Question

In stabalizing selection :

1. How is the relative fitness of genotypes affected when selection is acting against homozygotes?

2. What effect does it have on the mean phenotype and genotypic/phenotypic variation within a population?

In disruptive selection

1. How is the relative fitness of genotypes affected when selection is acting against heterozygotes?

2. What effect does it have on the mean phenotype and genotypic/phenotypic variation within a population?

1. How does selection typically affect genotypic/phenotypic variation between populations?

How do mutation rate and/or selection coefficients affect the equilibrium frequency of deleterious alleles?

Answer 1

1. In stabilizing electun, inslead a favouning individuals with exheme phenotypes, if favours the intermediate variants. Stabilizing selection Tends to remove the more covere phenotypes, resulning in the reproductive success of the norm o Ave Acide phonotipis. This means that most common phenotype in the population is selected for and continue to carinate in future generations. Because most traits change little over time, stabilizing Selection is thought to be the most common type of selechon im most population 2. Stabilizing selection cause the narrowing of the phenotypes seen in a population. This is because the extreme phenotypes are selected against, causing reduced survival on organisms with those traits .

This results in a populahon consisting of fewer phenotype with most traits representing the mean value of the population. This narrowing of phenotype causes a reduction in genetic diversity in a population. . It is a mode of natural selection in which extreme values for a trait are favoured over intermediate values. This type of selechon often drives specialion. I The makeup of this type of population would show phenolypes of bolh extremes but have a very few individual in middle Disruptive selection happens in large populahon will lots pressure for the individuals to find advantage or niches as they compete with each other for food bo survive and parmers to pass :

on their lineage Two or more divergent phenotype in an environment may be favoured simultaneously by diversifying selection. No natural environment is Hemorygous homogeneous; rather the environment 1, any plant or animal populahon is a mosaic consisting of more or less dissimilar subenvironments : There is heterogeneily will respect to climate food resources & living space . 2. in disruphive Selection, species cope with environmental heterogeneity in divere ways. One strategy is genetic monomorphism, the selechion ch a generalist genotype that is well adapted to all the subenvironments encountered by me species.