So because there are 7B people, the value of a single life is reduced? This is all wonderful until that one person happens to be someone close to you. You think like Stalin & Mao. Who gives a fuck if we kill off a few million people? We'll have plenty left.
Your argument invariably leads to a solipsism and a skewed view of the world.
You are choosing to destroy a whole species of animal who we share OVER 95% of our DNA with out of some kind of species-centric "survival of the fittest" theory. We - the human race - have been on this planet a mere 100-250 thousand years (jury is still out on exact numbers) and, along with every other animal living on this little rock, have been quite lucky to still be around considering 99.8 or so % of the animals EVER living on this planet have become extinct. There is a reason we and other animals have survived nature's culling. To suddenly deem our species more important than all others is folly and utterly foolish. I can assure you - and so will the great majority of biologists and paleontologists - we're here at the grace of other arguably more important species. Take a bee for instance - they don't need us for their existence but we'd have a VERY hard time existing without them. Again - my views don't come from some kind of PETA, Greenpeace, "liberal" blind love of all "beings"- it comes from common sense and a sense for the FUTURE of our little species.