Question

What forces contribute to genetic evolution?

Answer 1

Evolution:

Evolution describes the different forces that act on populations to cause genetic change over time.

There are four forces of evolutionary changes:

1. Mutation
2. Natural Selection
3. Gene flow
4. Genetic drift

Mutation:

1. It is spontaneous changes in the DNA of gametes.
2. It generates random genetic variability
3. Mutations in gametes are heritable.
4. It can have advantageous, deleterious, or neutral phenotypic effects.
5. The original population has new allele frequencies.
6. Prerequisite to all other evolution.
   

Natural Selection:

1. It includes the genetically based differences in survival or reproduction that leads to genetic change in a population.
2. It is based on the selection and propagation of the traits that are responsible for adapting to the constantly changing environment.

Gene flow:

1. It is the movement of genes between populations.
2. In plants, it can be accomplished by pollen or seed dispersal.

Generic drift:

1. It is the random changes in gene frequency.
2. This is very important in small populations.
3. It reduces genetic variability.
4. Examples: Bottleneck effect and founder effect