Isolation and speciation

What is genetic drift?

A change in the frequency of an allele within a population over time due to chance

Genetic drift is faster in what kind of populations?

Smaller population as the genetic diversity is less - the chances of new specifies developing is increased

What is speciation?

The evolution of new species from existing ones

What is adaptive radiation?

If populations become separated, the populations will become adapted to their different environments

How does sympatric speciation occur?

Reproductive separation of 2 populations can result in the accumulation of difference in their gene pools - no gene flow

Change in frequency of alleles

New species arise when these genetic differences lead to an inability of members of the populations to interbreed and produce fertile offspring

What is allopatric speciation?

Environmental change occurs causing two groups of the population to become physically separated - geographical isolation

Random genetic mutation

Differing selection pressures result in different alleles being favoured in the 2 environments

Populations become so genetically different they would be unable to interbreed

Geographical separation may be the result of what types of barriers?

Oceans, rivers, mountain ranges and deserts

What is sympatric speciation?

Speciation that occurs in the same habitat / environment / population