Loss of their original diversity per generation

=1/2n

Gain of their original diversity per generation

=1/2n 

Gain or Loss of their original diversity per generation

=1/4n

TLS Online TPP Program

#Id: 9197

#Section 3: Genetics, Cellular and Molecular Biology

Stabilized natural selection

Favor intermediate phenotype but eliminate lower and higher-grade phenotype

It introduced homogeneity in the population

Exp - clutch size of birds that lay too many or too few eggs per nest have lower fitness values than do those that lay an intermediate number of eggs

TLS Online TPP Program

#Id: 9198

#Section 3: Genetics, Cellular and Molecular Biology

TLS Online TPP Program

#Id: 9199

#Section 3: Genetics, Cellular and Molecular Biology

Directional Natural selection

Directional selection favors individuals at one extreme of a phenotypic distribution that have greater reproductive success in a particular environment.

TLS Online TPP Program

#Id: 9200

#Section 3: Genetics, Cellular and Molecular Biology

1. Resistant to pesticide in insect

2. Antibiotic resistant in pathogen

3. Industrial melanism

TLS Online TPP Program

#Id: 9201

#Section 3: Genetics, Cellular and Molecular Biology

TLS Online TPP Program

#Id: 9202

#Section 3: Genetics, Cellular and Molecular Biology

Disruptive Natural selection

Disruptive selection favors the survival of individuals at both extremes of a range, rather than the  intermediate.

Increase variance in the population because select those phenotype which are away from mean.

It maintain balance polymorphism and maximum selection coefficient value.