Micro-evolution
Micro-evolution is the change of the gene pool within one species over time. This change occurs because of mutation,natural selection, gene flow, genetic drift and non-random mating.
The gene pool changes through variations resulting from those 5 points. An example is the British peppermoth which changed it color from white to black because the white trees darkened during the Industrial revolution. Therefore they changed (directional selection) from a white population to a dark population.
The gene pool changes through variations resulting from those 5 points. An example is the British peppermoth which changed it color from white to black because the white trees darkened during the Industrial revolution. Therefore they changed (directional selection) from a white population to a dark population.
Gene Pool
The Gene Pool is the mixture of all available genes ( DNA ) in one population that is available for the next generation. It therefore contains all varieties and versions of genes.
The Gene Pool is the mixture of all available genes ( DNA ) in one population that is available for the next generation. It therefore contains all varieties and versions of genes.
1. Mutation
Mutation is a random change of DNA of an organism that causes variations. If one of those variations is 'survivable', it can be passed on to future generations and therefore change the gene pool.
Mutations can have 3 outcomes: good, bad or neutral. Many mutations don't effect the amino acid sequence and therefore have no effect on the species.
Mutation is a random change of DNA of an organism that causes variations. If one of those variations is 'survivable', it can be passed on to future generations and therefore change the gene pool.
Mutations can have 3 outcomes: good, bad or neutral. Many mutations don't effect the amino acid sequence and therefore have no effect on the species.
2. Natural Selection
The organism that is most fit to the environment survives and passes on it's gene (mainly this specific variation is represented in the gene pool).
3. Gene Flow
Genes fro one population transfers over to another and causes an introduction of new variations. Conversely, if the gene flow stops, populations change independently although once one.
Genes fro one population transfers over to another and causes an introduction of new variations. Conversely, if the gene flow stops, populations change independently although once one.
4. Genetic Drift
The gene pool changes in a population by chance and because of random events (i.e.: one variation passes on more genes that the other by chance and is therefore more present in the gene pool).
The gene pool changes in a population by chance and because of random events (i.e.: one variation passes on more genes that the other by chance and is therefore more present in the gene pool).
5. Non-random mating
Animals barely ever mate randomly or by chance. They mate to pass on their genes in the most successful way.
For example:
Harem: one male has many females
Assortative mating: choosing those like you
Sexual Selection: selecting after criteria like color, displays, territory, song, size,...
Animals barely ever mate randomly or by chance. They mate to pass on their genes in the most successful way.
For example:
Harem: one male has many females
Assortative mating: choosing those like you
Sexual Selection: selecting after criteria like color, displays, territory, song, size,...