00:01
First up on our evolutionary mechanisms is natural selection.
00:14
Under the pressure of natural selection, organisms and their genotypes are naturally going to vary in the reproductive success, or their ability to survive and reproduce.
00:41
This, of course, is going to structure the frequency of their alleles as well.
00:55
To see how this might happen, let's take a look at a hypothetical population.
00:59
We have three genotypes, and let's say they're initially all having the same frequency.
01:17
These three are our different elites.
01:18
Now, say something happens to this population, in which our topolial becomes much better at survival and reproduction.
01:33
Throughout the succeeding generations, we are going to see that one become a lot more common at the expense of the other ones.
01:48
This is natural selection.
01:51
Some genotypes gain a reproductive advantage, and so become successively more common as time goes on.
01:59
Next up in our mechanisms, we have mutation.
02:10
Mutation as it corresponds to evolution is when changes in dna, as the copying of dna from generation to generation is never quite so perfect.
02:27
So the changes in dna are going to result in altogether new genotypes.
02:43
It might look something like this.
02:44
Say we have our same three alleles, but maybe over time, our top one, again, undergoes a chance mutation to split its genotype into two.
03:02
Now in this population, we have.
03:08
We have a new genotype and allele enter the fray.
03:15
Next up, we have genetic drift.
03:28
In the process of genetic drift, a random chance removal of genotypes restructures the population.
04:08
Let's take a look at what this might look like...
