Speciation, Cloning.

Speciation.

Development of a new species occurs when populations of the same species become reproductively isolated.

Geographical Isolation and Natural Selection.

A physical barrier divides a population.

Conditions can vary either side of the barrier. Different characteristics then become more common due to natural selection.

Reproductive Isolation.

The two species can no longer reproduce. This can be due to:

* Seasonal changes.

* Mechanical changes.

* Behavioural changes.

Phylogenic species concept is used to classify. It uses common ancestors.

Cloning.

Reproductive Cloning.

Creates another organism genetically identical to another organism.

Used in testing or reliability, genetic variables are removed.

Also used to save endangered animals from extinction.

Non-Reproductive Cloning. (Therapeutic Cloning).

Makes embryotic stem cells that are genetically identical

Harvested from young embryos, used to replace damaged tissue.

Both carried out using Nuclear Transfer.

*A body cell is…