Equation 4 · Part 1 · Darwin's Finches: The Beak the Grants Measured for Forty Years
Symbol R
What this part means
the response: the amount the population’s mean should shift in the next generation, if the difference between survivors and non-survivors was genetic rather than purely environmental.
Its job in the formula
R is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol R→Article meaning
Where the article explains it
where S is the selection differential actually measured on the population in one generation, is the trait’s heritability, and R is the response: the amount the population’s mean should shift in the next generation, if the difference between survivors and non-survivors was genetic rather than purely environmental.
The passage around this formula
where S is the selection differential actually measured on the population in one generation, is the trait’s heritability, and R is the response: the amount the population’s mean should shift in the next generation, if the difference between survivors and non-survivors was genetic rather than purely environmental. Grant and Grant ran exactly this check on their own data, comparing the mean of a trait before a selection…
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Sources cited in the surrounding passage
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