...--mutation.¹

Well, that's not quite true. We talked about multiple populations when we talked about the Wahlund effect and Wright's $F_{ST}$, but we didn't talk explicitly about any of the evolutionary processes associated with multiple populations.

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... mutation.²

Technically what the population reaches is not an equilibrium. It reaches a stationary distribution. At any point in time there is some probability that the population is in a particular state. After long enough, that probability stops changing. That's when the population is at its stationary distribution. We often say that it's ``reached stationarity.'' This is an example of a place where the inbreeding analogy breaks down a little.

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... ones.³

Remember that if we're dealing with a non-ideal population, as we always are, you'll need to substitute $N_e$ for $N$ in this equation and others like it. Similarly, if you're working with a haploid organism, $f$ will increase as $1/N$ per generation, so the formula will be $\hat f = 1/(2n\mu + 1)$. In other words, everywhere you see a $4N$ in the formulas I present here, you can substitute $2N$ and get the result for a haploid population.

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....⁴

We don't have to make this assumption, but relaxing it makes an already fairly complicated scenario even more complicated. If you're really interested, ask me about it.

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....⁵

See the ``few more details'' section that follows if you'd like to see for yourself how similar they are.

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... alleles.⁶

Sounds a lot like the infinite alleles model of mutation, doesn't it? Just you wait. The parallel gets even more striking.

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... models.⁷

I warned you weeks ago that population geneticists tend to think backwards.

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... another.⁸

You read that right it's $2Nm$ not $4Nm$ as you might have expected from the mutation model. If you're really interested why there's a difference, I can show you. But the explanation isn't simple.

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... another.⁹

In the sense that the stationary distribution of allele frequencies is hump-shaped.

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... diverging.¹⁰

And one immigrant every other generation corresponds to a backwards migration rate of only $5\times 10^{-7}$.

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... diverging.¹¹

And one immigrant every other generation corresponds to a backwards migration rate of $5 \times 10^{-2}$.

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