Question

What Causes Evolution?

Answer 1

Evolution:

1. Evolution is defined as the change in the frequency of alleles within a gene pool from one generation to the next.
2. As these characteristics are the expressions of genes that are passed from parent to offspring during reproduction

Causes of Evolution:

Mutations:

1. Mutations are the sources of genetic variability.
2. Mutations are rare but important
3. It is the random changes in the genetic material at the level of the DNA nucleotides or entire chromosomes.

Natural Selection:

1. It is the most important cause of evolution measured n terms of an organism's fitness.
2. It is genetically based differences in survival or reproduction that leads to genetic change in a population.
3. An example of a bottleneck.

Gene flow:

1. It is the movement of genes between populations.
2. In the plants, this can be accomplished by pollen or seed dispersal.
3. For example, plant pollen is being blown into a new area.

Genetic drift:

1. It is the random changes in frequency.
2. This is very important in a small population.

Sexual reproduction:

1. The combination of alleles forms new traits as a result of random mating.
2. Variations can also occur in sexually reproducing organisms as a result of crossing over gene recombinations during prophase 1 meiosis.
3. Variations can also be created as a result of the random orientation of chromosome's independent assortment during metaphase 1 of meiosis.