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Welcome to ANI in the air, wondrous Wednesday.
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This is where I talk about something wondrous.
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Last we left, back in December,
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November, December, I'm not sure which, I was
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talking about evolution, thought I'd pick that up again. So,
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we had the origin of life from
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4 billion years ago or so, and then life kind of
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just went along. There was some interesting advances.
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I think perhaps the biggest one was the
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mitochondria joining with the cells.
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You know, kind of two different organisms joining together
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as one, and that's what all of our cells
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do now. But, there was another
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very significant event in evolution, which was
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the joining of two individuals of the same species to create a third.
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That event
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unlocked very rapid evolution.
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Before then, it was, I believe,
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pretty much just single-celled organisms. Happened about
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a billion years ago or so, I believe, and
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you know, after that point, animals,
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plants, fungi, they all
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evolved, and the question is sort of
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what was so powerful about it? Well, there was a couple of
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competing influences as I understand it.
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Namely, you know, each individual
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would contribute one of each chromosome.
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You know, the DNA stuff that has the genes in it.
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And, by having a second individual
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do that, things that were
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damaged could be dealt with in a more stable
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fashion and prepared. So, that's one wonderful
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bit of that. But, another bit was changing it up.
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So, basically, let's just
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take humans. Humans have 23 chromosomal pairs
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and each pairing from one of the parents
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you know, there's, each parent
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has two, so you can choose one out of two of those.
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So, for each sort of chromosome pair, there's basically four choices
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that can happen. And then, from that, you have
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23 pairs and so you have 4 to the 23rd possible different
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chromosomal arrangements. Now,
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not everything on the chromosomes are different from each other, but
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it's, you know, sufficiently
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enough difference that variation can happen from all that.
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Just how big is 4 to the 23rd? Well,
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4 to the 23rd means you have 23 4's being multiplied together.
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Instead of 4's, you could go to the 2's and 2's becomes 2 to the 46.
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So, how many 2's you got? Now, 2 to the 10th is
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1024, or about 1000. So,
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2 to the 46 is, you've got
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1000's
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basically being multiplied there, or 1000 to 3 10's, so
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12 10's. And then you have 2 to the 6th left over
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and that's 64. So, round that up, you got 7
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times 10 to the 13th. So,
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70 trillion different unique
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individuals possible from 2 people producing a
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3rd. That's pretty fantastic. 70 trillion.
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That's a lot. That's just
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one couple. Then you have that across from
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billions of people and you have a lot
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of variation and differences going on. Now, to what extent
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the genes and the chromosomes are different and producing
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differences, I don't really know. Obviously,
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all of our basic structures need to be replicated, but there's always
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lots of variations and I imagine that the ones
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that are most susceptible
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to interesting variations are the most
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varied in our population. And the others kind of get honed down.
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And when that happens, I have no idea. I also have no idea how
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different number of chromosomal pairs evolve over time.
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I can only imagine that there's some sort of
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merging and breaking of chromosomes that can happen. Discarding,
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I don't know. But it's hard to
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understand how that actually happens with different
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individuals coming together. If somebody's got a different number of pairs, I feel like
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they're problematic. So I don't know. That's something I wonder about.
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But basically, that combinatorial
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power is what's responsible for
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the rapid adaptation
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that we see in life.
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From a billion years ago, we went from just single-celled
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organisms to
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all, almost everything we see. Grass, trees,
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people, squirrels. I'm just talking about what I'm
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actually literally seeing right now.
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I don't actually see any birds. The birds.
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Anyway. So, yeah.
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That's just fantastic variability.
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And before
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this introduction of this concept of two individuals producing a third
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happened, the way
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change happened was random mutations in the copying
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mechanism when a cell would just
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get enough stuff going on that it would want to split into two.
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So it would make a copy of itself and there would be errors in that process.
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There could also be other damages even in existing cells.
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And so, you know,
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that kind of random change is not very
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effective most of the time. It's probably a bad thing that happened and very rarely
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would something good happen from it.
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Of course, we're talking billions of years, so rare is still
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quite likely to happen. But it certainly
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takes much longer. When you have
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this chromosomal pairing going on, you can have all that variation
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working in something that actually does work.
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You know, these two individuals, they've got chromosomes that
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are working and they're pairing up in different ways. And so
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when you combine them in new stuff,
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that mixing kind of
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can generate something new and interesting. And if that's
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more well adapted to the environment around, then that
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individual is more successful and, you know, passes it along
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and if it becomes more and more
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successful, becomes more and more in the population, then
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pretty soon the population has those new stuff
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filtering in. So, I mean, there still
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must be some source of changes and mutations, but
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it's
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quite fascinating. 70 trillion.
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That's how many different people, two people can produce.
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Isn't that amazing? That's amazing. Anyway, that might have been more of a Millions
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Monday thing, but I enjoyed it. So, power of
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evolution, power of two people coming together to produce a third
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is, you know, amazing.
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Alright, thanks for listening and
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see you when I see you.