Speciation gap fill

Gap-fill exercise

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The evolution of new species from existing ones is called . A species is defined as a group of individuals that can to produce offspring.

1) A population becomes from other populations. This can be geographical separation (called speciation) or reproductive separation (called speciation).

2) can occur to make the populations genetically different.

3) The populations will experience different pressures due to differences in their .

4) selection will lead to changes in the frequencies of the populations.

5) Eventually the genetic differences will be large enough that even if the populations were no longer , they would not be able to with each other.

Small populations are more likely to develop into a new species due to genetic . There will be a smaller variety of in a small population (lower diversity). Alleles that are selectively favoured and passed on will more quickly affect the whole as their frequency will be .