Biston betularia (peppered moth)

Decline of the light-colored phenotype from 1848-1898

Use the slider to set the selection coefficient s in Haldaneā€™s model, which assumes that the light-colored (non-melanic) form is selected against with selection coefficient s.

Can you find the value of s that reduces the light-colored phenotype from 0.99 down to 0.01 over the 50 year period 1948-1898? Haldane (1924, p. 26) found the value to be approximately 0.3.


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