Natural selection vs artificial selection: life sciences grade 12 | ThunderEDUC | M.SAIDI

Welcome back to our class, don't forget to subscribe if it is your first time to visit our channel. Let's look at artificial selection. What is because we have talked about natural selection, nature selects which one is best suited to the environment, but here artificial selection is the human which selects which one is supposed to continue with life or not. Which characters do you need, actually it depends on, it depends on the desire of the human being. It is where humans select for a desirable characteristic or select for desirable traits in agricultural products, animals rather than leaving the species to evolve naturally or gradually without human interference. So in this case, we have humans are being interfering, what is happening in the what in the environment. So humans select, maybe I want birds with or chicken with big, big eggs, which can produce big eggs. So I'll be selecting them for for a long time. Humans have been using this kind of method during breeding experiment to develop organisms with a selected set of desirable characteristics. So they keep on selecting those which are having desirable characteristics, then they select them, and then they keep them. And those which don't have desirable characteristics, they move them from the what from the system. An example, you can find that they do select because of the following reasons. Number one, increase the quality and quantity of milk produced by cows. Sometimes you can ask you the functions of artificial selection, the benefits of artificial selection. So these are the things you can give us that results in increase the quality and quantity of milk production or produced by the cows. Then also drought resistant organisms, they select for those organisms which can resist the droughts. And then disease resistant organisms also select they want organisms which can resist diseases. Yes. So these are benefits also of artificial selection. And then increase sugar content in the sugarcane, because they want to produce a small sugarcane can produce a large amount of sugar. So these are some of the examples they studied with these dogs, you find out that they want these characteristics. So these dogs which have such characteristics, they are being kept, they are being bred so that after so many generations, you end up having such the same story here, they started with this, you see 1957, the chicken was like this 1978, 2005, it's like this. So it means that the one which can have big meat or can produce meat, then they are being what? Selected for. And then those ones which can produce big meat or large meat or high quality meat, then they remove them from the system. The same story here to the maize and wheat. So this is the process what happens. Suppose you want to, you want, you wanted a variety of cow that can produce a lot of milk. So what happens? You choose or select the cow in your herd that produce most milk. So you look, you are looking for the cow which has the characteristic you are looking for or a character you're looking for. And then you let these cows reproduce, you let them mate and then they reproduce. Then they will produce kids. They select the offsprings that produce the most milk. So the offspring will be produced and these offsprings will be having those which can produce more milk and those which can only produce more milk. So those which can produce more milk, you keep them. So you keep on selecting them until the genes become pure. Then you're saying that you let only these offsprings reproduce. The one which can produce milk, you let them reproduce. Keep repeating the process of selection and breeding until you achieve your goal, until those animals which can produce milk are obtained. So what are some of the differences between natural selection and artificial selection? So we have seen that in natural selection, environment, yes, it occurs in the environment. So the environment or nature is the selective force, while in artificial selection, humans is the selective force. Here in the environment, the environment selects which one is the best suit, while this one is human, like desirable characteristics. Then number two, selection is in response to what suits to the environment, which character can survive in the environment, while here it satisfies the human needs. It's not about which character is suitable in environment, no, what sustains the human needs. Then this one occurs within the species, while this one is occur, it can occur in one species more than one, yes, because you can crossbreed from different, between the two species, yes. But while this one occurs in one species, strictly in one species, yes. So that's some of the differences between artificial selection and natural selection. Let's look at aspeciation.