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Equation 7 · Part 1 · Human Evolution Did Not Stop, and Medicine Is Now Steering It

Symbol f

ff
ff

What this part means

f is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

f is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

…happen to pair up. Layered on top of that structural limit is the fact that PGT operates only within IVF, itself a minority pathway to conception worldwide, so the realized value of the effective screening fraction f across all human conception is far below the illustrative s=1 ceiling used above. Screening’s population-genetic footprint, in other words, is real, directionally opposite to the tiny drift toward higher mutation load discussed earlier, and — on the arithmetic above — slower than either.

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A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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