33 results on '"evolutionary pathways"'
Search Results
2. Exploring Evolutionary Pathways and Abiotic Stress Responses through Genome-Wide Identification and Analysis of the Alternative Oxidase (AOX) Gene Family in Common Oat (Avena sativa).
- Author
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Liu, Boyang, Zhang, Zecheng, Peng, Jinghan, Mou, Haipeng, Wang, Zhaoting, Dao, Yixin, Liu, Tianqi, Kong, Dandan, Liu, Siyu, Xiong, Yanli, Xiong, Yi, Zhao, Junming, Dong, Zhixiao, Chen, Youjun, and Ma, Xiao
- Subjects
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GENE families , *WHEAT , *RICE , *POTENTIAL functions , *ABIOTIC stress , *BRACHYPODIUM - Abstract
The alternative oxidase (AOX), a common terminal oxidase in the electron transfer chain (ETC) of plants, plays a crucial role in stress resilience and plant growth and development. Oat (Avena sativa), an important crop with high nutritional value, has not been comprehensively studied regarding the AsAOX gene family. Therefore, this study explored the responses and potential functions of the AsAOX gene family to various abiotic stresses and their potential evolutionary pathways. Additionally, we conducted a genome-wide analysis to explore the evolutionary conservation and divergence of AOX gene families among three Avena species (Avena sativa, Avena insularis, Avena longiglumis) and four Poaceae species (Avena sativa, Oryza sativa, Triticum aestivum, and Brachypodium distachyon). We identified 12 AsAOX, 9 AiAOX, and 4 AlAOX gene family members. Phylogenetic, motif, domain, gene structure, and selective pressure analyses revealed that most AsAOXs, AiAOXs, and AlAOXs are evolutionarily conserved. We also identified 16 AsAOX segmental duplication pairs, suggesting that segmental duplication may have contributed to the expansion of the AsAOX gene family, potentially preserving these genes through subfunctionalization. Chromosome polyploidization, gene structural variations, and gene fragment recombination likely contributed to the evolution and expansion of the AsAOX gene family as well. Additionally, we hypothesize that AsAOX2 may have potential function in resisting wounding and heat stresses, while AsAOX4 could be specifically involved in mitigating wounding stress. AsAOX11 might contribute to resistance against chromium and waterlogging stresses. AsAOX8 may have potential fuction in mitigating ABA-mediated stress. AsAOX12 and AsAOX5 are most likely to have potential function in mitigating salt and drought stresses, respectively. This study elucidates the potential evolutionary pathways of the AsAOXs gene family, explores their responses and potential functions to various abiotic stresses, identifies potential candidate genes for future functional studies, and facilitates molecular breeding applications in A. sativa. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Phylo-geo haplotype network-based characterization of SARS-CoV-2 strains circulating in India (2020-2022).
- Author
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Potdar, Varsha Atul, Laxmivandana, Rongala, Walimbe, Atul M., Jadhav, Santosh kumar, Pawar, Pratiksha, Kaledhonkar, Aditi, Gupta, Nivedita, Kaur, Harmanmeet, Narayan, Jitendra, Yadav, Pragya D., Abraham, Priya, and Cherian, Sarah
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SARS-CoV-2 , *HAPLOTYPES , *POPULATION genetics , *GENETIC distance - Abstract
Background & objectives Genetic analysis of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) strains circulating in India during 2020-2022 was carried out to understand the evolution of potentially expanding and divergent clades. Methods SARS-CoV-2 sequences (n=612) randomly selected from among the sequences of samples collected through a nationwide network of Virus Research Diagnostic Laboratories during 2020 (n=1532) and Indian sequences available in Global Initiative on Sharing All Influenza Data during March 2020-March 2022 (n=53077), were analyzed using the phylo-geo haplotype network approach with reference to the Wuhan prototype sequence. Results On haplotype analysis, 420 haplotypes were revealed from 643 segregating sites among the sequences. Haplotype sharing was noted among the strains from different geographical regions. Nevertheless, the genetic distance among the viral haplotypes from different clades could differentiate the strains into distinct haplo groups regarding variant emergence. Interpretation & conclusions The haplotype analysis revealed that the G and GR clades were co-evolved and an epicentrefor the evolution of the GH, GK and GRA clades. GH was more frequently identified in northern parts of India than in other parts, whereas GK was detected less in north India than in other parts. Thus, the network analysis facilitated a detailed illustration of the pathways of evolution and circulation of SARS-CoV-2 variants. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Appearance of Modern Ecological Pyramids: Summing Up
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Lekevičius, Edmundas and Lekevičius, Edmundas
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- 2022
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5. Life’s Attractors Continued: Progress in Understanding Developmental Systems Through Reverse Engineering and In Silico Evolution
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Crombach, Anton, Jaeger, Johannes, and Crombach, Anton, editor
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- 2021
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6. Niche Construction
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Albuquerque, Ulysses P., Magalhães, Arthur R., and Gusmão, Reginaldo A.F.
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- 2013
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7. Comparative Whole Genome Analysis of Escherichia coli O157:H7 Isolates From Feedlot Cattle to Identify Genotypes Associated With the Presence and Absence of stx Genes.
- Author
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Jia, Mo, Geornaras, Ifigenia, Martin, Jennifer N., Belk, Keith E., and Yang, Hua
- Subjects
ESCHERICHIA coli O157:H7 ,COMPARATIVE genomics ,GENES ,GENOTYPES ,GENOMES ,BEEF cattle - Abstract
A comparative whole genome analysis was performed on three newly sequenced Escherichia coli O157:H7 strains with different stx profiles, previously isolated from feedlot cattle [C1-010 (stx1− , stx2c +), C1-057 (stx−), and C1-067 (stx1 +, stx2a +)], as well as five foodborne outbreak strains and six stx -negative strains from NCBI. Phylogenomic analysis demonstrated that the stx2c -carrying C1-010 and stx -negative C1-057 strains were grouped with the six NCBI stx -negative E. coli O157:H7 strains in Cluster 1, whereas the stx2a -carrying C1-067 and five foodborne outbreak strains were clustered together in Cluster 2. Based on different clusters, we selected the three newly sequenced strains, one stx2a -carrying strain, and the six NCBI stx -negative strains and identify their prophages at the stx insertion sites. All stx -carrying prophages contained both the three Red recombination genes (exo , bet , gam) and their repressor cI. On the other hand, the majority of the stx -negative prophages carried only the three Red recombination genes, but their repressor cI was absent. In the absence of the repressor cI , the consistent expression of the Red recombination genes in prophages might result in more frequent gene exchanges, potentially increasing the probability of the acquisition of stx genes. We further investigated each of the 10 selected E. coli O157:H7 strains for their respective unique metabolic pathway genes. Seven unique metabolic pathway genes in the two stx2a -carrying strains and one in the single stx2c -carrying and seven stx -negative strains were found to be associated with an upstream insertion sequence 629 within a conserved region among these strains. The presence of more unique metabolic pathway genes in stx2a -carrying E. coli O157:H7 strains may potentially increase their competitiveness in complex environments, such as feedlot cattle. For the stx2c -carrying and stx -negative E. coli O157:H7 strains, the fact that they were grouped into the same phylogenomic cluster and had the same unique metabolic pathway genes suggested that they may also share closely related evolutionary pathways. As a consequence, gene exchange between them is more likely to occur. Results from this study could potentially serve as a basis to help develop strategies to reduce the prevalence of pathogenic E. coli O157:H7 in livestock and downstream food production environments. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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8. Evolutionary Pathways of T-Phase Transition Metal Dichalcogenides: A Comprehensive Study of Pt x Se y Clusters.
- Author
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Zhang A, Zhang M, Han T, Su H, Guo W, Ren H, Ding F, and Zhao W
- Abstract
Understanding the transition from nonplanar to planar clusters is crucial for the controllable synthesis of transition metal dichalcogenide (TMDC) monolayers. Using PtSe
2 as a model, we investigate how the chemical environment influences the nucleation and growth stages of monolayer PtSe2 through structure searching and first-principles calculations. We established a comprehensive database of platinum selenide clusters (Ptx Sey , x = 1-10), analyzing 2095 unique clusters and identifying 191 stable isomers and 63 structures with the lowest formation energy on the convex hull. Our findings reveal a chemical environment-dependent phase transition from 3D structures to the planar T-phase of Ptx Sey clusters, representing an evolutionary route for PtSe2 growth. Clusters such as PtSe6 , Pt2 Se9 , Pt3 Se10 , and Pt7 Se10 in Pt-rich environments, as well as Pt2 Se15 and Pt10 Se32 in Se-rich environments, have been found to exhibit high stability. Additionally, the impact of varying chemical potentials of Pt and Se on the stability of these clusters is explored. PtSe4 and PtSe6 are found to be highly stable under most experimentally achievable chemical potential conditions and may serve as dominant precursors during PtSe2 growth. This work advances our understanding of the nucleation processes of PtSe2 and other T-phase TMDC materials.- Published
- 2024
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9. The evolution of extended parental care in glassfrogs: Do egg‐clutch phenotypes mediate coevolution between the sexes?
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Delia, Jesse, Bravo‐Valencia, Laura, and Warkentin, Karen M.
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OVIPARITY , *ANIMAL offspring sex ratio , *COEVOLUTION , *ANIMAL clutches , *ENVIRONMENTAL risk , *FAMILY relations , *COMPARATIVE literature - Abstract
Many animals improve offspring survival through parental care. Research on coevolution between parents has provided key insight into the genesis and maintenance of biparental care. However, understanding family dynamics more broadly requires assessing potential male–female coevolutionary processes in the more widespread and common context of uniparental care. Here, we explore how pre‐zygotic maternal contributions, jelly coats and oviposition sites, influence offspring dependency and change with the evolution of male‐only care in glassfrogs. Egg care appears ubiquitous among glassfrogs, with repeated evolutionary transitions from brief female‐only to extended male‐only care. Glassfrogs also exhibit a diversity of sex‐specific parental traits involving maternal egg‐jelly contributions, oviposition‐site choice, and egg‐attendance behaviors. We hypothesize these form functionally interchangeable suites of traits that mediate embryos' susceptibility to environmental risk. First, using parent‐removal field experiments, egg‐hydration assays, and comparative analyses, we found no evidence that evolutionary transitions in caring sex or care duration alter the adaptive functions or overall benefits of care (across eight species). Rather, the jelly contributions and oviposition‐site use associated with brief care influence embryo susceptibility to the same risks that are reduced by prolonged care. Next, we examined the diversity and evolutionary history of pre‐ and post‐zygotic parental traits, applying phylogenetic comparative methods to literature records and our field observations of 40 species (71 total, ~ 47 % of the family). Because pre‐zygotic maternal contributions determine embryo requirements, the evolution of male care might enable and/or compensate for reduced maternal contributions. Supporting this hypothesis, we found that the repeated evolution of complex male care is always associated with reductions in egg‐jelly and changes in oviposition sites. This phylogenetic pattern suggests that clutch phenotype might provide a general mechanism for the coevolution of parental investment in species with uniparental care. If different combinations of egg phenotypes and post‐zygotic care are ecologically equivalent, their interchangeability could allow parental traits to coevolve between the sexes without compromising offspring survival. Male‐only care is widespread in oviparous metazoans, occurring among annelids, molluscs, arthropods, fishes, and amphibians. Investigations of egg and clutch phenotypes offer new prospects for broadening research on the coevolutionary dynamics of parental care. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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10. Root Diseases and Exotic Ecosystems: Implications for Long-Term Site Productivity
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Garbelotto, M.
- Published
- 1997
11. The Bio-Evolutionary Anthropocene Hypothesis: Rethinking the Role of Human-Induced Novel Organisms in Evolution.
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Pena Rodrigues, Pablo José Francisco and Lira, Catarina Fonseca
- Abstract
Anthropogenic changes in the biosphere, driven mainly by human cultural habits and technological advances, are altering the direction of evolution on Earth, with ongoing and permanent changes modifying uncountable interactions between organisms, the environment, and humankind itself. While numerous species may go extinct, others will be favored due to strong human influences. The Bio-Evolutionary Anthropocene hypothesizes that directly or indirectly human-driven organisms, including alien species, hybrids, and genetically modified organisms, will have major roles in the evolution of life on Earth, shifting the evolutionary pathways of all organisms through novel biological interactions in all habitats. We anticipate that, in future scenarios, novel organisms will be continuously created, and contemporary native organisms with no obvious economic use will decline—while anthropogenic-favored and novel organisms will spread. The Bio-Evolutionary Anthropocene hypothesis therefore predicts that humankind and novel organisms will interact within a strong evolutionary bias that will lead to unexpected, and probably irreversible, outcomes for the evolution of life on our planet. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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12. Origin and Development of Hair Cell Orientation in the Inner Ear
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Sienknecht, Ulrike J., Fay, Richard R., Series editor, Popper, Arthur, Series editor, Köppl, Christine, editor, Manley, Geoffrey A., editor, and Popper, Arthur N., editor
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- 2014
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13. Evolution of the Charrs, Genus Salvelinus (Salmonidae). 2. Sympatric Inner-lake Diversification (Ecological Peculiarities and Evolutionary Mechanisms Illustrated by Different Groups of Fish).
- Author
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Markevich, G. N. and Esin, E. V.
- Abstract
To date a considerable amount of data on sympatric diversification of the laсustrine fish has been accumulated and many important advances made. However, the evolutionary mechanisms of the process still remain unclear. The paper discusses fish polymorphism in the water bodies of different latitudes, but the major focus is the question of sympatry in the charrs of the genus Salvelinus across the northern lakes. Numerous cases of diversification were comparatively analyzed, which provides evidence for the existence of several main pathways of evolutionary process. The pathways are controlled by environmental factors, which determine the structure of the lake ecosystems in the northern latitudes. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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14. Evolutionary Dynamics in the RNA Bacteriophage Qβ Depends on the Pattern of Change in Selective Pressures
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Pilar Somovilla, Susanna Manrubia, and Ester Lázaro
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RNA viruses ,bacteriophage Qβ ,adaptation ,pattern of change ,fitness dynamics ,evolutionary pathways ,genetic diversity ,Medicine - Abstract
The rate of change in selective pressures is one of the main factors that determines the likelihood that populations can adapt to stress conditions. Generally, the reduction in the population size that accompanies abrupt environmental changes makes it difficult to generate and select adaptive mutations. However, in systems with high genetic diversity, as happens in RNA viruses, mutations with beneficial effects under new conditions can already be present in the population, facilitating adaptation. In this work, we have propagated an RNA bacteriophage (Qβ) at temperatures higher than the optimum, following different patterns of change. We have determined the fitness values and the consensus sequences of all lineages throughout the evolutionary process in order to establish correspondences between fitness variations and adaptive pathways. Our results show that populations subjected to a sudden temperature change gain fitness and fix mutations faster than those subjected to gradual changes, differing also in the particular selected mutations. The life-history of populations prior to the environmental change has great importance in the dynamics of adaptation. The conclusion is that in the bacteriophage Qβ, the standing genetic diversity together with the rate of temperature change determine both the rapidity of adaptation and the followed evolutionary pathways.
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- 2019
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15. Evolutionary Pathways in Soil-Geomorphic Systems.
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Phillips, Jonathan D.
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GEOMORPHOLOGY ,SOIL ecology ,LANDFORMS ,SURFACE of the earth ,EVOLUTIONARY theories - Abstract
Understanding evolution of soils and landforms (and other Earth surface systems) has itself evolved from concepts of single-path, single-outcome development to those that recognize multiple possible developmental trajectories and different maturely developed states. Soil geomorphology and pedology should now move beyond showing that multiple trajectories are possible to investigating why some evolutionary pathways (EPs) are common and persistent, whereas others are rare and transient. A typology of EPs is developed and applied to soil formation in the North Carolina coastal plain. Some EPs are impossible because of violation of generally applicable laws or absence of necessary conditions; others are currently impossible, having occurred in the past but requiring conditions that no longer exist. Improbable paths are possible but rare, because necessary circumstances involve rare events or boundary conditions. Inhibited EPs are also possible but rare because of resistance factors or feedbacks that prevent or inhibit them. Transient paths may be common but are not long-lived or well preserved and are thus rarely observed. Recurring but nonrepeating EPs occur in different locations but are irreversible in any given location and cannot recur except in the case of system-resetting disturbance or new inputs. Recurring EPs are not inhibited or self-limited, occur in different locations, and may be repeated because of ongoing or recurrent processes or conditions. Selected path types occur in multiple situations, but with increased probability due to feedbacks or responses that encourage or enhance recurrence and/or persistence. The case study shows examples of all possible EP types. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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16. To See, or Not to See, That Is the Question: Studying Dutch Experimentalist Energy Transition Governance through an Evolutionary Lens
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Martijn Gerritsen, Henk-Jan Kooij, Martijn Groenleer, and Erwin van der Krabben
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evolutionary governance ,Environmental effects of industries and plants ,experimentalist governance ,contingency ,evolutionary pathways ,path- and context-mapping ,regional energy transition ,The Netherlands ,Renewable Energy, Sustainability and the Environment ,Geography, Planning and Development ,TJ807-830 ,Management, Monitoring, Policy and Law ,TD194-195 ,Renewable energy sources ,Environmental sciences ,GE1-350 ,Institute for Management Research - Abstract
Experimentalist forms of governance have burgeoned across policy areas and institutional contexts in recent years. Recognizing that experimentalist forms of governance can evolve along a plethora of distinct pathways, this paper inquires how the evolutionary nature of experimentalism can be explored in greater depth. Linking the framework of experimentalist governance to that of Evolutionary Governance Theory (EGT), the paper identifies three driving mechanisms of contingency in experimentalism: governance being (1) self-referential, (2) rooted in observation, and (3) steered by dependencies. The paper then refers to recent efforts in the realm of energy transition governance in the Netherlands to illustrate how these contingency mechanisms can help to interrogate the variegated evolutionary pathways that experimentalist governance may have in practice. Building on this Dutch empirical context, the paper puts forward evolutionary path- and context-mapping as a fruitful tool for identifying and disentangling the myriad of pathways along which experimentalism may manifest itself.
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- 2022
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17. Inference of fitness values and putative appearance time points for evolvable self-replicating molecules from time series of occurrence frequencies in an evolution reactor.
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Aita, Takuyo, Ichihashi, Norikazu, and Yomo, Tetsuya
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BIOLOGICAL fitness , *MOLECULAR biology , *BIOLOGICAL evolution , *RNA replicase , *RNA sequencing , *STATISTICAL sampling - Abstract
We have established a translation-coupled RNA replication system within a cell-like compartment, and conducted an experimental evolution of the RNA molecules in the system. Then, we obtained a time series of occurrence frequencies of 91 individual genotypes through random sampling and next-generation sequencing. The time series showed a complex clonal interference and a polymorphic population called the “quasispecies”. By fitting a deterministic kinetic model of evolvable simple self-replicators to the time series, we estimated the fitness value and “putative appearance time point” for each of the 91 major genotypes identified, where the putative appearance time point is defined as a certain time point at which a certain mutant genotype is supposed to appear in the deterministic kinetic model. As a result, the kinetic model was well fitted and additionally we confirmed that the estimated fitness values for 11 genotypes were considerably close to the experimentally measured ones ( Ichihashi et al., 2015 ). In this sequel paper, with the theoretical basis of the deterministic kinetic model, we present the details of inference of the fitness values and putative appearance time points for the 91 genotypes. It may be possible to apply this methodology to other self-replicating molecules, viruses and bacteria. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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18. In vitro evolucija holesterol-vezavne domene z uporabo lipidnih membran
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Šakanović, Aleksandra and Anderluh, Gregor
- Subjects
ribosomal display ,od holesterola odvisni citolizini,perfringolizin O ,udc:601.4:575.224.4:602.6:557.087/.88(043.3) ,evolucijske poti ,In vitro evolution ,evolutionary pathways ,interakcije proteinov in membranskih lipidov ,In vitro evolucija ,cholesterol dependent cytolysins ,ribosomski prikaz ,cholesterol-binding domain ,protein-membrane lipid interactions ,gene libraries ,perfringolysin O ,holesterol-vezavna domena ,genske knjižnice - Abstract
S spremembami genskega materiala so skozi proces evolucije nastale značilne interakcijske površin bioloških molekul, ki z medsebojnim delovanjem usmerjajo fiziološke procese. Veliko interakcijsko platformo številnih proteinov predstavljajo biološke membrane. Periferni membranski proteini lahko specifično prepoznajo membranske lipide in so pogosto vpleteni v mehanizme napada in obrambe. Veliko skupino virulentnih dejavnikov po Gramu pozitivnih bakterij predstavljajo toksini iz družine od holesterola odvisnih citolizinov, katerih arhetipski predstavnik je erfringolizin O iz bakterije Clostridium perfringens. Začetni kontakt vodotopnih monomerov toksina omogočajo aminokisline v zankah vezavne domene, ki delujejo kot determinanta holesterolne specifičnosti, vendar točen mehanizem prepoznave membranskega holesterola še ni pojasnjen. Tudi možna biokemijska raznolikost interakcijeske površine še ni bila opisana. S pristopom in vitro evolucije s tehniko prikaza na ribosomih ob uporabi lipidnih veziklov različne sestave, smo proučevali biokemijsko in biofizikalno raznolikost stične površine proteina perfringolizina O. Po afinitetni selekciji na vezikle z visoko vsebnostjo holesterola se predvsem obogatijo aminokisline, ki so enake ali kemijsko podobne evolucijsko ohranjenim aminokislinam, in tudi redke različice, ki predstavljajo alternativno evolucijsko pot. Po afinitetni selekciji na vezikle brez holesterola nismo zaznali jasne aminokislinske obogatitve kar kaže, da je vezavna domena toksina evolucijsko izoblikovana za specifično prepoznavo membranskega holesterola in da z vsesplošnimi zamenjavami aminokislin ni možno spremeniti specifičnosti vezave. Characteristic interaction surfaces of biological molecules have evolved through modifications of genetic material to control physiological processes through biomolecular interactions. Biological membranes represent a large interaction platform for many proteins. Peripheral membrane proteins can specifically recognize membrane lipids and are often involved in attack and defense mechanisms. Toxins from the family of cholesterol-dependent cytolysins represent a large group of virulence factors of Gram-positive bacteria, the archetypal representative of which is perfringolizine O from the bacterium Clostridium perfringens. The initial contact of the water-soluble toxin monomers is enabled by amino acids in the loops of the binding domain, which act as determinants of cholesterol specificity, although the exact mechanism of membrane cholesterol recognition remains to be elucidated. The biochemical diversity of the interaction sites has also not yet been described. Using the in vitro evolution approach with ribosome display and lipid vesicles of different composition, we investigated the biochemical and biophysical diversity of the perfringolysin O protein interaction surface. Affinity selection for cholesterol-rich vesicles mainly enriched amino acids identical or chemically similar to naturally conserved amino acids. We also identified rare variants representing an alternative evolutionary pathway. No unique amino acid enrichment was detected after affinity selection for cholesterol-free vesicles, suggesting that the binding domain of the toxin is evolutionarily adapted to specifically recognize membrane cholesterol and that amino acid substitutions in the contact surface cannot alter the specificity of the protein.
- Published
- 2021
19. Low-carbon transition pathways in the context of carbon-neutral: A quadrilateral evolutionary game analysis.
- Author
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Tian, Tingting and Sun, Shuhui
- Subjects
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CONSUMER preferences , *RENT seeking , *EVOLUTIONARY models , *QUADRILATERALS , *WHISTLEBLOWING - Abstract
In the context of carbon-neutral, countries are urging a social-wide transition to decarbonization. However, the efficiency of this transition has not been as expected due to the game of benefits among relevant players. Here, we develop a quadrilateral evolutionary game model that highlights the complex interactions at a multi-player level, including producers, regulators, third-party certifiers, and consumers, in order to analyze evolutionary pathways and stable strategies. Our results suggest that: (1) there are significant correlations among the quadrilateral game players, and the benign interactions among them will effectively drive the social-wide low-carbon transition; (2) if consumers have higher low-carbon preferences, producers will be attracted to actively choose the low-carbon transition strategy, which may form a stable portfolio strategy; (3) proper interventions, such as reducing transition costs, increasing reputation loss, and raising consumers' whistle-blowing abilities, can help promote the systematic evolution to the low-carbon state; and (4) rent-seeking behavior between producers and third-party certifiers should be strongly monitored by regulators, and higher penalties can prevent their duty dereliction. These findings provide significant implications for policy-makers to make better-informed decisions about the social-wide low-carbon transition in the context of carbon-neutral. • The evolutionary game model on low-carbon transition is constructed. • Consumers' low-carbon preference is the priority factor of transition willingness. • Strong regulation can urge producers to transit into low-carbon production. • Higher penalties to avoid collusion, higher validity of low-carbon certificates. • Whistle-blowing behavior actively affects the evolutionary system. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. Comparative Whole Genome Analysis of
- Author
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Mo, Jia, Ifigenia, Geornaras, Jennifer N, Martin, Keith E, Belk, and Hua, Yang
- Subjects
Red homologous recombination ,evolutionary pathways ,Shiga toxin-producing and stx-negative E. coli O157:H7 ,acquisition and loss of stx genes ,IS629 ,cattle ,metabolic pathway genes ,Microbiology ,whole genome analysis ,Original Research - Abstract
A comparative whole genome analysis was performed on three newly sequenced Escherichia coli O157:H7 strains with different stx profiles, previously isolated from feedlot cattle [C1-010 (stx1−, stx2c+), C1-057 (stx−), and C1-067 (stx1+, stx2a+)], as well as five foodborne outbreak strains and six stx-negative strains from NCBI. Phylogenomic analysis demonstrated that the stx2c-carrying C1-010 and stx-negative C1-057 strains were grouped with the six NCBI stx-negative E. coli O157:H7 strains in Cluster 1, whereas the stx2a-carrying C1-067 and five foodborne outbreak strains were clustered together in Cluster 2. Based on different clusters, we selected the three newly sequenced strains, one stx2a-carrying strain, and the six NCBI stx-negative strains and identify their prophages at the stx insertion sites. All stx-carrying prophages contained both the three Red recombination genes (exo, bet, gam) and their repressor cI. On the other hand, the majority of the stx-negative prophages carried only the three Red recombination genes, but their repressor cI was absent. In the absence of the repressor cI, the consistent expression of the Red recombination genes in prophages might result in more frequent gene exchanges, potentially increasing the probability of the acquisition of stx genes. We further investigated each of the 10 selected E. coli O157:H7 strains for their respective unique metabolic pathway genes. Seven unique metabolic pathway genes in the two stx2a-carrying strains and one in the single stx2c-carrying and seven stx-negative strains were found to be associated with an upstream insertion sequence 629 within a conserved region among these strains. The presence of more unique metabolic pathway genes in stx2a-carrying E. coli O157:H7 strains may potentially increase their competitiveness in complex environments, such as feedlot cattle. For the stx2c-carrying and stx-negative E. coli O157:H7 strains, the fact that they were grouped into the same phylogenomic cluster and had the same unique metabolic pathway genes suggested that they may also share closely related evolutionary pathways. As a consequence, gene exchange between them is more likely to occur. Results from this study could potentially serve as a basis to help develop strategies to reduce the prevalence of pathogenic E. coli O157:H7 in livestock and downstream food production environments.
- Published
- 2020
21. Discriminatory profile of rDNA sites and trend for acrocentric chromosome formation in the genus Trachinotus Lacépède, 1801 (Perciformes, Carangidae).
- Author
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Pereira Jacobina, Uedson, Vicari, Marcelo Ricardo, Bertollo, Luiz Antonio Carlos, and Molina, Wagner Franco
- Subjects
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FISH phylogeny , *FISH genetics , *CHROMOSOMES , *CYTOTAXONOMY , *RECOMBINANT DNA , *CARANGIDAE - Abstract
Chromosomal traits have provided valuable information for phylogeny and taxonomy of several fish groups. Three Atlantic Carangidae species of the genus Trachinotus Lacépède, 1801 (T. goodei Jordan et Evermann, 1896, T. carolinus (Linnaeus, 1766) and T. falcatus (Linnaeus, 1758)) were investigated, having 2n=48 chromosomes but different chromosomal arms (FN number), i.e., 52, 56 and 58, respectively, in view of the different number of two-armed chromosomes found in their karyotypes. Thus, T. goodei, T. carolinus and T. falcatus present a progressive distance from the probable basal karyotype proposed for Perciformes (2n=48 acrocentrics, FN=48). At first sight, these findings do not agree with the phylogenetic hypothesis based on mitochondrial sequences, where T. goodei appear as the most derived species, followed by T. falcatus and T. carolinus, respectively. However, the chromosomal mapping of ribosomal DNAs was informative for clarifying this apparent conflict. Indeed, the multiple 5S and 18S rDNA sites found in T. goodei corroborate the most derived condition for this species. In this sense, the occurrence of the unexpected number of two-armed chromosomes and FN value for this species, as well as for T. carolinus, must be due to additional rounds of acrocentric formation in these species, modifying the macrostructure of their karyotypes. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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22. Pathways of transport protein evolution: recent advances.
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Lam, Vincent H., Lee, Jong-Hoon, Silverio, Abe, Chan, Henry, Gomolplitinant, Kenny M., Povolotsky, Tatyana L., Orlova, Ekaterina, Sun, Eric I., Welliver, Carl H., and Saier, Milton H.
- Subjects
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CARRIER proteins , *MEMBRANE proteins , *ION channels , *PROTEIN structure , *CHROMOSOME replication , *BIOLOGICAL evolution - Abstract
We herein report recent advances in our understanding of transport protein evolution. Numerous families of complex transmembrane transport proteins are believed to have arisen from short channel-forming amphipathic or hydrophobic peptides by various types of intragenic duplication events. Distinct pathways distinguish families, demonstrating independent origins for some, and allowing assignment of others to superfamilies. Some families have diversified in topology, whereas others have remained uniform. An example of 'retroevolution' was discovered where a more complex carrier gave rise to a structurally and functionally simpler channel. The results described in this review article expand our understanding of protein evolution. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
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23. Temporal Constraints on the Incorporation of Regulatory Mutants in Evolutionary Pathways.
- Author
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Brown, Kyle M., DePristo, Mark A., Weinreich, Daniel M., and Hartl, Daniel L.
- Abstract
Understanding the molecular details of the sequence of events in multistep evolutionary pathways can reveal the extent to which natural selection exploits regulatory mutations affecting expression, amino acid replacements affecting the active site, amino acid replacements affecting protein folding or stability, or variations affecting gene copy number. In experimentally exploring the adaptive landscape of the evolution of resistance to β-lactam antibiotics in enteric bacteria, we noted that a regulatory mutation that increases β-lactamase expression by about 2-fold has a very strong tendency to be fixed at or near the end of the evolutionary pathway. This pattern contrasts with previous experiments selecting for the utilization of novel substrates, in which regulatory mutations that increase expression are often fixed early in the process. To understand the basis of the difference, we carried out experiments in which the expression of β-lactamase was under the control of a tunable arabinose promoter. We find that the fitness effect of an increase in gene expression is highly dependent on the catalytic activity of the coding sequence. An increase in expression of an inefficient enzyme has a negligible effect on drug resistance; however, the effect of an increase in expression of an efficient enzyme is very large. The contrast in the temporal incorporation of regulatory mutants between antibiotic resistance and the utilization of novel substrates is related to the nature of the function that relates enzyme activity to fitness. A mathematical model of β-lactam resistance is examined in detail and shown to be consistent with the observed results. [ABSTRACT FROM PUBLISHER]
- Published
- 2009
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24. To See, or Not to See, That Is the Question: Studying Dutch Experimentalist Energy Transition Governance through an Evolutionary Lens.
- Author
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Gerritsen, Martijn, Kooij, Henk-Jan, Groenleer, Martijn, and van der Krabben, Erwin
- Abstract
Experimentalist forms of governance have burgeoned across policy areas and institutional contexts in recent years. Recognizing that experimentalist forms of governance can evolve along a plethora of distinct pathways, this paper inquires how the evolutionary nature of experimentalism can be explored in greater depth. Linking the framework of experimentalist governance to that of Evolutionary Governance Theory (EGT), the paper identifies three driving mechanisms of contingency in experimentalism: governance being (1) self-referential, (2) rooted in observation, and (3) steered by dependencies. The paper then refers to recent efforts in the realm of energy transition governance in the Netherlands to illustrate how these contingency mechanisms can help to interrogate the variegated evolutionary pathways that experimentalist governance may have in practice. Building on this Dutch empirical context, the paper puts forward evolutionary path- and context-mapping as a fruitful tool for identifying and disentangling the myriad of pathways along which experimentalism may manifest itself. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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- View/download PDF
25. Evolutionary pathway of child development.
- Author
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Bereczkei, Tamas and Csanaky, Andras
- Abstract
An evolutionary theory of socialization suggests that children from father-absent families will mature earlier, and form less-stable pair bonds, compared with those from father-present families. Using a sample of about 1,000 persons the recent study focuses on elements of father-absent children's behavior that could be better explained by a Darwinian approach than by rival social science theories. As a result of their enhanced interest in male competition, father-absent boys were found to engage in rule-breaking behavior more intensively than father-present boys. Compared with father-present children, adolescents from widowed households (both boys and girls) showed a higher intensity of various kinds of noncompliant behavior, which can be linked to their earlier maturation. School attendance, age at marriage, and marital success proved to be influenced by the children's early family experiences, governed by adapted evolutionary strategies. Father-absent daughters conceived more children than those whose fathers were present during their childhood. As evolutionary theory predicts, reproductive behavior of individuals from divorced households differed from that of individuals who grew up in widowed households. Finally, the strong correlation found between spontaneous abortion/stillbirths and family arrangement indicates that father absence has certain direct impacts on the neurohormonal processes of child development. [ABSTRACT FROM AUTHOR]
- Published
- 1996
- Full Text
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26. Evolutionary Pathways and Trajectories in Antibiotic Resistance.
- Author
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Baquero F, Martínez JL, F Lanza V, Rodríguez-Beltrán J, Galán JC, San Millán A, Cantón R, and Coque TM
- Subjects
- Anti-Bacterial Agents pharmacology, Bacteria genetics, Drug Resistance, Microbial, Mutation, Phylogeny, Ecosystem, Selection, Genetic
- Abstract
Evolution is the hallmark of life. Descriptions of the evolution of microorganisms have provided a wealth of information, but knowledge regarding "what happened" has precluded a deeper understanding of "how" evolution has proceeded, as in the case of antimicrobial resistance. The difficulty in answering the "how" question lies in the multihierarchical dimensions of evolutionary processes, nested in complex networks, encompassing all units of selection, from genes to communities and ecosystems. At the simplest ontological level (as resistance genes), evolution proceeds by random (mutation and drift) and directional (natural selection) processes; however, sequential pathways of adaptive variation can occasionally be observed, and under fixed circumstances (particular fitness landscapes), evolution is predictable. At the highest level (such as that of plasmids, clones, species, microbiotas), the systems' degrees of freedom increase dramatically, related to the variable dispersal, fragmentation, relatedness, or coalescence of bacterial populations, depending on heterogeneous and changing niches and selective gradients in complex environments. Evolutionary trajectories of antibiotic resistance find their way in these changing landscapes subjected to random variations, becoming highly entropic and therefore unpredictable. However, experimental, phylogenetic, and ecogenetic analyses reveal preferential frequented paths (highways) where antibiotic resistance flows and propagates, allowing some understanding of evolutionary dynamics, modeling and designing interventions. Studies on antibiotic resistance have an applied aspect in improving individual health, One Health, and Global Health, as well as an academic value for understanding evolution. Most importantly, they have a heuristic significance as a model to reduce the negative influence of anthropogenic effects on the environment.
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- 2021
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27. Evolutionary Dynamics in the RNA Bacteriophage Qβ Depends on the Pattern of Change in Selective Pressures.
- Author
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Somovilla, Pilar, Manrubia, Susanna, and Lázaro, Ester
- Subjects
BACTERIOPHAGES ,RNA ,RNA viruses ,DERIVATIVES (Mathematics) ,ORDER picking systems - Abstract
The rate of change in selective pressures is one of the main factors that determines the likelihood that populations can adapt to stress conditions. Generally, the reduction in the population size that accompanies abrupt environmental changes makes it difficult to generate and select adaptive mutations. However, in systems with high genetic diversity, as happens in RNA viruses, mutations with beneficial effects under new conditions can already be present in the population, facilitating adaptation. In this work, we have propagated an RNA bacteriophage (Qβ) at temperatures higher than the optimum, following different patterns of change. We have determined the fitness values and the consensus sequences of all lineages throughout the evolutionary process in order to establish correspondences between fitness variations and adaptive pathways. Our results show that populations subjected to a sudden temperature change gain fitness and fix mutations faster than those subjected to gradual changes, differing also in the particular selected mutations. The life-history of populations prior to the environmental change has great importance in the dynamics of adaptation. The conclusion is that in the bacteriophage Qβ, the standing genetic diversity together with the rate of temperature change determine both the rapidity of adaptation and the followed evolutionary pathways. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
28. Convergent Plants
- Author
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McGhee, George R., author
- Published
- 2011
- Full Text
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29. From Organisational Behaviour to Industrial Network Evolutions: Stimulating Sustainable Development of Bioenergy Networks in Emerging Economies
- Author
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Kempener, Rudolf T. M
- Subjects
evolutionary pathways ,organisational behaviour ,industrial networks ,multi-scale complexity ,bioenergy ,agent-based modelling ,sustainability ,strategy ,innovation - Abstract
The aim of this thesis is to understand what drives the evolution of industrial networks and how such understanding can be used to stimulate sustainable development. A complex adaptive systems perspective has been adopted to analyse the complex interaction between organisational behaviour and industrial network evolution. This analysis has formed the basis for the development of a modelling approach that allows for quantitative exploration of how different organisational perceptions about current and future uncertainty affect their behaviour and therefore the network evolution. This analysis results in a set of potential evolutionary pathways for an industrial network and their associated performance in terms of sustainable development. Subsequently, this modelling approach has been used to explore the consequences of interventions in the network evolution and to identify robust interventions for stimulating sustainable development of industrial networks. The analysis, modelling approach and development of interventions has been developed in the context of a bioenergy network in the region of KwaZulu-Natal in South Africa. Industrial networks are an important aspect of today’s life and provide many goods and services to households and individuals all over the world. They consist of a large number of autonomous organisations, where some organisations contribute by transforming or transacting natural resources, such as oil, agricultural products or water, while other organisations contribute to networks by providing information or setting regulation or subsidies (local or national governments) or by influencing decision making processes of other organisations in networks (advocacy groups). Throughout the process from natural resource to product or service, industrial networks have important economic, environmental and social impacts on the socio-economic and biophysical systems in which they operate. The sum of complex interactions between organisations affects the rate in which natural resources are used, environmental impacts associated with transformation and transaction of resources and social impacts on local communities, regions or countries as a whole. The aim of this thesis is to understand how industrial networks evolve and how they can be stimulated towards sustainable development. The first question that has been addressed in this thesis is how to understand the complex interaction between organisational behaviour and industrial network evolution. Organisational behaviour is affected by many functional and implicit characteristics within the environment in which the organisation operates, while simultaneously the environment is a function of non-linear relationships between individual organisational actions and their consequences for both the function and structure of the network. This thesis has identified four different characteristics of industrial networks that affect organisational behaviour: 1) Functional characteristics 2) Implicit behavioural characteristics 3) Implicit relational characteristics 4) Implicit network characteristics. Functional characteristics are those characteristics that are formally recognised by all organisations within an industrial network and which affect their position within the network. Examples of functional characteristics are the price and quantity of resources available, the location and distance of organisations within a network, infrastructure availability or regulation. Implicit characteristics, on the other hand, are those characteristics that impact the decision making process of organisations, but which are not formally part of the network. From an organisational perspective, implicit characteristics are the rules, heuristics, norms and values that an organisation uses to determine its objectives, position and potential actions. Implicit relational characteristics, most importantly trust and loyalty, affect an organisations choice between potential partners and implicit network characteristics are those social norms and values that emerge through social embeddedness. Collectively, these functional and implicit characteristics and their interactions determine the outcome of organisational decisions and therefore the direction of the industrial network evolution. The complex interaction between these large numbers of characteristics requires quantitative models to explore how different network characteristics and different interactions result in different network evolutions. This thesis has developed an agent-based simulation model to explore industrial network evolutions. To represent the multi-scale complexity of industrial networks, the model consists of four scales. Each scale represents different processes that connect the functional and implicit characteristics of an industrial network to each other. The two basic scales represent the strategic actions of the organisations on the one hand and the industrial network function and structure on the other. The third scale represents the processes that take place within the mental models of organisations describing how they make sense of their environment and inform their strategic decision making process. The fourth scale represents the social embeddedness of organisations and how social processes create and destroy social institutions. The model has been developed such that it allows for exploring how changes in different network characteristics or processes affect the evolution of the network as a whole. The second question that has been addressed in this thesis is how to evaluate sustainable development of different evolutionary pathways of industrial networks. First of all, a systems approach has been adopted to explore the consequences of an industrial network to the larger socio-economic and biophysical system in which the network operates. Subsequently, a set of structural indicators has been proposed to evaluate the dynamic performance of industrial networks. These four structural indicators reflect the efficiency, effectiveness, resilience and adaptiveness of industrial networks. Efficiency and effectiveness relate to the operational features by which industrial networks provides a particular contribution to society. Resilience and adaptiveness relate to the system’s capacity to maintain or adapt its contribution to society while under stress of temporary shocks or permanent shifts, respectively. Finally, different multi-criteria decision analysis (MCDA) tools have been applied to provide a holistic evaluation of sustainable development of industrial networks. The third important question that is addressed in this thesis is how to systematically explore the potential evolutionary pathways of an industrial network, which has led to the development of agent-based scenario analysis. Agent-based scenario analysis systematically explores how industrial network evolutions might evolve depending on the perceptions of organisations towards the inherent uncertainty associated with strategic decision making in networks. The agent-based scenario analysis consists of two steps. Firstly, analysts develop a set of coherent context scenarios, which represents their view on the context in which an industrial network will operate within the future. For a bioenergy network, for example, this step results in a set of scenarios that each represent a coherent future of the socio-economic system in which the network might evolve. The second step is the development of a set of ‘agent scenarios’. Each agent-based scenario is based on a different ‘mental model’ employed by organisations within the network about how to deal with the inherent ambiguity of the future. The organisational perspective towards uncertainty is of major importance for the evolution of industrial networks, because it determines the innovative behaviour of organisations, the structure of the network and the direction in which the network evolves. One the one hand, organisations can ignore future ambiguity and base their actions on the environment that they can observe in their present state. On the other extreme, organisations can adopt a view that the future is inherently uncertain and in which they view social norms and values more important than functional characteristics to make sense of their environment. The mental models are differentiated according to two dimensions: 1) different mental representation of the world and 2) different cognitive processes that can be employed to inform strategic actions. Along these dimensions, different processes can be employed to make sense of the environment and to inform decision making. The thesis has shown that by systematically exploring the different perceptions possible, an adequate understanding of the different evolutionary pathways can be gained to inform the evaluation and development of interventions to stimulate sustainable development. The final part of this thesis has applied the analysis and methodology developed throughout this thesis to a bioenergy network in the province of Kwazulu-Natal in South Africa. The bioenergy network consists of a set of existing sugar mills with large quantities of bagasse, a biomass waste product, available. Bagasse is currently burned inefficiently to produce steam for the sugar mills, but can potentially be used for the production of green electricity, biodiesel, bioethanol or gelfuel. All of these products have important consequences for the region in terms of associated reductions in CO2 emissions, electrification of and/or energy provision for rural households and local economic development of the region. This thesis has modelled strategic decisions of the sugar mills, the existing electricity generator, potential independent energy producers, local and national governments and how their actions and interactions can lead to different evolutionary pathways of the bioenergy network. The agent-based scenario analysis has been used to explore how different perceptions of organisations can lead to different network evolutions. Finally, the model has been used to explore the consequences of two categories of interventions on stimulating sustainable development. The conclusions are that both categories of interventions, financial interventions by national government and the introduction of multi-criteria decision analysis (MCDA) tools to aid strategic decision making, can have both positive and negative effects on the network evolutions, depending on what ‘mental models’ are employed by organisations. Furthermore, there is no single intervention that outperforms the others in terms of stimulating both functional and structural features of sustainable development. The final conclusion is that instead of focusing on individual or collective targets, emphasis should be placed on the development of interventions that focus on evolutionary aspects of industrial networks rather than functional performance criteria. This thesis has also highlighted interesting research questions for future investigation. The methodology developed in this thesis is applied to a single case study, but there are still many questions concerning how different industrial networks might benefit from different organisational perceptions towards uncertainty. Furthermore, the role between the mental models and sustainable development requires further investigation, especially in the light of globalisation and the interconnectiveness of industrial networks in different countries and continents. Finally, this methodology has provided a platform for investigating how new technologies might be developed that anticipate needs of future generations. This thesis has provided a first and important step in developing a methodology that addresses the complex issues associated with sustainable development, benefiting both academics and practitioners that aim to stimulate sustainable development.
- Published
- 2008
30. Ecology and evolution of parent–embryo interactions in neotropical glassfrogs
- Author
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Delia, Jesse
- Subjects
- Evolution & development, Centrolenidae, Embryo behavior, Evolutionary pathways, Hatching plasticity, Parental care, Sexual selection
- Abstract
Parental care is important to offspring survival in many species. Because care benefits young and is often costly to parents, it can generate fitness trade-offs that influence the evolution of family life. In particular, interactions within families are predicted to generate variation in care, which in turn causes selection on traits used to give, receive, and influence care. My dissertation examines whether such socially dynamic processes have influenced the evolution of parental and embryo behavior in glassfrogs (Centrolenidae). These Neotropical frogs have terrestrial eggs, aquatic larvae, and multiple origins of male-only care. Embryos can plastically alter hatching age, which might allow them to adaptively respond to variation in egg care. I test for parent–embryo coevolution by combining field observations (40 species), experiments (8 species), and phylogenetic comparative analyses. First, I test historical and functional hypotheses of parental care evolution. I found that uniparental egg-care is ubiquitous in centrolenids, can be provided by either sex, and benefits young. Elaborate male-only care evolved repeatedly from simpler female-only care, a pattern consistent with constraints on female-care levels. Second, I examine the diversification of male-only care, testing whether maternal changes to egg-clutch traits influence embryo dependency and if such changes are associated with male-only care. Evidence indicates that reduced female expenditure on egg-jelly evolved with, and increases the importance of, elaborate male care. Next, I evaluate whether embryos respond to behavioral and evolutionary changes in parenting. Embryos behaviorally delay hatching when parents continue caring, and evidence indicates that evolutionary increases in hatching plasticity evolved with increases in care duration. I tested if male mating success causes variation in male care, and thereby influences embryo behavior. I found that increased mating success extends male care, making nests safer, and embryos delay hatching accordingly. Finally, I examine selective tradeoffs influencing hatching plasticity by measuring hatchling phenotypes and fitness correlates. Across species, delayed hatching provides performance benefits during the larval stage. Overall, my work reveals coevolutionary interactions among mothers, fathers, and embryos. It supports that embryos respond to parentally mediated changes in egg environments and elucidates how family life alters selection on parental and embryo traits.
- Published
- 2018
31. Variation in sexual expression in Jacaratia mexicana (Caricaceae) in southern Mexico : Frequency and relative seed performance of fruit-producing males
- Author
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Aguirre, A., Vallejo-Marin, M., Salazar-Goroztieta, L., Arias, D. M., Dirzo, R., Aguirre, A., Vallejo-Marin, M., Salazar-Goroztieta, L., Arias, D. M., and Dirzo, R.
- Abstract
Dioecy, the segregation of male and female structures among individuals, is widespread in tropical plants, encompassing 10-30 percent of species in some sites. In many cases, interindividual sex separation is not complete, as individual plants, although nominally dioecious, may produce both types of reproductive structures. A common form of this sexual variation is the production of female structures in otherwise male individuals, commonly referred to as fruiting males. Here we report the existence of fruiting males in the dioecious tropical tree Jacaratia mexicana (Caricaceae). We show that fruiting males can constitute up to 45 percent of all males in some populations of a tropical forest in Southern Mexico. In order to determine the functional significance of fruiting males for the breeding system of J. mexicana, we compared the relative performance of male- and female-borne seeds. Our results show that seeds from fruiting males are three times less likely to germinate and survive than seeds from female trees. Based on relative seed fitness data, and sex ratios in natural populations, we estimate that 6-15 percent of the genes contributed by fruiting males to the next generation are transmitted via ovules, meaning that morphological variation in gender is at least partially accompanied by functional gender variation. Finally, our seed fitness estimates for fruiting males suggest that fruiting males will not replace female plants in natural populations., Times Cited: 0 Cited Reference Count: 39
- Published
- 2007
32. The breeding of the cultivated potato species solanum x juzepczukii and S. x curtilobum II. The resynthesis of S. x juzepczukii and S. x curtilobum
- Author
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Schmiediche, P. E., Hawkes, J. G., and Ochoa, C. M.
- Published
- 1982
- Full Text
- View/download PDF
33. The Evolution of Sexual Dimorphism in Parasitic Cuckoos: Sexual Selection or Coevolution?
- Author
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Krüger, O., Davies, N. B., and Sorenson, M. D.
- Published
- 2007
- Full Text
- View/download PDF
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