- ....1
- I hope that's beginning to sound
familiar by now.
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- ... generation.2
- An important assumption of the
coalescent is that populations are large enough that we can ignore
the possibility that there is more than one coalescent event in a
single generation. We also only allow coalescence between a pair of
alleles, not three or more. In both ways the mathematical model of
the process differs from the diagram in
Figure 1.
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- ... is,3
- How many times
have you seen this now? The only complication is that I'm specifying
that we're interested in the inbreeding effective size.
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- ... that.4
- Remember that we're counting generations
backward in time, so when I say that a coalescent event occurred at
time
I mean that it occurred
generations ago.
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- ....5
- If
you've had a little bit of probability theory, you'll notice that
equation 1 shows that the coalescence time is a
geometric random variable.
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- ...
alleles.6
- Okay, okay. What I should really have said is ``It's
not too hard to extend this approach to multiple alleles.`q''
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- ... follows7
- Using logic just like what we used in
the two allele case.
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- ... is8
- If you don't see why, don't worry about it. You
can ask if you really care. We only care about
for what
follows anyway.
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- ... progress.9
- Well, we can't make any more
progress using
-statistics. We'll see in the last week or two of
the course that it is possible to make some progress on
disentangling the relative role of migration and common ancestry by
using more of the information available in molecular data.
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