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Note that your final mark will not be saved in the system.
Note that your final mark will not be saved in the system.
Evolution and speciation Categorise
Target Level
C
Running Total
0
0%
Attempt
1 of 2
Click on an item, then click on a category to place it. Or, drag and drop the item into the correct category. Organise all items before clicking 'Check'.
Stabilising selection
Directional selection
Disruptive selection
Occurs when environments change
Favours phenotypes that vary in one direction from the average, and selects against phenotypes that vary in the other direction from the average
Example: colouring of animals in an area with light and dark backgrounds
Favours extreme phenotypes
Selects against extreme phenotypes
Favours the current average phenotype
Occurs in environments where conditions are fairly constant
Occurs when an environmental condition can take more than one distinct form
Example: mass of human baby at birth
Example: antibiotic resistance in bacteria
Selects against the average phenotype