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Disturbance and Stress in Coastal Ecosystems
Published in Vineet Kumar, Vinod Kumar Garg, Sunil Kumar, Jayanta Kumar Biswas, Omics for Environmental Engineering and Microbiology Systems, 2023
Milton Torres-Ceron, Joshua Lerner, Antonio Leija-Tristan, Juan Antonio Vidales-Contreras
Alternatively, if disturbance-induced mortality is random or non-selective, genetic diversity is likely reduced through genetic drift. Drift alters the allele frequency of a population through random sampling of the gene pool and may lead to the fixation or loss of genotypes, especially rare variants (Star and Spencer 2013). Coastal ecosystems such as estuaries and tidal wetlands, however, are open to both the ocean and the rivers that feed into them, which facilitates rapid migration and dispersal for organisms that rely on the buoyancy and movement of water associated with tides, wind, and currents (Costanza, Kemp, and Boynton 1993). Therefore, gene flow from exogenous sources can quickly replenish a population’s gene pool following a disturbance. Since functional replacements for those lost in the disturbance are nearly always available, the selective advantages of specialization are minimal, and most organisms are r-selected generalists. These organisms are highly fecund and resilient opportunists capable of filling a variety of functional roles and niches. In ecosystems that experience such frequent unpredictable disturbances, there is a lack of a stable base on which taxonomic diversity can develop, so there is no need for a specialized function. Rather, functional generalists, such as oysters, crabs, shrimp, and bass, and other dominant organisms help maintain resilience by maintaining keystone ecological processes under changing conditions.
IoE-Based Genetic Algorithms and Their Requisition
Published in Suhel Ahmad Khan, Rajeev Kumar, Omprakash Kaiwartya, Mohammad Faisal, Raees Ahmad Khan, Computational Intelligent Security in Wireless Communications, 2022
Neeraj Kumar Rathore, Shubhangi Pande
In a biological sense, the smallest unit of life is a human/animal cell. The cell nucleus can be demonstrated as the center of the cell. The information related to genetics is stored in the cell nucleus. In the nucleus, there is a nuclear envelope, within this, there is a nucleolus and a set of chromosomes. Chromosomes hold on to all the genetic data. Every chromosome is built up of DNA (deoxyribonucleic acid). Genes can be stated as the division of several parts of chromosomes. Alleles can be demonstrated as the plausibility of gene aggregation for one property, and distinct alleles constitute a gene. Take into account a gene that determines eye color, and the numerous allele possibilities are brown, black, green, and blue. A gene pool is defined as the collection of all possible alleles found in a population. The gene pool can regulate all the probable divergence for upcoming generations [3–15].
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Published in Carl W. Hall, Laws and Models, 2018
Keywords: electrical, capacitors, resistors Sources: Fink, D. G. and Beaty, H. W. 1993; Isaacs, A. 1996; Mandel, S. 1972. See also PARALLEL (RESISTANCES) SEWALL WRIGHT LAW OR EFFECT (1931); ALSO KNOWN AS GENETIC DRIFT A random process as a result of a chance factor in evolution, tied to the size of a breeding population, particularly due to fluctuation of allele frequencies in a small population. If a small population becomes reproductively isolated, its gene pool may no longer represent the range of genetic diversity found in the parent pool. The smaller the breakaway population, the greater the effect of genetic drift. This law was first described by Sewall Wright. Genetic drift is one of the factors that can disturb the Hardy-Weinberg equilibrium. Keywords: evolution, gene, isolated, population WRIGHT, Sewall, 1889-1988, American geneticist Sources: Barr, E. S. 1973; Gray, P. 1967; Milner, R. 1990; Tootill, E. 1981. 1988. See also EVOLUTION; GENETIC DRIFT; HARDY-WEINBERG SHANNON LAW OR FORMULA OR THEOREM (1948) The information transmitted from a message source over a communications system is represented by: C = W log2(1 + P/N) where C = channel capacity in bits per second W = bandwidth
Stability of multidimensional systems using bio-inspired meta-heuristics
Published in International Journal of Control, 2018
E. J. Solteiro Pires, P. B. de Moura Oliveira, J. A. Tenreiro Machado
Another important operator is the mutation operator (Goldberg, 1989) which alters one or more gene values in the chromosome changing its initial value. This process can introduce new genetic material resulting in entirely new gene values being added to the gene pool. With these new alleles values, the GA may be able to find better solutions. Mutation occurs during evolution according to a user-defined mutation probability (). When using the binary encoding implementation, a popular mutation operator is the flip-bit which consists in inverting the value of the chosen gene to its complementary value. Figure 3 shows an example of this operator. Bit 5 is chosen to be mutated. So, if its initial value is ‘1’, then it is changed to its complementary value ‘0’.
Transhumanist Genetic Enhancement: Creation of a ‘New Man’ Through Technological Innovation
Published in The New Bioethics, 2021
To avoid some of the problems with the classical definition of eugenics, a simpler one has been proposed: ‘Eugenics is the attempt to improve the human gene pool’ (Wilkinson and Garrard 2013, p. 2). This definition of eugenics requires (a) an explanation of the meaning of ‘improving the human gene pool’, (b) a moral justification for attempting to improve the gene pool, and (c) what form, if any, of this attempt can be morally acceptable (Wilkinson and Garrard 2013).