Haven't you been questioned about the issue that why we save the endangered species? Sure, it will be sad if there are not any pandas on the planet, but its not like we depend on them. And of course, there are quite a number of ugly species like insects and predators like tigers. However we do protect them as well.

On the face of it, there are plenty of reasons why we shouldn't bother to save endangered species. The most obvious is the staggering cost involved. Why should we spend all the money on wild life when we could spend it to stop people from dying of starvation or disease?

Another question we always brings it up is the distinction of dinosaurs, because if extinction is a natural process that goes on even in the absence of humans, why should we stop it? Maybe the third period of widespread extinction is on the process and we can not actually save them after all.

But beyond that, there is a simple reason to save species: because we want to. Nature is beautiful, and that aesthetics value is a reason to keep it, just as we preserve artistic masterpieces like the Mona Lisa. This argument is not so convincing as we take the tiger for example. For many villagers, they are a threat to both human and their sheep, even though some wealthy people think they are beautiful and are eager to spend their own money on saving them. However, the action of saving endangered animals is a social issue, we need a reason that are persuasive enough for the society as a whole, right?

There must be a more practical reason to keep species around. The practice of exploring nature to find commercially useful products is called bioprospecting. It does, sometimes, lead to useful new things, but it comes with a host of problems. And as we can see, most of the medicine we can synthesize by our own and thus we do not depend on certain species. Plus,  the local people know that some of the species in their region has medicine value and legal battles have been fought over this. So this argument, while it has some force, doesn't get us very far. 

We have another benefit that finally found itself kind of convincing, which most of us take for granted, is called "ecosystem services". The most obvious example is the bees can transfer pollen and is useful to the fruit and vegetables we grow. These are quite direct, but sometimes the services provided can be more subtle. But from the utility point of view, the ecosystem have nothing to do with me because I just sit in my office all day.

The point is that, while we could in theory do all these things artificially, it would be very difficult. It is far easier to let the existing wildlife do them for us. We took the argument a step further by asking how much we would gain by conserving biodiversity. In other words, conserving nature is a staggering good investment. 

In fact, one of the good things about the idea of ecosystem services is that it is all-encompassing. As a result, the weaker arguments we mentioned before now start to make some sense. The pure natural beauty can even moved the most cold-blooded person. You may well ask how we can put a price on that. How do you objectively measure beauty? Well, you can't, but that doesn't stop as deciding what it is worth. We do it all the time with paintings, potteries and other forms of art. If we value something and we are prepared to pay to have it, then it has value. To the same thing with nature, we just need a system that allows us to pay to experience it. In principle, ecotourism offers a way to make the beauty of nature pay for itself. 

I believe most of us have heard the word bio-network. In order to protect a certain kind of animal, we need to protect their meal, plants or animals, and they are part of a wider network of species, and it is difficult to separate them from it. Wiping out one of these species might not make much difference, but then again it might cause a chain reaction that alters the entire ecosystem. It is hard to predict the effect of killing off a species unless you go ahead and kill it-and then it is too late to reserve it. 

So for own own good-both in terms of practical things like food and water, and less physical needs like beauty-we should protect them.  Human society is a part of the ecosystem,too. In specific situations we might choose to favor one or the other, but overall we have to do both. It is not only for some solo intents to save the endangered species, instead, it is about seeing human society and wild ecosystems as one inseparable whole.