Broad-sense heritability range from 0 to 1.

0 =all of the phenotypic variance results from environmental variation.

1 =all of the phenotypic variance results from differences in genotype.

TLS Online TPP Program

#Id: 9201

#Unit 11. Evolution and Behavior

TLS Online TPP Program

#Id: 9202

#Unit 11. Evolution and Behavior

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.

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#Id: 9203

#Unit 11. Evolution and Behavior

Balance natural selection

Balancing selection is a type of natural selection that maintains genetic diversity in a population.

In balancing selection, two or more alleles are kept in balance, and therefore are  maintained in a population over the course of many generations.

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#Id: 9204

#Unit 11. Evolution and Behavior

Evolution by natural selection occurs if variation must lead by Ecotypes. 

Ecophene is not be selected by natural selection

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#Id: 9205

#Unit 11. Evolution and Behavior

Change in environmental condition is not necessary for natural selection.

TLS Online TPP Program

#Id: 9206

#Unit 11. Evolution and Behavior

Genetic drift 

Genetic drift is an evolutionary force, in which allelic frequency change over generation Just by chance (sampling error). 

The deviations from the expected ratios are random, the direction of change is unpredictable.