Affiliate Marketing Secrets

Every animal has a niche in it’s environment right? So if an animal dies out then it’s role in the environment is not fulfilled. Thus leading to consequences. I ask this question because whenever I bring up spiders, I am told that they are vital in keeping the population of insects down. But how true is that statement. I mean if spiders were wiped off the earth, would it really come with disastrous consequences. Would it not simply lead to another insect that preys on the same thing to fill the gap. Would we really be head to toe in flys. I’m sure there are arachnid enthusiast who will tell me that spiders are sooooo important, but in reality, surely they are replaceable. Obviously it’s a hypothetical question, seeing as spiders would never die out.
Also, if every animal has an important role to play, what consequences came from the excitation of the Dodo. Did the Dodo have simply little or no role to begin with.