Genetic variation, diversity. ( :

All members of the same species have the same genes. Organisms differ in their alleles. It's the combination of alleles that the organism has that makes indivaiduals within a speicies, different from one and other. The greater the number of alleles all the memebers of that species have, the greater the genetic diversity.

Factors that influemce genetic diversity:

• Selective breeding
• The founder effect
• Genetic bottlenecks

Selective Breeding - Deliberatley picking out offspring with desired characteristics, and using them to parents the next generation so that these alleles are more likely to be passed forward. Members of the species without these characteristics are made unable to continue breeding so that only the desired characteristics are carried forward.

Genetic diversity: Caused in differences in alleles.

Genotype: The alleles you have for a particular gene.

Factors that reduce genetic diversity: Selective Breeding, The founder effect, genetic bottlenecks.

Factors that increase genetic diversity: Mutations, different alleles being introduced by migration.

Selective breeding, unwanted alleles bred out of population. Reduced genetic variation.

The founder effect: Part of the population colonises elsewhere, only certain alleles go, therefore, genetic diversity decreases, due to the changed frequency of alleles.
Can eventually create completely different species.

Genetic bottlenecks: Something reduces the population to a really small number. Some alleles, are, therefore not carried on. This means that some trait s are lost, and genetic diversity is lost.

Variation: continuous, discontinuous. In continuous, it is controlled by multiple genes, affected by the environment, and there are a large range of phenotypes. With discontinuous, it is controlled by a single gene, it is less affected by the environment, and there is a small range of phenotypes.