Processes of Evolution - Population change due to natural selection

Question 1

What is stabilising selection?

Answer 1

Favours the most common phenotype as it’s best adapted. selecting against alleles that produce more extreme phenotypes

Question 2

directional selection

Answer 2

phenotypic distribution of a population shifts in one direction → favouring one extreme and establishing new phenotypic norm

Question 3

what is disruptive selection

Answer 3

Favours alleles that code for phenotypes at both extremes of a phenotypic range. can lead to speciation → driven by intraspecific competition

Question 4

What is a cline

Answer 4

A pattern of gradual variation between individuals over a geographical area → due to environmental differences therefore different selection pressures

Question 5

what is a deme

Answer 5

A subset population that has limited gene flow → isolated for a long time - new distinct subspecies or speicies