9D Speciation

Question 1

Steps of Allopatric Speciation

Answer 1

1. Geographical Barrier - State the geographical barrier that has isolated A populations or A species, thereby preventing gene flow
2. Environment - The isolated populations are subjected to different selection pressures which cause favouring phenotypes allowing the accumulation of genetic differences
3. Speciation - Once the sufficient genetic differences accumulate, the isolated populations will no longer be able to produce fertile offspring then two species have formed

Question 2

Sympatric Speciation

Answer 2

Involves the formation of a species in populations locate in the same geographical location
Sympatric speciation can also arise from genetic abnormalities that occure in gamete formation
It is thought that ancestral species was divided by distruptive selection eg. bimodal distrubtuiono fthe population due to natural selection.

Question 3

Galapogous Finches

Answer 3

• Allopatric speciation
• Radiated speciation

Question 4

Lord Howe Palms

Answer 4

• Sympatric Speciation
• Genetic abnormalities that allow behavioural differencs that accumulat and cause gentic differncs which allows two species to diverge