8. Genetic Drift and Speciation

Question 1

define speciation?

Answer 1

the evolution of a new species from existing old ones

Question 2

what is allopatric speciation

Answer 2

when populations are geographically isolated, leading to speciation

Question 3

define sympatric speciation

Answer 3

occurs when populations are reproductively isolated within the same environment

Question 4

outline allotropic speciation

Answer 4

• geographical speciation occurs
• gene pools are separated
• mutations will occur, introducing genetic variation
• the most suited alleles will be passed to offspring, which will further decrease allele frequency

Question 5

outline sympatric speciation

Answer 5

• formation of a new species from a population
• random mutation/ change in behaviour prevents organisms breeding with each other
• no interbreeding can occur
• this leads to changes in allele frequencies into the new different populations

Question 6

name the mechanisms of reproductive isolation

Answer 6

• temporal changes (i.e. season, and flowering seasons)
• mechanical changes
• behavioural changes