Why should humanity continue to exist?

"why should humanity continue to exist?" you question implies as if everyone supports that humanity should exist.

I personally believe humanity is a virus of planet earth.

I mean think about it, humanity expands and "destroy" the health of the earth. Every now and then the defense system of earth (earthquakes, thunders, etc) take place which kill some people but the virus is still strong. Not for ever though.

That's a good question we are the only species with the so called intelligence to truly enjoy the wonder and splendor yet instead of peace we create death war and destruction every where we go....humans make no sense we don't just bite the hand that feeds us we kill the whole thing instead

Because the very qualities that create the problems pointed out in some of the other answers are the qualities that give us the ability to transcend those problems.

It wouldn't, but evolution moulded all living creatures with a primal need to survive, else they would have died out. It isn't necessary for the Earth but, hell, I wanna live the rest of my life.

The universe takes its own direction, and we are part of it. Enjoy.