Life in all of its aspects is complicated, far more complicated and intricate than most people could possibly imagine. It is fantastic that man sees something such as the flight of birds and believes deep within his psyche, that he too should be able to fly, or that man sees the fish of the sea, and believes deep within his psyche, that he too should be able to swim in water. So too, in looking at the human body, man believes that it can be improved upon or modified, or re-configured, which perhaps is true to a point. The thing about the body, is when you hear from esteemed medical doctors or pundits that you don't necessarily have to have two kidneys, or that they don't really know the reason for having an appendix, or that your tonsils aren't really necessary if you are, for instant, constantly suffering from strep throat or similar, is that your body is far more complicated, far more intricate, than perhaps even medical doctors are really aware of.
So too, when looking at nature itself, people wonder that since mosquitoes are the reason for yellow fever as well as other air-borne transmitted diseases, as well as there being other insects or animals, that seem to be rather detrimental in some respects to humans, and with humans having to be on constant guard against dangerous bacteria, viruses, and parasites, one conclusion that might be reached is that we must therefore need to live in a world which is completely antiseptic, but that isn't necessarily the truth, because, again, it is far more complicated and intricate than that.
For instance, there is a lot that people can learn from the process of immunization, in which, the principle of such is for the body to be injected with a known agent accomplished though without its associated pathogen, this thus creates still an induced immune response from the body, and hence immunization against this particular pathogen, thereby, providing protection to the body from that pathogen without having to destroy the pathogen itself. This is a prime example of understanding nature, and rather than taking a path of the wholesale destruction of the pathogen in nature which may or may not cause problems, known or unknown in the future, instead, the body is trained to defend itself from such.
It's wonderful, that man sees the world and wishes to improve upon it, and desires to re-make the world in all of its many aspects bend to his will, but hubris on the part of mankind can in itself set in motion tragedies that need not occur. This is why things that are built in order to make life safer or more efficient may instead end up making life more dangerous and ultimately are found not to be efficient. It is the reason too that the unthinking application of chemicals, or antibiotics, or myriad other things, may indeed have unintended consequences.
There is a beautiful symmetry in nature that first should be observed, than should be understood in all of its many aspects, before mankind takes the step of improving or affecting his will against it. It is the easiest thing in the world to state that one knows what one is doing, and thereby to trust that judgment, but in reality things, more often than not, are far more complicated, and those that will not take the time and consideration to learn at the feet of nature, will find directly or indirectly that this insensitivity is akin to fire, which though it illuminates, also burns.