... that¹

Remember, I told you that ``it can be shown that'' hides a lot of work.

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...$A_1$²

The beneficial allele.

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....³

Unless $p=1$.

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... time.⁴

The exact calculation from equation (1) gives 82% for this probability.

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... selection⁵

i.e., the magnitude of differences in relative viabilities

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... fixed.⁶

Because the larger the population, the smaller the effect of drift.

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...table:fixation).⁷

Because it's probabliity of fixation is equal to its current frequency, i.e., $1/2N$. We'll return to this observation in a few weeks when we talk about the neutral theory of molecular evolution.

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... loss.⁸

In some cases it can actually accelerate its loss, but we won't discuss that unless you are really interested.

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... small,⁹

As with mutation and migration, what counts as large or small is determined by the product of $N_e$ and $s$. If it's bigger than one the population is regarded as large, because selective forces predominate. If it's smaller than one, it's regarded as small, because drift predominates.

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