 Most living beings reproduce. Humans make new human babies, monkeys make new monkey babies and dogs, well they make new dog babies or puppies. So basically reproduction is where organisms make new organisms which look very similar to them. Right? That's what reproduction is. But what I want to do in this video is think a little deeply about why is reproduction necessary. I mean think about it. Do you think reproduction is necessary to keep a living being alive? I don't think so. I don't need to reproduce to stay alive. This dog doesn't need to reproduce for it to stay alive. Right? I'm pretty sure you agree with this. So let me just write that down. It's important. So reproduction is not needed for individuals to stay alive. Right? Okay. And another important point is on top of that reproduction is it takes a lot of efforts. If you take humans itself for example, you might know, right? Like the mother has to carry the baby in her belly for nine months. And then even after the baby is born, both parents have to spend so much time and effort to bring up that baby. So clearly reproduction takes a lot of efforts and it's not needed for individuals to stay alive. Then why do we do it? That's the big question I want to try and think about. So can you pause the video at this moment and think a little bit about why do you think is reproduction necessary? Well, if you're given some thought, here's the answer. Or at least here's one of the answers. Although it is not necessary for individuals to stay alive, turns out reproduction is needed. Or it is necessary for the species, for the species to stay alive. Or we can say for the species to survive. Now the very first question you might have is, hey, what's a species? Let me just write that a little bit better. What exactly is a species? Well, for now we can just say species, think of species as we can say if organisms look similar and they have the ability to reproduce, then we will say they belong to the same species. For example, all humans look very similar in their body structure and everything. And we can reproduce so all humans belong to one species, all dogs belong to another species, all cats belong to another species. So if you want that species itself to stay alive, we will see reproduction is super important. And of course, if you want to learn more about species in great detail, we have a separate video called species. So you can always go back, go there and check that out. But anyways, let me try and clarify this with an example. Okay, so let's consider a group of deer, maybe in a forest. Now let's think about reproduction over here. Individually, each deer, they don't need to reproduce to stay alive. Reproduction doesn't help them to stay alive. Let's see what happens if these deers don't reproduce. What do you think will happen? Well, clearly as time passes by, the deers might get old and they will all die. Now, even if you forget the whole aging thing, even if these deers were immortal, meaning they could never age, just think about it. Even if they could never age, they can still die because there are so many predators around. For example, lions like to eat these deers, maybe. So lions hunt the deer, so that's one way that these deers can die. Another way could be natural calamities. Some deers might just get sick. So it's just a matter of time. All living beings, just a matter of time, eventually they will die. And so if these deers do not have the ability to reproduce, then they will be gone. And not only will it affect the deers because they're no longer deer, so that species is gone, but it will also affect these guys, right? And so you can see the whole ecosystem gets affected. Not only those species, but also the species that are dependent on them, the whole thing gets affected. And so, how does reproduction help? Well, let's see. If the deers are able to reproduce, then they can make more and more deers. So with reproduction, they have the ability to grow in number, to grow their population. And now, even if the deers keep dying, they keep getting hunted, and even if there are natural calamities in some part of the world, whatever it is, because of the sheer number, even if the few deers are dying, it's fine because the species can stay alive because they have the ability to just make more and more copies of themselves. So this is how a species can stay alive by reproducing. So again, let me just write that down. How does it ensure survival of species? Well, it allows the population to grow. That's important. It allows the population to grow, so the population grows. And because the reproduction gives them a chance to grow their population, they can counteract the population dying. They can counteract their organisms dying, and as a result, they can make their population stable. So this will lead to stability. Without this, the population, without the reproduction, the population will keep on reducing, and eventually it'll just become extinct. Now, guess what? There is another reason why reproduction is important. Super important. You know why? Because eventually we will see it's a reproduction that leads to evolution. Now, of course, evolution is a topic that we will explore in great detail in a separate chapter altogether. We'll talk about that in separate videos altogether. But just to give you an idea of how reproduction is linked to it, you might know that when individuals reproduce, the offspring, the children, they don't look exactly like their parents. For example, you and I don't look exactly like our parents, right? We'll talk more about why that happens in detail in future videos, but this is what we call variation in reproduction. The offsprings are not exactly similar to their parents. And as a result, what happens? Well, when these offsprings grow and they reproduce and make their children, again, there will be more differences, right? And so as more and more reproduction happens, there will be more and more differences. So every new generation will have more and more differences, more and more variations, we say. And eventually, if you now consider millions of years or millions and millions of generations, we will eventually see the difference that will be so huge that eventually we'll see new species altogether will arise. That's basically what we call as evolution, okay? It is a broad overview. And in fact, this is how we believe, you know, we, right now we have so many different species in our world because of evolution. Of course, we'll talk more about that in future videos. But you can now see what a big deal reproduction is for all living beings, right? All right. So just to summarize, what did we learn? We learned why reproduction is important. It's not needed for individuals, individual beings to stay alive. It's not an essential life process. However, it is needed for the species as a whole to stay alive. And how does it do that? Because reproduction allows the species to grow in number, to grow in population. Because of this, they can ensure that even if some of their organisms are dying due to various reasons, the population number won't reduce, the population will remain stable. And we saw just, we got just a glimpse of another reason why reproduction is important. Because as you reproduce, we find that the offsprings will have some changes. And then if you consider this over many, many generations, the changes accumulate. And that's how new species are born altogether. And that's how we believe that so many species that we have in the world today, we all came from this idea of evolution. And so without reproduction, evolution would be impossible.