Is there anyone who don't believe in supernatural creator,god?

i don't. i used to believe few years before. but after deep thinking that if god exist why he/she made sharks, tiger who just kill others, if he/she is so powerful why can't god maintain the natural cycle. why there are people doing things to small children, why killing each other by saying their religion is grater than others, why cant god kill them before they do those dirtiest work of which we even don't like to speak. if god do exist then he/she is not doing its job properly . that's just my opinion . i never say others to not to believe in. now tell me why , for what you believe in god.