Peer review is essential to the scientific process because

Peer review is essential to the scientific process because of the need for correlation. In order for results or conclusions to be accepted and or more believable, your peers must come to the same conclusions as you. Your peers review your work and if there thoughts on the project align with yours, your work is more reliable.

Peer review process is important because sometimes it proves difficult for researchers and scientists to notice a mistake in the work they have done. chances are high that when the work is reviewed by the other scientists weaknesses can be easily identified and corrected. it also helps in release of unwarranted claims,  irrelevant findings, personal views, unacceptable interpretation and deliberate fraud. again, people have confidence with peer reviewed materials because they are sure they have been independently scrutinized by various researchers.      

If you remove all the lions from the savanna it will lead to a increase of gazelle and a increase of cheetahs becasue of no competition