The “default fate” of the ectoderm is to become neural tissue

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#Id: 9199

#Unit 11. Evolution and Behavior

Directional Natural selection

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

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#Id: 9200

#Unit 11. Evolution and Behavior

1. Resistant to pesticide in insect

2. Antibiotic resistant in pathogen

3. Industrial melanism

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#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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#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