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Question: Hardy-Weinberg equilibrium is known to be affected by gene flow, genetic drift, mutation, genetic re...

Hardy-Weinberg equilibrium is known to be affected by gene flow, genetic drift, mutation, genetic recombination and
A) Evolution
B) Limiting factors
C) Saltation
D) Natural selection
E) Over prediction

Explanation

Solution

The Hardy-Weinberg equilibrium is a theory that, in the absence of disturbing causes, genetic diversity in the population will remain stable from one generation to the next. E.g., mutations disturb the balance of allele frequencies in a population by adding new alleles.

Complete answer:
i) The Hardy-Weinberg equilibrium is a theory that, in the absence of disturbing causes, genetic diversity in the population will remain stable from one generation to the next.
ii) When mating is spontaneous in a large population with no destructive conditions, the rule assumes that both the genotype and the allele frequencies will stay stable since they are in balance.
iii) The Hardy-Weinberg balance can be disrupted by a variety of forces, like non-random mating, natural selection, genetic drift, mutations, and gene flow. E.g., mutations disturb the balance of allele frequencies by adding new alleles into the population.
iv) Similarly, natural selection and non-random mating disturb the balance of Hardy-Weinberg due to shifts in gene frequency.
v) This is how such alleles support or impair the reproductive success of the species that bear them.
vi) Another aspect that can disrupt this balance is genetic drift, which happens as allele frequencies rise higher or lower by chance and usually occur in small populations.
vii) Gene flow, which happens when mating between two species introduces new alleles to a population, may also change the Hardy-Weinberg equilibrium.

Additional information: The results of the Hardy-Weinberg Theorem apply only if the population complies with the basic assumption:
i) Natural selection would not work on the position in question (i.e., there are no consistent differences in probabilities of survival or reproduction among genotypes).
ii) Neither mutation (the origin of new alleles) nor migration (the transfer of individuals and their genes in and out of the population) brings new alleles into the population.
iii) Population size is infinite, that means that genetic drift does not induce random variations in allele frequency due to sampling error from generation after generation. Of course, all-natural ecosystems are limited and thus subject to drift, although we consider the consequences of drift to be more prominent in small populations than in huge populations.
iv) Individuals in the population mate spontaneously with reference to the place in question. Although non-random mating does not shift allele frequencies through one generation towards the next if the other assumptions hold, it can produce differences from the predicted genotype frequencies, and this can set the stage for natural selection to affect evolutionary change.

Hence, the correct answer is an option (D) 'Natural selection'.

Note: Since many of these destructive forces generally exist in nature, the Hardy-Weinberg balance rarely occurs in practice. Thus, the Hardy-Weinberg equilibrium represents an idealized state, and hereditary differences in nature can be calculated as changes in this equilibrium state.