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It seems logical that natural selection would work toward genetic uniformity; the genotypes that are most fit produce the most offspring, increasing the frequency of adaptive alleles and eliminating less adaptive alleles. Yet there remains a great deal of
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- An allele A is present in a population at a frequency of 0.29, and there is only one other allele at the same locus. Fitness is associated with variation at the locus carrying the A allele such that there is a selection coefficient s equal to 0.03. What would you expect the frequency of the A allele to be after one generation of natural selection. Compute your result up to four decimal places.arrow_forwardWhich of the following comparisons between natural and sexual selection between is FALSE? O Variation underlying traits must have a genetic basis and be heritable under both natural and sexual selection. Under sexual selection, fitness is defined in terms of offspring number, whereas under natural selection offspring number and survuval influence fitness. Both natural and sexual selection require variation in traits that affect fitness. Under natural selection, fitness is compared across all individuals within a population, whereas for sexual selection comparisons of fitness are only relevant among individuals within a given sex (i.e., males only or females only).arrow_forwardIf gene A/a is not in Hardy-Weinberg equilibrium due to natural selection such that individuals with the genotype AA have a fitness value of 1.0, heterozygotes have only slightly reduced fitness at 0.9, and individuals with the genotype aa have a fitness value of 0.6, what kind of change in allele frequency would you expect to see over time assuming you start with equal frequencies of the 2 alleles?arrow_forward
- Which of the following is likely to be observed if there has been a strong positive selection on a particular genetic locus within a population? Group of answer choices There will be a lot of variation in DNA surrounding the genetic locus in question within the population. There will very little variation in DNA surrounding the genetic locus in question within the population. You will see very low frequencies of the genetic locus in questionarrow_forwardA population of birds has two alleles encoding for three different phenotypes: long wings, wingsss, and mid-length wings. . The initial frequency of the Sallele was 0.63 and the sallele was 0.37. However 97% of the long-winged birds survived to reproductive age56% of mid-length birds survived to reproductive age, and only 10% of short-winged birds survived to reproductive age. You are going to determine if natural selection has an effect on the allele frequency What is the expected frequency of the Sallele in the next generation when you incorporate the survival rate? Please use as many decimals points as possible when doing your calculations. Please answer using four decimal points. (Your population can be 100 or 1000 individuals or any numberreally up to you.I work with 1000but that won't change the results because we are talking about frequency.)arrow_forwardWhat are the similarities and differences between natural selection and selective breeding?arrow_forward
- Much attention is given to the existence of genetic variation in populations.Why do evolutionary biologists give so much attention to this? Explain mechanisms thatgenerate genetic variation in populations. Explain mechanisms that maintain geneticvariation in populations. Provide examples and dataarrow_forwardThree genotypes occur in a population of birds: DD, Dd, and dd. D is the dominant allele, and encodes the dark - coloured birds; light - coloured mice have the genotype dd. There are initially 60 DD, 60 Dd, and 60 dd birds in a population, and the selection coefficient against light - coloured birds is 0.4. If 80% of each dark - coloured genotype survives (48 DD and 48 Dd), how many light-coloured birds would you expect to see in the next generation?arrow_forwardWhich of the following statements about genetic fitness and/or selection is false? Group of answer choices Individuals with low fitness have greater selection coefficients Fitness involves both relative viability and reproductive success Individuals with high fitness have greater selection coefficients Selection against recessive alleles tends to be slower overall than dominant alleles because of the survival in heterozygotesarrow_forward
- if gametes from a gene pool combine randomly to make only a small number of zygotes, the allele frequencies among the zygotes may be quite different than they are in the gene pool, why? (choose one from below) 1. the effects of natural selection are more pronounced in small populations 2.changed in allele frequencies over many generations are inevitable with sexual reproduction 3. alleles combine more randomly with a small number of zygotes 4. the effects of sampling error are more pronounced with smaller samplesarrow_forwardWhich of these scenarios is an example of disruptive selection? Darker colored morphs in a butterfly population are more adaptive than lighter colored morphs, and lighter colored morphs are eliminated from the population. Intermediate gray morphs of a butterfly population are maintained, and the extreme dark and light color morphs have been eliminated. The dark and light color morphs of a butterfly population are maintained, and the intermediate gray morph has been eliminated from the population. A new, unique color form arises from a mutation in a population of butterflies.arrow_forwardAt least one of the discoverers of this genetic equilibrium (Hardy) developed this HW equation to show that the dominant allele will not always take over the population just because that allele has a dominant effect on the phenotype. What additional factor would have to be present to cause a dominant allele to increase to a frequency of 100%? Why is this factor essential for the dominant allele to "take over" the gene pool?arrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning