9, no. 4 (2006): 399–409. https://doi.org/10.5281/zenodo.13409664.

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Abstract:

(Uploaded by Plazi for the Bat Literature Project) In this study, we ask if instead of being fundamentally opposed, niche and neutral theories could simply be located at the extremes of a continuum. First, we present a model of recruitment probabilities that combines both niche and neutral processes. From this model, we predict and test whether the relative importance of niche vs. neutral processes in controlling community dynamics will vary depending on community species richness, niche overlap and dispersal capabilities of species (both local and long distance). Results demonstrate that niche and neutrality form ends of a continuum from competitive to stochastic exclusion. In the absence of immigration, competitive exclusion tends to create a regular spacing of niches. However, immigration prevents the establishment of a limiting similarity. The equilibrium community consists of a set of complementary and redundant species, with their abundance determined, respectively, by the distribution of environmental conditions and the amount of immigration.

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9

Gravel, Dominique, Charles D. Canham, Marilou Beaudet, and Christian Messier. "Reconciling niche and neutrality: the continuum hypothesis." Ecology Letters 9, no. 4 (2006): 399–409. https://doi.org/10.5281/zenodo.13409664.

Full text

Abstract:

(Uploaded by Plazi for the Bat Literature Project) In this study, we ask if instead of being fundamentally opposed, niche and neutral theories could simply be located at the extremes of a continuum. First, we present a model of recruitment probabilities that combines both niche and neutral processes. From this model, we predict and test whether the relative importance of niche vs. neutral processes in controlling community dynamics will vary depending on community species richness, niche overlap and dispersal capabilities of species (both local and long distance). Results demonstrate that niche and neutrality form ends of a continuum from competitive to stochastic exclusion. In the absence of immigration, competitive exclusion tends to create a regular spacing of niches. However, immigration prevents the establishment of a limiting similarity. The equilibrium community consists of a set of complementary and redundant species, with their abundance determined, respectively, by the distribution of environmental conditions and the amount of immigration.

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10

Gravel, Dominique, Charles D. Canham, Marilou Beaudet, and Christian Messier. "Reconciling niche and neutrality: the continuum hypothesis." Ecology Letters 9, no. 4 (2006): 399–409. https://doi.org/10.5281/zenodo.13409664.

Full text

Abstract:

(Uploaded by Plazi for the Bat Literature Project) In this study, we ask if instead of being fundamentally opposed, niche and neutral theories could simply be located at the extremes of a continuum. First, we present a model of recruitment probabilities that combines both niche and neutral processes. From this model, we predict and test whether the relative importance of niche vs. neutral processes in controlling community dynamics will vary depending on community species richness, niche overlap and dispersal capabilities of species (both local and long distance). Results demonstrate that niche and neutrality form ends of a continuum from competitive to stochastic exclusion. In the absence of immigration, competitive exclusion tends to create a regular spacing of niches. However, immigration prevents the establishment of a limiting similarity. The equilibrium community consists of a set of complementary and redundant species, with their abundance determined, respectively, by the distribution of environmental conditions and the amount of immigration.

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11

Latombe, Guillaume, Cang Hui, and Melodie A. McGeoch. "Beyond the continuum: a multi-dimensional phase space for neutral–niche community assembly." Proceedings of the Royal Society B: Biological Sciences 282, no. 1821 (2015): 20152417. http://dx.doi.org/10.1098/rspb.2015.2417.

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Neutral and niche processes are generally considered to interact in natural communities along a continuum, exhibiting community patterns bounded by pure neutral and pure niche processes. The continuum concept uses niche separation, an attribute of the community, to test the hypothesis that communities are bounded by pure niche or pure neutral conditions. It does not accommodate interactions via feedback between processes and the environment. By contrast, we introduce the Community Assembly Phase Space (CAPS), a multi-dimensional space that uses community processes (such as dispersal and niche selection) to define the limiting neutral and niche conditions and to test the continuum hypothesis. We compare the outputs of modelled communities in a heterogeneous landscape, assembled by pure neutral, pure niche and composite processes. Differences in patterns under different combinations of processes in CAPS reveal hidden complexity in neutral–niche community dynamics. The neutral–niche continuum only holds for strong dispersal limitation and niche separation. For weaker dispersal limitation and niche separation, neutral and niche processes amplify each other via feedback with the environment. This generates patterns that lie well beyond those predicted by a continuum. Inferences drawn from patterns about community assembly processes can therefore be misguided when based on the continuum perspective. CAPS also demonstrates the complementary information value of different patterns for inferring community processes and captures the complexity of community assembly. It provides a general tool for studying the processes structuring communities and can be applied to address a range of questions in community and metacommunity ecology.

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12

Bar-Massada, Avi. "Complex relationships between species niches and environmental heterogeneity affect species co-occurrence patterns in modelled and real communities." Proceedings of the Royal Society B: Biological Sciences 282, no. 1813 (2015): 20150927. http://dx.doi.org/10.1098/rspb.2015.0927.

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Species co-occurrence analysis is commonly used to assess how interspecific interactions dictate community assembly. Non-random co-occurrences, however, may also emerge from niche differences as well as environmental heterogeneity. The relationships between species co-occurrence patterns, environmental heterogeneity and species niches are not fully understood, due to complex interactions among them. To analyse the relationships among these patterns and processes, I developed synthetic community models and analysed a large dataset of tree species across the conterminous United States. Niche overlap and environmental heterogeneity had significant and contrasting effects on species co-occurrence patterns, in both modelled and real communities. Niche breadth, in turn, affected the effect sizes of both variables on species co-occurrence patterns. The effect of niche breadth on the relationship between co-occurrence and niche overlap was markedly consistent between modelled and real communities, while its effect on the relationship between co-occurrence and environmental heterogeneity was mostly consistent between real and modelled data. The results of this analysis highlight the complex and interactive effects of species niche overlap, niche breadth and environmental heterogeneity on species co-occurrence patterns. Therefore, inferring ecological processes from co-occurrence patterns without accounting for these fundamental characteristics of species and environments may lead to biased conclusions.

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13

Gómez, Camila, Elkin A. Tenorio, Paola Montoya, and Carlos Daniel Cadena. "Niche-tracking migrants and niche-switching residents: evolution of climatic niches in New World warblers (Parulidae)." Proceedings of the Royal Society B: Biological Sciences 283, no. 1824 (2016): 20152458. http://dx.doi.org/10.1098/rspb.2015.2458.

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Differences in life-history traits between tropical and temperate lineages are often attributed to differences in their climatic niche dynamics. For example, the more frequent appearance of migratory behaviour in temperate-breeding species than in species originally breeding in the tropics is believed to have resulted partly from tropical climatic stability and niche conservatism constraining tropical species from shifting their ranges. However, little is known about the patterns and processes underlying climatic niche evolution in migrant and resident animals. We evaluated the evolution of overlap in climatic niches between seasons and its relationship to migratory behaviour in the Parulidae, a family of New World passerine birds. We used ordination methods to measure seasonal niche overlap and niche breadth of 54 resident and 49 migrant species and used phylogenetic comparative methods to assess patterns of climatic niche evolution. We found that despite travelling thousands of kilometres, migrants tracked climatic conditions across the year to a greater extent than tropical residents. Migrant species had wider niches than resident species, although residents as a group occupied a wider climatic space and niches of migrants and residents overlapped extensively. Neither breeding latitude nor migratory distance explained variation among species in climatic niche overlap between seasons. Our findings support the notion that tropical species have narrower niches than temperate-breeders, but does not necessarily constrain their ability to shift or expand their geographical ranges and become migratory. Overall, the tropics may have been historically less likely to experience the suite of components that generate strong selection pressures for the evolution of migratory behaviour.

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14

Yang, Zhiyuan, Jiayi Xu, Junlin Li, et al. "Stochastic Processes Shape Bacterial Community Diversity Patterns along Plant Niche Gradients." Agronomy 14, no. 1 (2024): 204. http://dx.doi.org/10.3390/agronomy14010204.

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The ecological niche gradient is an important determinant of microbial community structure. In this paper, we studied variation in rhizosphere bacterial diversity and community composition along an ecological niche gradient. We used the high-throughput sequencing of 16S rRNA genes to study changes in the rhizosphere soil microbial communities of six grass and four shrub species during the secondary succession of abandoned farmland on the Loess Plateau of China. A structural equation model (SEM) was employed to disentangle the relative contribution of ecological niche and soil properties to bacterial diversity and community composition. Proteobacteria, Acidobacteria, and Actinobacteria were the dominant phyla of rhizosphere bacteria in all samples. During the dynamics of the plant niche from low to high, bacterial community composition transitioned from Actinobacteria + Acidobacteria to Proteobacteria + Bacteroidetes higher abundance. Moreover, the bacterial diversity and species richness changed with an increasing niche gradient, showing a clear differentiation in the rhizosphere bacterial community of grassland and shrubland. Further, diversity and species richness decreased from the middle niche of B. ischaemum to the poles, indicating that the succession process had not yet reached the climax community stage. Community assembly analysis suggested that the stochastic process gradually strengthened along the increasing ecological niche gradient, especially the drift effect. Furthermore, SEM analysis showed that the ecological niche had significant negative effects on soil properties and bacterial richness, while the effects on bacterial diversity and the stochastic processes of community assembly were weakened and insignificant. Altogether, our findings suggest that the complex interaction of the ecological niche with bacterial diversity and composition was determined by soil properties. Further, bacterial diversity was not necessarily higher with increasing ecological niche gradients.

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15

Khilazheva, E. D., A. V. Morgun, E. B. Boytsova, et al. "Features of the in vitro expression profile of hippocampal neurogenic niche cells during optogenetic stimulation." Biomeditsinskaya Khimiya 67, no. 1 (2021): 34–41. http://dx.doi.org/10.18097/pbmc20216701034.

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In the central nervous system of mammals, there are specialized areas in which neurogenesis — neurogenic niches — is observed in the postnatal period. It is believed that astrocytes in the composition of neurogenic niches play a significant role in the regulation of neurogenesis, and therefore they are considered as a promising “target” for the possible control of neurogenesis, including the use of optogenetics. In the framework of this work, we formed an in vitro model of a neurogenic niche, consisting of cerebral endothelial cells, astrocytes and neurospheres. Astrocytes in the neurogenic niche model expressed canalorodopsin ChR2 and underwent photoactivation. The effect of photoactivated astrocytes on the expression profile of neurogenic niche cells was evaluated using immunocytochemical analysis methods. It was found that intact astrocytes in the composition of the neurogenic niche contribute to neuronal differentiation of stem cells, as well as the activation of astroglia expressing photosensitive proteins, changes the expression of molecules characterized by intercellular interactions of pools of resting and proliferating cells in the composition of the neurogenic niche with the participation of NAD+ (Cx43, CD38, CD157), lactate (MCT1). In particular, the registered changes reflect a violation of the paracrine intercellular interactions of two subpopulations of cells, one of which acts as a source of NAD+, and the second as a consumer of NAD+ to ensure the processes of intracellular signal transduction; a change in the mechanisms of lactate transport due to aberrant expression of the lactate transporter MCT1 in cells forming a pool of cells developing along the neuronal path of differentiation. In general, with photostimulation of niche astrocytes, the total proliferative activity increases mainly due to neural progenitor cells, but not neural stem cells. Thus, optogenetic activation of astrocytes can become a promising tool for controlling the activity of neurogenesis processes and the formation of a local proneurogenic microenvironment in an in vitro model of a neurogenic niche.

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Hamlin, Robert, John Knight, and Ron Cuthbert. "Niche marketing and farm diversification processes: Insights from New Zealand and Canada." Renewable Agriculture and Food Systems 31, no. 1 (2015): 86–98. http://dx.doi.org/10.1017/s1742170514000489.

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AbstractIn many developed countries agriculture is undergoing significant changes. Traditional commodity markets are increasingly being supplemented or even displaced by niche markets served by firms producing specialty products. The purpose of this paper is to determine why firms seek out niche markets and what contributes to their success. This paper investigates the characteristics that make niche markets attractive to small and medium-sized agricultural firms and the ways in which these firms become highly adapted for their chosen niche. Results indicate that forming alliances and the development of horizontal and vertical networks are among the most common and most important strategies employed by successful niche marketers. The study found that firms market niche products as part of a portfolio of products that often includes an anchoring commodity. Results also suggest that aggressive growth and pricing strategies may negatively impact a firm's ability to sustain barriers to entry. The development of a niche positioning strategy is often the outcome of a reaction to an existing situation rather than of a priori strategic planning.

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17

Feng, Li, Lipan Zhou, Tianyi Zhang, and Xumei Wang. "Niche Dynamics Below the Species Level: Evidence from Evaluating Niche Shifts within Quercus aquifolioides." Forests 14, no. 4 (2023): 690. http://dx.doi.org/10.3390/f14040690.

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The role of ecological niches in lineage diversification has been the subject of long-standing interest of ecologists and evolutionary biologists. Specific responses to climate change can arise below the species level, resulting in differentiated adaptation or movement patterns within a given species. Thus, the urgent need to model potential responses to ongoing climate changes among genetically distinct populations within a species is increasingly recognized. In this study, we utilize the information of intraspecific variation within Quercus aquifolioides as a priori, and then focus on the potential distribution ranges and niche dynamics of its three intraspecific lineages (WSP, HDM, and Tibet) under current environmental conditions via ecological niche models (ENMs) and PCA-env ordination method, respectively. Our results indicated that the three lineages have occupied differentiated climatic niches. Although the three lineages have distinctly adaptive strategies for homogeneous environmental conditions, some lineages had sympatric projecting areas. The PCA-env demonstrated that the lineage pair WSP vs. HDM had the largest niche overlap while Tibet vs. HDM showed the smallest one. Moreover, the hypothesis of the niche was indistinguishable within the three lineages rejected, indicating the presence of niche divergence rather than niche conservatism below the species level. Our findings highlight the potential of modeling intraspecific responses to climate change and provide insights into lineage diversification within Q. aquifolioides, permitting the exploration of the information determined by niche evaluations and comparisons to understand plant diversification processes below the species level in biodiversity hotspots.

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Pesch, Udo, Anne-Lorène Vernay, Ellen van Bueren, and Sofie Pandis Iverot. "Niche entrepreneurs in urban systems integration: On the role of individuals in niche formation." Environment and Planning A: Economy and Space 49, no. 8 (2017): 1922–42. http://dx.doi.org/10.1177/0308518x17705383.

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In many sustainable urban innovation projects, the efforts, endurance and enthusiasm of individuals at key positions are considered a crucial factor for success. This article studies the role of individual agency in sociotechnical niches by using Kingdon’s agenda-setting model. Although strategic niche management is commonly used to study processes of urban innovation, the process of niche formation and the role of individual agency has been understudied. We will introduce the notion of the ‘niche entrepreneur’ as an actor who, analogous to Kingdon’s policy entrepreneur, connects the elements that are needed to develop a successful niche that allows learning for sustainability transitions. We will study the process of niche formation and the role of individual entrepreneurship therein, and identify the strategies that have been used by individuals to create a successful niche. This will be done for three cases in urban systems integration: the development of Eva Lanxmeer, a residential district in a drinking water retention area in Culemborg, the Netherlands; the transformation of the waste management practices of Lille Métropole Urban Community, France; and the development of the urban district Hammarby Sjöstad, Sweden. Our findings show that for the successful formation of niches, it is necessary to create ambitious, but clear goals and matching concrete operational plans; niche entrepreneurs may play the role of project champions that contribute significantly to the operationalization, monitoring and the effectuation of the original goals of the project; the strategies of niche entrepreneurs emphasize the building of coalitions and the securing of space for learning.

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19

Ma, Eric J., Nichola J. Hill, Justin Zabilansky, Kyle Yuan, and Jonathan A. Runstadler. "Reticulate evolution is favored in influenza niche switching." Proceedings of the National Academy of Sciences 113, no. 19 (2016): 5335–39. http://dx.doi.org/10.1073/pnas.1522921113.

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Reticulate evolution is thought to accelerate the process of evolution beyond simple genetic drift and selection, helping to rapidly generate novel hybrids with combinations of adaptive traits. However, the long-standing dogma that reticulate evolutionary processes are likewise advantageous for switching ecological niches, as in microbial pathogen host switch events, has not been explicitly tested. We use data from the influenza genome sequencing project and a phylogenetic heuristic approach to show that reassortment, a reticulate evolutionary mechanism, predominates over mutational drift in transmission between different host species. Moreover, as host evolutionary distance increases, reassortment is increasingly favored. We conclude that the greater the quantitative difference between ecological niches, the greater the importance of reticulate evolutionary processes in overcoming niche barriers.

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Blanch, Estel, Adrià López-Baucells, Vanessa A. Mata, Carles Flaquer, and David López-Bosch. "To share or not to share: DNA metabarcoding reveals trophic niche overlap between sympatric trawling bats." European Journal of Wildlife Research 69, no. 5 (2023): 90. https://doi.org/10.5281/zenodo.13469941.

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(Uploaded by Plazi for the Bat Literature Project) Understanding ecological niches is essential to comprehend the processes that allow similar species to occur sympatrically. Niche overlap can result in some degree of competition when resources are limited, and therefore, sympatric species must differ to some extent at some niche level in order to co-exist. The two trawling bats that co-occur along the Mediterranean region share their foraging strategy and feeding grounds, potentially consuming similar prey species. However, no research has been conducted to elucidate their dietary niche similarities or differences to test whether these may shape their sympatric foraging occurrence and distribution. We used DNA metabarcoding to study the dietary composition and niche overlap of Myotis capaccinii (an exceptionally endangered species) and M. daubentonii (a relatively common species) during the breeding season in northeastern Iberia. Unlike previous studies, Trichoptera was the most frequently consumed prey order for both bat species, followed by Diptera (mainly Chironomidae). We also report, for the second time, fish consumption by M. capaccinii in the Iberian Peninsula, and provide the fourth report of piscivory for European bats. Although minor differences in diet composition between both trawling bats were found, they presented highly overlapping dietary niches and similar dietary niche breadths, suggesting that they exploit similar trophic resources. Overall, the current results suggest that both species may have found a balance to co-occur in the same foraging niche without interspecific competition being a limiting factor.

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Blanch, Estel, Adrià López-Baucells, Vanessa A. Mata, Carles Flaquer, and David López-Bosch. "To share or not to share: DNA metabarcoding reveals trophic niche overlap between sympatric trawling bats." European Journal of Wildlife Research 69, no. 5 (2023): 90. https://doi.org/10.5281/zenodo.13469941.

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(Uploaded by Plazi for the Bat Literature Project) Understanding ecological niches is essential to comprehend the processes that allow similar species to occur sympatrically. Niche overlap can result in some degree of competition when resources are limited, and therefore, sympatric species must differ to some extent at some niche level in order to co-exist. The two trawling bats that co-occur along the Mediterranean region share their foraging strategy and feeding grounds, potentially consuming similar prey species. However, no research has been conducted to elucidate their dietary niche similarities or differences to test whether these may shape their sympatric foraging occurrence and distribution. We used DNA metabarcoding to study the dietary composition and niche overlap of Myotis capaccinii (an exceptionally endangered species) and M. daubentonii (a relatively common species) during the breeding season in northeastern Iberia. Unlike previous studies, Trichoptera was the most frequently consumed prey order for both bat species, followed by Diptera (mainly Chironomidae). We also report, for the second time, fish consumption by M. capaccinii in the Iberian Peninsula, and provide the fourth report of piscivory for European bats. Although minor differences in diet composition between both trawling bats were found, they presented highly overlapping dietary niches and similar dietary niche breadths, suggesting that they exploit similar trophic resources. Overall, the current results suggest that both species may have found a balance to co-occur in the same foraging niche without interspecific competition being a limiting factor.

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22

Blanch, Estel, Adrià López-Baucells, Vanessa A. Mata, Carles Flaquer, and David López-Bosch. "To share or not to share: DNA metabarcoding reveals trophic niche overlap between sympatric trawling bats." European Journal of Wildlife Research 69, no. 5 (2023): 90. https://doi.org/10.5281/zenodo.13469941.

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Abstract:

(Uploaded by Plazi for the Bat Literature Project) Understanding ecological niches is essential to comprehend the processes that allow similar species to occur sympatrically. Niche overlap can result in some degree of competition when resources are limited, and therefore, sympatric species must differ to some extent at some niche level in order to co-exist. The two trawling bats that co-occur along the Mediterranean region share their foraging strategy and feeding grounds, potentially consuming similar prey species. However, no research has been conducted to elucidate their dietary niche similarities or differences to test whether these may shape their sympatric foraging occurrence and distribution. We used DNA metabarcoding to study the dietary composition and niche overlap of Myotis capaccinii (an exceptionally endangered species) and M. daubentonii (a relatively common species) during the breeding season in northeastern Iberia. Unlike previous studies, Trichoptera was the most frequently consumed prey order for both bat species, followed by Diptera (mainly Chironomidae). We also report, for the second time, fish consumption by M. capaccinii in the Iberian Peninsula, and provide the fourth report of piscivory for European bats. Although minor differences in diet composition between both trawling bats were found, they presented highly overlapping dietary niches and similar dietary niche breadths, suggesting that they exploit similar trophic resources. Overall, the current results suggest that both species may have found a balance to co-occur in the same foraging niche without interspecific competition being a limiting factor.

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23

Blanch, Estel, Adrià López-Baucells, Vanessa A. Mata, Carles Flaquer, and David López-Bosch. "To share or not to share: DNA metabarcoding reveals trophic niche overlap between sympatric trawling bats." European Journal of Wildlife Research 69, no. 5 (2023): 90. https://doi.org/10.5281/zenodo.13469941.

Full text

Abstract:

(Uploaded by Plazi for the Bat Literature Project) Understanding ecological niches is essential to comprehend the processes that allow similar species to occur sympatrically. Niche overlap can result in some degree of competition when resources are limited, and therefore, sympatric species must differ to some extent at some niche level in order to co-exist. The two trawling bats that co-occur along the Mediterranean region share their foraging strategy and feeding grounds, potentially consuming similar prey species. However, no research has been conducted to elucidate their dietary niche similarities or differences to test whether these may shape their sympatric foraging occurrence and distribution. We used DNA metabarcoding to study the dietary composition and niche overlap of Myotis capaccinii (an exceptionally endangered species) and M. daubentonii (a relatively common species) during the breeding season in northeastern Iberia. Unlike previous studies, Trichoptera was the most frequently consumed prey order for both bat species, followed by Diptera (mainly Chironomidae). We also report, for the second time, fish consumption by M. capaccinii in the Iberian Peninsula, and provide the fourth report of piscivory for European bats. Although minor differences in diet composition between both trawling bats were found, they presented highly overlapping dietary niches and similar dietary niche breadths, suggesting that they exploit similar trophic resources. Overall, the current results suggest that both species may have found a balance to co-occur in the same foraging niche without interspecific competition being a limiting factor.

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Liu, Shaodong, Ruihua Liu, Siping Zhang, et al. "The Contributions of Sub-Communities to the Assembly Process and Ecological Mechanisms of Bacterial Communities along the Cotton Soil–Root Continuum Niche Gradient." Microorganisms 12, no. 5 (2024): 869. http://dx.doi.org/10.3390/microorganisms12050869.

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Soil microbes are crucial in shaping the root-associated microbial communities. In this study, we analyzed the effect of the soil–root niche gradient on the diversity, composition, and assembly of the bacterial community and co-occurrence network of two cotton varieties. The results revealed that the bacterial communities in cotton soil–root compartment niches exhibited a skewed species abundance distribution, dominated by abundant taxa showing a strong spatial specificity. The assembly processes of the rhizosphere bacterial communities were mainly driven by stochastic processes, dominated by the enrichment pattern and supplemented by the depletion pattern to recruit bacteria from the bulk soil, resulting in a more stable bacterial community. The assembly processes of the endosphere bacterial communities were determined by processes dominated by the depletion pattern and supplemented by the enrichment pattern to recruit species from the rhizosphere, resulting in a decrease in the stability and complexity of the community co-occurrence network. The compartment niche shaped the diversity of the bacterial communities, and the cotton variety genotype was an important source of diversity in bacterial communities within the compartment niche. We suggest that the moderate taxa contribute to significantly more changes in the diversity of the bacterial community than the rare and abundant taxa during the succession of bacterial communities in the cotton root–soil continuum.

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Scattolini, María Celeste, Andrés Lira-Noriega, Viviana Andrea Confalonieri, Silvia Pietrokovsky, and María Marta Cigliano. "Biogeographical patterns and processes in the genus group Scotussae (Acrididae: Melanoplinae): an integrative approach." Biological Journal of the Linnean Society 131, no. 2 (2020): 417–33. http://dx.doi.org/10.1093/biolinnean/blaa100.

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Abstract A biogeographical study of the genus group Scotussae, a clade of grasshoppers endemic to the subtropical temperate region of the La Plata Basin, South America, was performed within a phylogenetic context to test whether wing reduction reflects evolutionary and ecological processes within the clade. We used an integrative biogeographical approach to determine the role of geohistorical events, geography, ecology and phylogenetic niche conservatism on the distribution and diversification processes of the group. We performed a total evidence phylogenetic analysis and tested the phylogenetic signal of ecological niche traits (niche optimum and niche breadth). We also assessed the degree to which phylogenetic distance is correlated with geographical and ecological niche traits and we used BioGeoBEARS to estimate ancestral ranges. The results provided evidence for phylogenetic niche conservatism as well as a significant association between phylogeny and both geographical and, more strongly, ecological traits. Two main clades were clearly associated with wing development, and evidence points to the evolutionary and ecological processes within these two groups being different. The Brachypterous clade shows evidence that allopatric speciation was the main source of diversification, while for the Macropterous clade sympatric speciation seems more likely.

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Rujing, Yang, Gong Xiang, Hu Xiaokang, Hu Yawen, and Feng Jianmeng. "Global cultivation of wheat crops induces considerable shifts in the range and niche of species relative to their wild progenitors." Environmental Research Communications 3, no. 11 (2021): 115012. http://dx.doi.org/10.1088/2515-7620/ac3906.

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Abstract Species’ range and niche play key roles in understanding ecological and biogeographical patterns, especially in projecting global biotic homogenization and potential distribution patterns of species under global change scenarios. However, few studies have investigated the ability of crop cultivation to influence potential range sizes and niche shifts of species. Wheat and its wild progenitors share the same origin and evolutionary history, and thus provide an excellent system to explore this topic. Using ensembled ecological niche models and niche dynamic models, we studied the potential range sizes of wheat and its wild progenitors, as well as their niche dynamics. Our results showed that wheat had larger range size and niche breadth than its wild progenitors, suggesting that wheat cultivation is a more powerful driver of range and niche expansion than natural niche evolution. Additionally, wheat and its wild progenitors occupied different niche positions, and the former did not conserve the niches inherited from the latter, implying that wheat cultivation considerably induces niche shifts. The niche dynamics between wheat and its wild progenitors were not only closely associated with cultivation but were also modified by the niche conservatism of its wild progenitors. In contrast to most invasive plants, wheat, as a global staple crop species, did not conserve the niche space inherited from its wild progenitors, suggesting that compared with most plant invasions, cultivation may have a stronger effect on niche shifts. Therefore, global niche shifts induced by crop cultivation need much more attention, though the underlying mechanisms require further study.

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Luna-Aranguré, Carlos, and Ella Vázquez-Domínguez. "Bears into the Niche-Space: Phylogeography and Phyloclimatic Model of the Family Ursidae." Diversity 16, no. 4 (2024): 223. http://dx.doi.org/10.3390/d16040223.

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Assessing niche evolution remains an open question and an actively developing area of study. The family Ursidae consists of eight extant species for which, despite being the most studied family of carnivores, little is known about the influence of climate on their evolutionary history and diversification. We evaluated their evolutionary patterns based on a combined phylogeography and niche modeling approach. We used complete mitogenomes, estimated divergence times, generated ecological niche models and applied a phyloclimatic model to determine the species evolutionary and diversification patterns associated with their respective environmental niches. We inferred the family evolutionary path along the environmental conditions of maximum temperature and minimum precipitation, from around 20 million years ago to the present. Our findings show that the phyloclimatic niches of the bear species occupy most of the environmental space available on the planet, except for the most extreme warm conditions, in accordance with the wide geographic distribution of Ursidae. Moreover, some species exhibit broader environmental niches than others, and in some cases, they explore precipitation axes more extensively than temperature axes or vice versa, suggesting that not all species are equally adaptable to these variables. We were able to elucidate potential patterns of niche conservatism and evolution, as well as niche overlapping, suggesting interspecific competitive exclusion between some of the bear species. We present valuable insights into the ecological and evolutionary processes driving the diversification and distribution of the Ursidae. Our approach also provides essential information for guiding effective conservation strategies, particularly in terms of distribution limits in the face of climate change.

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Kemp, René, Johan Schot, and Remco Hoogma. "Regime shifts to sustainability through processes of niche formation: The approach of strategic niche management." Technology Analysis & Strategic Management 10, no. 2 (1998): 175–98. http://dx.doi.org/10.1080/09537329808524310.

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Finn, Jack, Jack Barrie, Elsa João, and Girma Zawdie. "A multilevel perspective of transition to a circular economy with particular reference to a community renewable energy niche." International Journal of Technology Management & Sustainable Development 19, no. 2 (2020): 195–220. http://dx.doi.org/10.1386/tmsd_00022_1.

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This article is an attempt to look into the processes involved in achieving full system transition to a circular economy (CE) through the development of niche activities. Based on a case study relating to a community renewable energy (CRE) niche, the article argues that for transition to take hold and make progress, the socio-technical regimes underpinning the system of a linear economy would need to be disrupted through the agency of niches that bring forth radical innovations across a spectrum of activities. This argument is explored through a case study from the energy sector in Scotland. A Delphi study is conducted to assess the success of the Scottish Government in progressing CRE as a niche aimed at disrupting the incumbent fossil-based energy regime. The study finds that despite the commitment of the Scottish Government to empower, nurture and shield CRE as a niche, there is no clear evidence as yet to show whether these actions have achieved their desired effect of enabling the CRE niche to play a disruptive role. The article also underscores the need for methodological refinement to enhance the robustness of the data used in the evaluation of policy efforts in niche development as a strategy for transition to CE.

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Hernández-Chávez, Iván, Lázaro Guevara, Joaquín Arroyo-Cabrales, and Livia León-Paniagua. "Ecological niche differentiation among Aztec fruit-eating bat subspecies (Chiroptera: Phyllostomidae) in Mesoamerica." Therya 14, no. 1 (2023): 39–47. http://dx.doi.org/10.12933/therya-23-2214.

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Artibeus aztecus is a Mesoamerican montane bat with three currently recognized, allopatric subspecies. No study has evaluated the phylogenetic status of the subspecies. However, through an analysis of its ecological niche and its geographic distribution, here we analyze whether there is differentiation of the climatic requirements for each subspecies, assessing whether niche evolution is a potential factor in subspecies differentiation. We assayed ecological niche models for each subspecies, analyzed the response curves for the most important climatic variables of each model, and generated the potential distribution model for each subspecies. We assayed a background similarity test between the subspecies to determine how similar their niches were. We found differences in climatic requirements for the three allopatric subspecies and the most important variables and their response curves. Potential distribution models concur with Mesoamerican highlands and highlight the lowlands of the isthmus of Tehuantepec and the Nicaraguan depression as possible geographic barriers. Differences found between ecological niches for each subspecies contrast with previous findings for the species and other phyllostomid bats. Niche conservatism may have caused geographic isolation in the past, and differences in environmental requirements may have appeared later. Molecular and morphological analyses are necessary to clarify the taxonomic status of these populations and the evolutionary processes involved in their diversification.

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Guo, Yulun, Tao Wang, García Molinos Jorge, et al. "Differential Responses of Food Web Properties to Opposite Assembly Rules and Species Richness." Water 12, no. 10 (2020): 2828. http://dx.doi.org/10.3390/w12102828.

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Trophic niches condition the energetic performance of species within food webs providing a vital link between food web assembly, species diversity, and functioning of ecosystems. Our understanding of this important link is, however, limited by the lack of empirical tools that can be easily applied to compare entire food webs at regional scales. By comparison, with different a priori synthetic models defined according to specific assembly rules (i.e., purely random, limiting similarity, and niche filtering), we demonstrate that a set of food web properties (trophic richness, evenness, and divergence) are controlled by ecological processes. We further demonstrate that although both limiting similarity and niche filtering are statistically significant assembly processes shaping our studied lake food webs, their relative importance is richness-dependent, and contextual to the specific food web property under consideration. Our results have both important theoretical and practical implications. Theoretically, the observed richness-dependent variation on food web properties contradicts the common criticism on food web theory that food web properties are roughly scale-invariant. Practically, these properties can help avoiding spurious conclusions, while providing useful information for multiple food web niche spaces supporting the ecosystem functioning.

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Weiher, Evan, Deborah Freund, Tyler Bunton, Artur Stefanski, Tali Lee, and Stephen Bentivenga. "Advances, challenges and a developing synthesis of ecological community assembly theory." Philosophical Transactions of the Royal Society B: Biological Sciences 366, no. 1576 (2011): 2403–13. http://dx.doi.org/10.1098/rstb.2011.0056.

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Ecological approaches to community assembly have emphasized the interplay between neutral processes, niche-based environmental filtering and niche-based species sorting in an interactive milieu. Recently, progress has been made in terms of aligning our vocabulary with conceptual advances, assessing how trait-based community functional parameters differ from neutral expectation and assessing how traits vary along environmental gradients. Experiments have confirmed the influence of these processes on assembly and have addressed the role of dispersal in shaping local assemblages. Community phylogenetics has forged common ground between ecologists and biogeographers, but it is not a proxy for trait-based approaches. Community assembly theory is in need of a comparative synthesis that addresses how the relative importance of niche and neutral processes varies among taxa, along environmental gradients, and across scales. Towards that goal, we suggest a set of traits that probably confer increasing community neutrality and regionality and review the influences of stress, disturbance and scale on the importance of niche assembly. We advocate increasing the complexity of experiments in order to assess the relative importance of multiple processes. As an example, we provide evidence that dispersal, niche processes and trait interdependencies have about equal influence on trait-based assembly in an experimental grassland.

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Chan, Charles, Ching-Cheng Chen, Daniel L. Kraft, et al. "Identification and Isolation of the Hematopoietic Stem Cell Niche Initiating Cell Population." Blood 112, no. 11 (2008): 3574. http://dx.doi.org/10.1182/blood.v112.11.3574.3574.

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Abstract Introduction: Identification and understanding of the cells and processes that can generate, sustain and influence the HSC niche and hematopoiesis are critical for the development of a more comprehensive knowledge of normal hematopoiesis, stem cell homing, trafficking, differentiation and hematopoietic pathology. Growth and renewal in many tissues are initiated by stem cells, supported by the microenvironment (niche) in which they reside. While recent work has begun to describe functional interactions between stem cells and their niches, little is known about the formation of stem cell niches. Methods & Results: We established a functional, in vivo assay (via implantation of cells under the renal capsule) to isolate the determinants of hematopoietic stem cell (HSC) niche formation and activity. Using this novel assay, we show that a population of progenitor cells (CD45−Tie2-aV+CD105+Thy1.1−; CD105+Thy1−) sorted from 15.5 dpc fetal limbs and transplanted under the adult mouse renal capsule recruit host-derived vasculatures in a VEGF dependent manner, produce donor-derived ectopic bones through endochondral ossification, and generate a marrow cavity populated by host-derived long term reconstituting HSC (LT-HSC). In contrast, CD45−Tie2-aV+CD105+Thy1a+ (CD105+Thy1+) progenitors form bone that does not contain a marrow cavity. While analyzing these and other sorted populations, we did not observe any instances where niche was present without bone, suggesting that skeletal progenitors are necessary for initiating an HSC niche but osteoblasts alone cannot initiate and support niche activity. Suppression of factors important for HSC maintenance, such as steel factor (SLF), in progenitor populations prior to transplant did not alter their ability to initiate and support an HSC niche. On the other hand, suppression of factors involved in endochondral ossification, such as osterix and VEGF, inhibited niche generation. Furthermore, CD105+Thy1− progenitor populations derived from regions of the fetal mandible or calvaria that do not undergo endochondral ossification form only bone without marrow in our assay. Conclusions: In addition to identifying the limb-derived skeletal progenitor capable of endochondral ossification involved and the basic mechanisms of HSC niche initiation, our study provides a functional framework by which future studies on HSC-niche interactions at the cellular level can be carried out.

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Moskalev, A. A. "Role of stem cell niche in body aging processes." Russian Journal of General Chemistry 80, no. 7 (2010): 1476–81. http://dx.doi.org/10.1134/s1070363210070431.

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Mohandas, Narla, and Joel Anne Chasis. "The erythroid niche: Molecular processes occurring within erythroblastic islands." Transfusion Clinique et Biologique 17, no. 3 (2010): 110–11. http://dx.doi.org/10.1016/j.tracli.2010.05.009.

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Mah, Daphne Ngar-yin, and Darren Man-wai Cheung. "Conceptualizing Niche–Regime Dynamics of Energy Transitions from a Political Economic Perspective: Insights from Community-Led Urban Solar in Seoul." Sustainability 12, no. 12 (2020): 4818. http://dx.doi.org/10.3390/su12124818.

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The complex dynamics between technological niches and regime “lock-in” are critical in determining the pace and outcomes of energy transitions. The socio-technical transitions literature has received growing scholarly attention, but it lacks consideration of the broader political and economic contexts. This paper aims to advance understanding of socio-technical transitions by conceptualizing niche–regime dynamics from a political economic perspective, with reference to a case study of solar in Seoul. Based on in-depth face-to-face interviews with 18 key stakeholders, we have three findings. Firstly, the politico-economic contexts have created an embedded environment in which five factors have a clear influence on niche–regime dynamics. Secondly, the politico-economic contexts created conducive conditions for niche developments on the one hand, but, on the other hand, have created inhibitive conditions that have cancelled out the positive forces and reinforced “lock-in”. Thirdly, the processes occur at multi-scalar levels: Community solar niches in Seoul are conditioned by the broader politico-economic contexts at city and national levels. We conclude that sufficient policy attention should be given to the political economy of a national energy system in order to create conducive conditions for community-led niches to realize the full potential that they could offer in energy transitions.

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Fielding, Claire, and Simón Méndez-Ferrer. "Neuronal regulation of bone marrow stem cell niches." F1000Research 9 (June 16, 2020): 614. http://dx.doi.org/10.12688/f1000research.22554.1.

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The bone marrow (BM) is the primary site of postnatal hematopoiesis and hematopoietic stem cell (HSC) maintenance. The BM HSC niche is an essential microenvironment which evolves and responds to the physiological demands of HSCs. It is responsible for orchestrating the fate of HSCs and tightly regulates the processes that occur in the BM, including self-renewal, quiescence, engraftment, and lineage differentiation. However, the BM HSC niche is disturbed following hematological stress such as hematological malignancies, ionizing radiation, and chemotherapy, causing the cellular composition to alter and remodeling to occur. Consequently, hematopoietic recovery has been the focus of many recent studies and elucidating these mechanisms has great biological and clinical relevance, namely to exploit these mechanisms as a therapeutic treatment for hematopoietic malignancies and improve regeneration following BM injury. The sympathetic nervous system innervates the BM niche and regulates the migration of HSCs in and out of the BM under steady state. However, recent studies have investigated how sympathetic innervation and signaling are dysregulated under stress and the subsequent effect they have on hematopoiesis. Here, we provide an overview of distinct BM niches and how they contribute to HSC regulatory processes with a particular focus on neuronal regulation of HSCs under steady state and stress hematopoiesis.

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Hu, Jintao, Zhaoliang Zheng, Xinyi Wen, et al. "Variation in Niche and Interspecific Associations across Elevations in Subtropical Forest Communities of the Wuyi Mountains, Southeastern China." Forests 15, no. 7 (2024): 1256. http://dx.doi.org/10.3390/f15071256.

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Elucidating changes in the structure and function of plant communities along different elevation ranges will help researchers to analyze the strategies plant communities use in environments and processes influencing niche differentiation. The aims of this paper are to reveal the underlying mechanisms and ecological processes governing the development of subtropical forest ecosystem plant communities. This paper analyzes the forest vegetation of the Wuyi Mountains across the following three elevation ranges: low elevation, mid elevation, and high elevation, spanning from 560 to 2150 m. Twenty and twenty-three dominant tree and shrub layer species, respectively, were identified based on their importance values, and their niches and species associations were further analyzed based on the elevation range. The results showed interspecific associations between tree and shrub species, with the strongest associations observed at mid-elevations. The analysis of niche width and overlap showed that the number of pairs of species with a higher degree of niche overlap decreased with increasing elevation, suggesting that resource use varied at different elevations for both tree and shrub layer species, which may be related to the adaptive capacity of plants at different elevations to the environment and resource use strategies. These findings should contribute to a deeper understanding of the ecological functioning and structural framework of plant communities on Wuyi Mountain.

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Carballo-Morales, Jorge D., Romeo A. Saldaña-Vázquez, Federico Villalobos, and Leonel Herrera-Alsina. "Thermal niche breadth and their relationship with sturnira bat species diversification." Journal of Thermal Biology 117 (June 12, 2023): 103697. https://doi.org/10.5281/zenodo.13477046.

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(Uploaded by Plazi for the Bat Literature Project) The interaction between climatic conditions and the ability of organisms to maintain homeostasis regulates the distribution of species on the planet. However, its influence on macroevolutionary dynamics is not well un derstood. It has been suggested that diversification rates will be different in lineages with narrow thermal niches (specialists) to diversification rates in generalist lineages, but the evidence for this is elusive. Here, we tested this hypothesis by using the most diverse (in species richness and geographic range variation) tropical bat genus within the Phyllostomidae family. We estimated the realized thermal niche breadth of Sturnira species from their geographic range and categorized them as generalists, cold specialists, or warm specialists. We compared dy namic evolutionary models that differ in 1) niche breadth evolution, 2) parental niche breadth inheritance, and 3) whether niche breadth evolution is associated with shifts in diversification rates. Our best-performing model indicates that most Sturnira species arose as specialists in warm climates and that over time, their niche breadth broadens, and just a subset of those species becomes specialists in cold environments. We found that the evo lution of realized thermal niche breadth causes fluctuations in per-lineage rates of diversification, where warm specialists boast the highest speciation rates. However, we found no evidence of these changes in niche neither triggering nor being a result of speciation events themselves; this suggests that diversification events in Sturnira could instead depend on allopatric speciation processes such as the development of geographic barriers.

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Carballo-Morales, Jorge D., Romeo A. Saldaña-Vázquez, Federico Villalobos, and Leonel Herrera-Alsina. "Thermal niche breadth and their relationship with sturnira bat species diversification." Journal of Thermal Biology 117 (June 7, 2023): 103697. https://doi.org/10.5281/zenodo.13477046.

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(Uploaded by Plazi for the Bat Literature Project) The interaction between climatic conditions and the ability of organisms to maintain homeostasis regulates the distribution of species on the planet. However, its influence on macroevolutionary dynamics is not well un derstood. It has been suggested that diversification rates will be different in lineages with narrow thermal niches (specialists) to diversification rates in generalist lineages, but the evidence for this is elusive. Here, we tested this hypothesis by using the most diverse (in species richness and geographic range variation) tropical bat genus within the Phyllostomidae family. We estimated the realized thermal niche breadth of Sturnira species from their geographic range and categorized them as generalists, cold specialists, or warm specialists. We compared dy namic evolutionary models that differ in 1) niche breadth evolution, 2) parental niche breadth inheritance, and 3) whether niche breadth evolution is associated with shifts in diversification rates. Our best-performing model indicates that most Sturnira species arose as specialists in warm climates and that over time, their niche breadth broadens, and just a subset of those species becomes specialists in cold environments. We found that the evo lution of realized thermal niche breadth causes fluctuations in per-lineage rates of diversification, where warm specialists boast the highest speciation rates. However, we found no evidence of these changes in niche neither triggering nor being a result of speciation events themselves; this suggests that diversification events in Sturnira could instead depend on allopatric speciation processes such as the development of geographic barriers.

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Carballo-Morales, Jorge D., Romeo A. Saldaña-Vázquez, Federico Villalobos, and Leonel Herrera-Alsina. "Thermal niche breadth and their relationship with sturnira bat species diversification." Journal of Thermal Biology 117 (July 3, 2023): 103697. https://doi.org/10.5281/zenodo.13477046.

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(Uploaded by Plazi for the Bat Literature Project) The interaction between climatic conditions and the ability of organisms to maintain homeostasis regulates the distribution of species on the planet. However, its influence on macroevolutionary dynamics is not well un derstood. It has been suggested that diversification rates will be different in lineages with narrow thermal niches (specialists) to diversification rates in generalist lineages, but the evidence for this is elusive. Here, we tested this hypothesis by using the most diverse (in species richness and geographic range variation) tropical bat genus within the Phyllostomidae family. We estimated the realized thermal niche breadth of Sturnira species from their geographic range and categorized them as generalists, cold specialists, or warm specialists. We compared dy namic evolutionary models that differ in 1) niche breadth evolution, 2) parental niche breadth inheritance, and 3) whether niche breadth evolution is associated with shifts in diversification rates. Our best-performing model indicates that most Sturnira species arose as specialists in warm climates and that over time, their niche breadth broadens, and just a subset of those species becomes specialists in cold environments. We found that the evo lution of realized thermal niche breadth causes fluctuations in per-lineage rates of diversification, where warm specialists boast the highest speciation rates. However, we found no evidence of these changes in niche neither triggering nor being a result of speciation events themselves; this suggests that diversification events in Sturnira could instead depend on allopatric speciation processes such as the development of geographic barriers.

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Carballo-Morales, Jorge D., Romeo A. Saldaña-Vázquez, Federico Villalobos, and Leonel Herrera-Alsina. "Thermal niche breadth and their relationship with sturnira bat species diversification." Journal of Thermal Biology 117 (July 10, 2023): 103697. https://doi.org/10.5281/zenodo.13477046.

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(Uploaded by Plazi for the Bat Literature Project) The interaction between climatic conditions and the ability of organisms to maintain homeostasis regulates the distribution of species on the planet. However, its influence on macroevolutionary dynamics is not well un derstood. It has been suggested that diversification rates will be different in lineages with narrow thermal niches (specialists) to diversification rates in generalist lineages, but the evidence for this is elusive. Here, we tested this hypothesis by using the most diverse (in species richness and geographic range variation) tropical bat genus within the Phyllostomidae family. We estimated the realized thermal niche breadth of Sturnira species from their geographic range and categorized them as generalists, cold specialists, or warm specialists. We compared dy namic evolutionary models that differ in 1) niche breadth evolution, 2) parental niche breadth inheritance, and 3) whether niche breadth evolution is associated with shifts in diversification rates. Our best-performing model indicates that most Sturnira species arose as specialists in warm climates and that over time, their niche breadth broadens, and just a subset of those species becomes specialists in cold environments. We found that the evo lution of realized thermal niche breadth causes fluctuations in per-lineage rates of diversification, where warm specialists boast the highest speciation rates. However, we found no evidence of these changes in niche neither triggering nor being a result of speciation events themselves; this suggests that diversification events in Sturnira could instead depend on allopatric speciation processes such as the development of geographic barriers.

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Yurova, Kristina A., Olga G. Khaziakhmatova, Elena S. Melashchenko, et al. "Cellular and Molecular Basis of Osteoblastic and Vascular Niches in the Processes of Hematopoiesis and Bone Remodeling (A Short Review of Modern Views)." Current Pharmaceutical Design 25, no. 6 (2019): 663–69. http://dx.doi.org/10.2174/1381612825666190329153626.

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In evolutionary processes, human bone marrow has formed as an organ depot of various types of cells that arise from hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs). Vital HSC activity is controlled through molecular interactions with the niche microenvironment. The review describes current views on the formation of key molecular and cellular components of the HSC niche, which ensure maintenance of home ostasis in stem cell niches, obtained from studies of their role in regulating the proliferation and differentiation of HSCs, including the physiological, reparative and pathological remodeling of bone tissue. Due to rapid developments in biotechnology, tissue bioengineering, and regenerative medicine, information can be useful for developing biomimetic and bioinspired materials and implants that provide an effective bone/bone marrow recovery process after injuries and, to a greater extent, diseases of various etiologies.

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Riede, Felix. "Adaptation and niche construction in human prehistory: a case study from the southern Scandinavian Late Glacial." Philosophical Transactions of the Royal Society B: Biological Sciences 366, no. 1566 (2011): 793–808. http://dx.doi.org/10.1098/rstb.2010.0266.

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The niche construction model postulates that human bio-social evolution is composed of three inheritance domains, genetic, cultural and ecological, linked by feedback selection. This paper argues that many kinds of archaeological data can serve as proxies for human niche construction processes, and presents a method for investigating specific niche construction hypotheses. To illustrate this method, the repeated emergence of specialized reindeer ( Rangifer tarandus ) hunting/herding economies during the Late Palaeolithic ( ca 14.7–11.5 kyr BP) in southern Scandinavia is analysed from a niche construction/triple-inheritance perspective. This economic relationship resulted in the eventual domestication of Rangifer . The hypothesis of whether domestication was achieved as early as the Late Palaeolithic, and whether this required the use of domesticated dogs ( Canis familiaris ) as hunting, herding or transport aids, is tested via a comparative analysis using material culture-based phylogenies and ecological datasets in relation to demographic/genetic proxies. Only weak evidence for sustained niche construction behaviours by prehistoric hunter–gatherer in southern Scandinavia is found, but this study nonetheless provides interesting insights into the likely processes of dog and reindeer domestication, and into processes of adaptation in Late Glacial foragers.

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Omatsu, Yoshiki, and Takashi Nagasawa. "Identification of microenvironmental niches for hematopoietic stem cells and lymphoid progenitors—bone marrow fibroblastic reticular cells with salient features." International Immunology 33, no. 12 (2021): 821–26. http://dx.doi.org/10.1093/intimm/dxab092.

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Abstract Most lineages of blood cells, including immune cells, are generated from hematopoietic stem cells (HSCs) in bone marrow throughout adult life. Since HSCs cannot expand on their own, they require and contact the special microenvironments, termed niches for their maintenance. HSC niches comprise supportive cells that provide adjacent HSCs with critical signals, including cytokines. Although bone marrow microenvironments have been thought to be complex, recent studies have demonstrated that the bone marrow-specific population of fibroblastic reticular cells with long processes, termed CXC chemokine ligand 12 (CXCL12)-abundant reticular (CAR) cells, which overlap strongly with leptin receptor (LepR)-expressing (LepR+) cells, is the major cellular component of niches for HSCs and lymphoid progenitors. CAR cells have salient features, expressing much higher levels of critical HSC niche factors than any other cell populations and function as self-renewing mesenchymal stem cells. Human counterpart of CAR cells is present and affected in diseases, including leukemia. Foxl1+ telocytes recently identified as the niche for intestinal stem cells share some features with CAR cells, suggesting that CAR cells might serve as a prototype for fibroblastic reticular cells creating niche for long-lived cells, including tissue stem cells and memory lymphocytes. These findings provided the basis for future mechanistic studies on the cross-talk between hematopoietic cells and microenvironments in both health and disease.

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Kvam, Gunn-Turid, Trine Magnus, and Egil Petter Stræte. "Product strategies for growth in niche food firms." British Food Journal 116, no. 4 (2014): 723–32. http://dx.doi.org/10.1108/bfj-06-2011-0168.

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Purpose – The aim of this paper is to contribute to a better understanding of growth processes of speciality food firms and how these processes influence the producers' perception of quality demands of the products. Design/methodology/approach – A case study approach was chosen covering four specialty food companies in Norway. This explorative study was conducted from the producer's perspective. Findings – Results show that, as part of growth processes, firms invest in different activities to strengthen the quality of their products to achieve distinctiveness in more competitive markets. The most important quality that contributes to distinctiveness and increased value seems to be traditional handicraft production processes. In some cases, expensive and time-consuming processes are invested in developing qualities that are not transformed into higher value in the market. Research limitations/implications – The number of cases is too small for statistical analysis, but this explorative case study may provide a basis for a survey of a larger sample of firms. Practical implications – The study indicates a need for companies to gain more knowledge about consumers' preferences and behaviour, and to develop product qualities and market communication accordingly. Originality/value – Research is scarce on obstacles to growth in specialty food firms. This study contributes important knowledge to enhance further development of the industry.

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Kaiser, Marie I., Jürgen Gadau, Sylvia Kaiser, Caroline Müller, and S. Helene Richter. "Individualized social niches in animals: Theoretical clarifications and processes of niche change." BioScience, February 7, 2024. http://dx.doi.org/10.1093/biosci/biad122.

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Abstract What are social niches, and how do they arise and change? Our first goal in the present article is to clarify the concept of an individualized social niche and to distinguish it from related concepts, such as a social environment and a social role. We argue that focal individuals are integral parts of individualized social niches and that social interactions with conspecifics are further core elements of social niches. Our second goal in the present article is to characterize three types of processes—social niche construction, conformance, and choice (social NC3 processes)—that explain how individualized social niches originate and change. Our approach brings together studies of behavior, ecology, and evolution and integrates social niches into the broader concept of an individualized ecological niche. We show how clarifying the concept of a social niche and recognizing the differences between the three social NC3 processes enhance and stimulate empirical research.

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Davison, John, Maret Gerz, Inga Hiiesalu, Mari Moora, Marina Semchenko, and Martin Zobel. "Niche types and community assembly." Ecology Letters, October 11, 2023. http://dx.doi.org/10.1111/ele.14327.

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AbstractStudies of niche differentiation and biodiversity often focus on a few niche dimensions due to the methodological challenge of describing hyperdimensional niche space. However, this may limit our understanding of community assembly processes. We used the full spectrum of realized niche types to study arbuscular mycorrhizal fungal communities: distinguishing abiotic and biotic, and condition and resource, axes. Estimates of differentiation in relation to different niche types were only moderately correlated. However, coexisting taxon niches were consistently less differentiated than expected, based on a regional null model, indicating the importance of habitat filtering at that scale. Nonetheless, resource niches were relatively more differentiated than condition niches, which is consistent with the effect of a resource niche‐based coexistence mechanism. Considering niche types, and in particular distinguishing resource and condition niches, provides a more complete understanding of community assembly, compared with studying individual niche axes or the full niche.

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Sharma, Shubhi, Kevin Winner, Jussi Mäkinen, and Walter Jetz. "Measuring the evolution of n‐dimensional environmental niches." Ecography, November 19, 2024. http://dx.doi.org/10.1111/ecog.07285.

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The study of species' environmental niches underpins numerous questions in ecology and evolution and has increasing relevance in a rapidly changing world. Environmental niches, characterized by observations of organisms, inform about a species' specialization in multivariate environment space and help assess their exposure and sensitivity to changing conditions. Environmental niches are also the central concept behind species distribution models (SDMs), which quantify and predict the geographic variation in environmental suitability. Despite the clear role of past evolutionary processes in shaping contemporary biodiversity distribution, the assessment of multivariate or n‐dimensional (where n is the number of environmental axes) niches in a phylogenetic framework has remained limited and constrained by restrictive assumptions. This hampers important existing and emerging applications, such as assessments of niche conservatism, estimates of species' adaptive potential under changing climates, and prediction of niches in less‐studied parts of the tree of life. Here, we introduce a framework that extends SDMs to estimate n‐dimensional environmental niches jointly with underlying evolutionary processes. Specifically, we fit the relationship between niche similarity and phylogenetic distance as a latent Gaussian process across all species in a clade. We demonstrate mathematically how the parameters of the Gaussian process can be linked to existing traditional evolutionary models. Simulations indicate that the approach successfully recovers niche and evolutionary parameters. Applied to two clades of hummingbirds, the presented joint framework uncovers the relationships among species' niches in phylogenetic space and supports the quantification and hypothesis testing of niche evolution. A key advantage of the presented framework is its joint estimation of the evolutionary process alongside niches directly from species observations with uncertainty propagated to evolutionary model parameters. The proposed approach has the potential to increase the robustness of inference about niche evolution and improve understanding of how the processes of niche formation and evolution interact.

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Trappes, Rose, and Sabina Leonelli. "Conceptualising research environments using biological niche concepts." European Journal for Philosophy of Science 15, no. 1 (2025). https://doi.org/10.1007/s13194-025-00640-w.

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Abstract Several philosophers of science have taken inspiration from biological research on niches to conceptualise scientific practice. We systematise and extend three niche-based theories of scientific practice: conceptual ecology, cognitive niche construction, and scientific niche construction. We argue that research niches are a promising conceptual tool for understanding complex and dynamic research environments, which helps to investigate relevant forms of agency and material and social interdependencies, while also highlighting their historical and dynamic nature. To illustrate this, we develop a six-point framework for conceptualising research niches. Within this framework, research niches incorporate multiple and heterogenous material, social and conceptual factors (multi-dimensionality); research outputs arise, persist and differentiate through interactions between researchers and research niches (processes); researchers actively respond to and construct research niches (agency); research niches enable certain interactions and processes and not others (capability); and research niches are defined in relation to particular entities, such as individual researchers, disciplines, or concepts (relationality), and in relation to goals, such as understanding, solving problems, intervention, or the persistence of concepts or instruments (normativity).

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Journal articles on the topic 'Niche processes'

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