KA7- Speciation

Question 1

What is a species?

Answer 1

A group of genetically similar organisms capable of interbreeding and producing fertile offspring, and which don’t normally interbreed with other groups

Question 2

What is speciation?

Answer 2

The generation of new species by evolution

Question 3

What are species split by during allopatric speciation?

Answer 3

A geographical barrier, which prevents genes flow between the two new populations

Question 4

What are the 5 steps of allopatric speciation?

Answer 4

1) members of a large population share the same environment and interbreed

2) population becomes split which stops interbreeding and gene flow

3) mutations occur at random in separate populations but aren’t shared between them

4) natural selection affects each group - different conditions in each area favour different mutants

5) after a long period, the genes of the 2 populations become so different that they can’t interbreed to produce fertile offspring

Question 5

What is sympathetic speciation?

Answer 5

The two populations are genetically isolated by behavioural or ecological barriers